Complement cascade (Homo sapiens)

From WikiPathways

Revision as of 12:11, 16 July 2014 by ReactomeTeam (Talk | contribs)
Jump to: navigation, search
6, 29, 46, 62, 8152, 84261, 71, 72, 86463, 7, 28, 508013, 24, 47, 51, 59...4, 8, 15, 17, 32...528654, 6944, 687416, 25, 38101427, 663012, 56, 654641, 7810, 23, 3375461, 21, 452, 5319523566, 67, 85643535, 6960184, 11, 13, 20, 39...4646, 6066, 8346, 609, 26, 43, 57, 5830, 8035, 6933, 34, 42508822, 40495, 31, 608016, 25, 3872, 53, 73466328, 37, 86Cell surface:C4b[plasma membrane]FCN2:MASP2dimer:MASP1 dimer[extracellularregion]MASP1 dimer[extracellularregion]thioester-C1010-Q1013-C4B-derivedC4b [extracellularregion]Cell surface:C4b[plasma membrane]C-reactive proteinpentamer:phosphocholine:C1Q[extracellularregion]C4bC2a, C3bBb[plasma membrane]C3b [extracellularregion]Ficolin-3 hexamer[extracellularregion]C3b [extracellularregion]C3b [extracellularregion]C4 bindingprotein:C4bC2a[plasma membrane]CR1:C3b [plasmamembrane]MASP1 dimer[extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]C3b [extracellularregion]Ig Antibody LightChain [extracellularregion]C4B-derived C4c[extracellularregion]MCP, CR1:C4b:C3bcomplexes [plasmamembrane]Cellsurface:C3b:FactorBb [plasma membrane]C5b [extracellularregion]CR1:C3b [plasmamembrane]C4b-binding protein[plasma membrane]MBL subunit[extracellularregion]Complement factor I[extracellularregion]C5b:C6:C7:C8 complex[plasma membrane]C4c, C3f[extracellularregion]C5b:C6:C7 complex[plasma membrane]C4b-binding protein[plasma membrane]C3b [extracellularregion]Cell surface:C4b[plasma membrane]C5b [extracellularregion]C3b:FactorBb:C3b:Properdincomplex [plasmamembrane]MBL subunit[extracellularregion]FCN2:MASPs:Ca2+:FCN2ligand [plasmamembrane]FCN1 ligand [plasmamembrane]deamidated-Q1013-C4B-derivedC4b [extracellularregion]Ficolin-3 hexamer[extracellularregion]Immunoglobulin KappaLight Chain[extracellularregion]MCP:C4b [plasmamembrane]FCN2 ligand [plasmamembrane]Activated C1S[extracellularregion]C3b [extracellularregion]Ig Kappa Light ChainV Region[extracellularregion]FCN3 ligand [plasmamembrane]C8 [extracellularregion]Ig Lamda Light ChainV Region[extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]C3b [extracellularregion]FCN3:MASP2dimer:MASP1 dimer[extracellularregion]Ficolin-3 hexamer[extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]C3b [extracellularregion]C4b [extracellularregion]C3b [extracellularregion]FCN2 subunit[extracellularregion]Ig Heavy Chain VRegion[extracellularregion]FCN3 ligand [plasmamembrane]C5b [extracellularregion]MBL:activatedMASPs:mannose-basedcarbohydrates [plasma membrane]C1Q subunit(C1QA:C1QB:C1QCheterotrimer)[extracellularregion]Cell surface:C4b[plasma membrane]C4b [extracellularregion]Complement factorI:Factor H:C3b[extracellularregion]Complement Factor 4[extracellularregion]Cell surface:C4b[plasma membrane]IgG C region[extracellularregion]Complement factor 4A[extracellularregion]FCN2:MASP2dimer:MASP1 dimer[extracellularregion]MBL subunit[extracellularregion]IgG Heavy Chain[extracellularregion]CR1:C3b [plasmamembrane]MBL-II tetramer[extracellularregion]Cellsurface:C3b:FactorBb [plasma membrane]C3b [extracellularregion]FCN3 subunit[extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]C3b [extracellularregion]C3(H2O)[extracellularregion]CR1:C4b [plasmamembrane]MASP1 dimer[extracellularregion]Activated MASP-2dimer [extracellularregion]MCP:C3b [plasmamembrane]Immunoglobulin KappaLight Chain[extracellularregion]CD59:C5b-C9 [plasmamembrane]Immunoglobulin KappaLight Chain[extracellularregion]FCN2 subunit[extracellularregion]C-reactive proteinpentamer:phosphocholine[plasma membrane]Cellsurface:C3b:Factor Bcomplex [plasmamembrane]C4b [extracellularregion]C4b-bindingprotein:Factor I[plasma membrane]C3(H2O):Factor B[extracellularregion]C3b [extracellularregion]Cell surface:C4b[plasma membrane]C3b [extracellularregion]Activated MASP-1dimer [extracellularregion]Ig Lambda C region[extracellularregion]VTN:C5b:C6:C7:C8:C9[extracellularregion]IgG C region[extracellularregion]MASP2 dimer[extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]Ig Heavy Chain VRegion[extracellularregion]IgG Heavy Chain[extracellularregion]Antigen: antibody:C1 complex [plasmamembrane]Complement factor I[extracellularregion]C3b [extracellularregion]MASP2 dimer[extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]C5b [extracellularregion]Cell surface:C3b[plasma membrane]Ig Heavy Chain VRegion[extracellularregion]FCN2 ligand [plasmamembrane]Cellsurface:C3b:FactorBb [plasma membrane]IgG [extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]C8 [extracellularregion]C5b:C6 complex[extracellularregion]C4B-derived C4c[extracellularregion]Complement factor I[extracellularregion]MASP1 dimer[extracellularregion]C4-bindingprotein:C4b [plasmamembrane]C3(H2O):Factor Bb[extracellularregion]FCN2 subunit[extracellularregion]MCP:C4b [plasmamembrane]Ficolin-2 tetramer[extracellularregion]thioester-C1010-Q1013-C4B-derivedC4b [extracellularregion]MBL-II tetramer[extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]VTN:C5b:C6:C7[extracellularregion]CR1:C4b [plasmamembrane]cytosolC4b [extracellularregion]C5b:C6:C7 complex[extracellularregion]Cell surface:C4b[plasma membrane]FCN1:MASPs:Ca2+:FCN1ligand [plasmamembrane]MCP:C3b [plasmamembrane]Activated MASP-1dimer [extracellularregion]MASP2 dimer[extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]C4 bindingprotein:protein S[plasma membrane]thioester-C1010-Q1013-C4A-derived C4b[extracellularregion]Cell surface:C4b[plasma membrane]C1 complement factor(with activated C1R)[extracellularregion]FCN2 ligand [plasmamembrane]FCN1:MASPs:Ca2+:FCN1ligand [plasmamembrane]Cell surface:C3b[plasma membrane]IgG Heavy Chain[extracellularregion]thioester-C1010-Q1013-C4b[extracellularregion]FCN3:MASP2dimer:MASP1 dimer[extracellularregion]Complement factor I[extracellularregion]Complement factor I[extracellularregion]C4b [extracellularregion]Cellsurface:C3b:FactorBb [plasma membrane]MBL-II:MASP-2dimer:MASP-1 dimercomplex[extracellularregion]ImmunoglobulinLambda Light Chain[extracellularregion]Ig Antibody LightChain [extracellularregion]C4c [extracellularregion]C3b [extracellularregion]C5b:C6:C7 complex[extracellularregion]MBL subunit[extracellularregion]FCN2:MASP2dimer:MASP1 dimer[extracellularregion]CR1:C3bBb [plasmamembrane]MASP1 dimer[extracellularregion]Ficolin-2:activatedMASP-1:activatedMASP-2:Ca2+:ficolinligand [plasmamembrane]C8 [extracellularregion]Cell surface:C4b:C2a[plasma membrane]Activated C1R[extracellularregion]C8 [extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]C5b [extracellularregion]C1 complement factor(with activated C1Rand C1S)[extracellularregion]MASP2 dimer[extracellularregion]MBL subunit[extracellularregion]C1Q subunit(C1QA:C1QB:C1QCheterotrimer)[extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]Cell surface:C4b[plasma membrane]CR1:iC3b [plasmamembrane]deamidated-Q1013-C4A-derivedC4b [extracellularregion]Ig Lambda C region[extracellularregion]MBL-II tetramer[extracellularregion]FCN1:MASP2dimer:MASP1 dimer[extracellularregion]thioester-C1010-Q1013-C4b[extracellularregion]FCN1 subunit[extracellularregion]Cell surface:C4b[plasma membrane]Cell surface:C4b:C2a[plasma membrane]MASP2 dimer[extracellularregion]Antigen-antibodycomplex [plasmamembrane]Cellsurface:FH,FHR3:C3b[plasma membrane]Ficolin-1 tetramer[extracellularregion]MASP1 dimer[extracellularregion]Membrane AttackComplex [plasmamembrane]MCP, CR1:C4b:C3bcomplexes [plasmamembrane]Antigen-antibodycomplex [plasmamembrane]Cellsurface:C3b:FactorBb:Properdin [plasmamembrane]deamidated-Q1013-C4A-derivedC4b [extracellularregion]C3b [extracellularregion]FCN3:MASP2dimer:MASP1 dimer[extracellularregion]CR1:C3bBb, C4bC2acomplexes [plasmamembrane]Ficolin-1:activatedMASP-1:activatedMASP-2:Ca2+:ficolinligand [plasmamembrane]Cell surface:C4b[plasma membrane]Ig Antibody LightChain [extracellularregion]Cell surface:C3b[plasma membrane]deamidated-Q1013-C4B-derivedC4b [extracellularregion]Ficolin-2 tetramer[extracellularregion]C3b [extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]thioester-C1010-Q1013-C4b[extracellularregion]ActivatedC1S:activated C1Rtetramer[extracellularregion]C4c [extracellularregion]C-reactive proteinhomopentamer[extracellularregion]FCN1 ligand [plasmamembrane]Complement factor 4B[extracellularregion]MBL/Ficolin:MASPsbound tocarbohydratepatterns [plasmamembrane]Ficolin-3:activatedMASP-1:activatedMASP-2:Ca2+:ficolinligand [plasmamembrane]Complement factor 3[extracellularregion]C1 complement factor[extracellularregion]C3b [extracellularregion]MBL-II tetramer[extracellularregion]C5b:C6:C7 complex[extracellularregion]VTN:C5b:C6:C7[extracellularregion]MBL-II:MASP-2dimer:MASP-1 dimercomplex[extracellularregion]Cellsurface:C3b:FactorBb:Properdin [plasmamembrane]CR1:C4bC2a [plasmamembrane]Cell surface:C4b[plasma membrane]deamidated-Q1013-C4B-derivedC4b [extracellularregion]C1Q [extracellularregion]thioester-C1010-Q1013-C4B-derivedC4b [extracellularregion]MASP1 dimer[extracellularregion]C4b [extracellularregion]C5b [extracellularregion]MASP2 dimer[extracellularregion]C5b [extracellularregion]iC3b [plasmamembrane]C5b [extracellularregion]Activated MASP-2dimer [extracellularregion]FCN2:MASPs:Ca2+:FCN2ligand [plasmamembrane]IgG [extracellularregion]C3b [extracellularregion]C4b [extracellularregion]C4A-derived C4c[extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]C3c [extracellularregion]Cell surface:C4b:C2a[plasma membrane]Cell surface:C3b[plasma membrane]MASP1 dimer[extracellularregion]C1S:C1R tetramer[extracellularregion]Cell surface:C3b[plasma membrane]Ficolin-1 tetramer[extracellularregion]iC3b [extracellularregion]C1Q [extracellularregion]Antigen: antibody:C1 (activated C1R)complex [plasmamembrane]ImmunoglobulinLambda Light Chain[extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]Factor H:C3b[extracellularregion]Complement factorI:Cellsurface:FH,FHR3:C3b[plasma membrane]Ig Lambda C region[extracellularregion]FCN3:MASPs:Ca2+:FCN3ligand [plasmamembrane]deamidated-Q1013-C4A-derivedC4b [extracellularregion]C4b [extracellularregion]Antigen: antibody:C1 (activated C1Rand C1S) complex[plasma membrane]Cell surface:C4b[plasma membrane]MBL/FCN:activatedMASP:carbohydratepatterns [plasmamembrane]thioester-C1010-Q1013-C4b[extracellularregion]Ficolin-2 tetramer[extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]MBL-II tetramer[extracellularregion]IgG [extracellularregion]Ficolin-1 tetramer[extracellularregion]C1Q subunit(C1QA:C1QB:C1QCheterotrimer)[extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]C5b:C6:C7:C8 complex[plasma membrane]C4-bindingprotein:C4b [plasmamembrane]C4b-binding protein[plasma membrane]deamidated-Q1013-C4A-derivedC4b [extracellularregion]MBL:activatedMASPs:mannose-basedcarbohydrates [plasma membrane]FCN1:MASP2dimer:MASP1 dimer[extracellularregion]Cell surface:C3b[plasma membrane]Cell surface:C4b[plasma membrane]C5b [extracellularregion]C4b [extracellularregion]Cell surface:C4b:C2a[plasma membrane]deamidated-Q1013-C4A-derivedC4b [extracellularregion]MBL bound tomannose-basedcarbohydrates onbacterial surfaces[plasma membrane]FCN3 subunit[extracellularregion]C3(H2O)[extracellularregion]iC3b [plasmamembrane]C3b [extracellularregion]Cellsurface:C3b:FactorBb [plasma membrane]MCP:C3b [plasmamembrane]Host cell surface[plasma membrane]MASP2 dimer[extracellularregion]FCN1 ligand [plasmamembrane]Ig Kappa Light ChainV Region[extracellularregion]Cell surface:C4b:C2a[plasma membrane]MASP1 dimer[extracellularregion]Cell surface:C4b[plasma membrane]C3b [extracellularregion]C3(H2O)[extracellularregion]thioester-C1010-Q1013-C4B-derivedC4b [extracellularregion]Cell surface:C4b:C2a[plasma membrane]MBL-II:ActivatedMASP-1dimer:ActivatedMASP-2 dimer complex[extracellularregion]C3b [extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]C4b-binding protein[plasma membrane]thioester-C1010-Q1013-C4A-derived C4b[extracellularregion]MBL-II:ActivatedMASP-1dimer:ActivatedMASP-2 dimer complex[extracellularregion]C1S:activated C1Rtetramer[extracellularregion]Ficolin-3 hexamer[extracellularregion]Ig Lamda Light ChainV Region[extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]Complement factor 5[extracellularregion]deamidated-Q1013-C4B-derivedC4b [extracellularregion]C4b [extracellularregion]C4b:C2a:C3b [plasmamembrane]MASP2 dimer[extracellularregion]FCN1 subunit[extracellularregion]C3b [extracellularregion]C3b [extracellularregion]MBL-II:MASP-2dimer:MASP-1 dimercomplex[extracellularregion]Cell surface:C3b[plasma membrane]Factor H:Host cellsurface [plasmamembrane]C4b with hydrolysedthioester[extracellularregion]C1Q subunit(C1QA:C1QB:C1QCheterotrimer)[extracellularregion]DAF:C4bC2a [plasmamembrane]C3(H2O)[extracellularregion]FCN1 subunit[extracellularregion]DAF:C3 convertasecomplexes [plasmamembrane]DAF:C3bBb [plasmamembrane]Ig Kappa Light ChainV Region[extracellularregion]C1Q [extracellularregion]Ficolin-2 tetramer[extracellularregion]MASP2 dimer[extracellularregion]DAF:C4b [plasmamembrane]FCN3:MASPs:Ca2+:FCN3ligand [plasmamembrane]deamidated-Q1013-C4B-derivedC4b [extracellularregion]CR1:C4b [plasmamembrane]C4b [extracellularregion]FCN3 ligand [plasmamembrane]C3b [extracellularregion]FCN1:MASP2dimer:MASP1 dimer[extracellularregion]FCN3 subunit[extracellularregion]deamidated-Q1013-C4A-derivedC4b [extracellularregion]C4b [extracellularregion]Host cell surface[plasma membrane]Cell surface:C4b:C2a[plasma membrane]deamidated-Q1013-C4B-derivedC4b [extracellularregion]ImmunoglobulinLambda Light Chain[extracellularregion]C4b [extracellularregion]thioester-C1010-Q1013-C4A-derived C4b[extracellularregion]FCN3 subunit[extracellularregion]C4A-derived C4c[extracellularregion]C8 [extracellularregion]Antigen-antibodycomplex [plasmamembrane]DAF:C3b [plasmamembrane]IgG C region[extracellularregion]Ficolin-1 tetramer[extracellularregion]Cellsurface:FH,FHR3:C3bBb[plasma membrane]Activated C1R[extracellularregion]Factor H:C3b[extracellularregion]C3b [extracellularregion]FCN1 subunit[extracellularregion]Cellsurface:C3b:FactorBb [plasma membrane]MCP:C4b [plasmamembrane]MBL bound tomannose-basedcarbohydrates onbacterial surfaces[plasma membrane]Cellsurface:FH,FHR3:C3b[plasma membrane]C4b, C3b [plasmamembrane]thioester-C1010-Q1013-C4A-derived C4b[extracellularregion]C1Q [extracellularregion]C4b [extracellularregion]C4b [extracellularregion]C4b-binding protein[plasma membrane]FCN2 subunit[extracellularregion]Ig Lamda Light ChainV Region[extracellularregion]Factor I:MCP,CR1:C4b, C3bcomplexes [plasmamembrane]Ig heavy chain V-IIIregion TEI[extracellularregion]Ca2+Ig kappa chain V-Iregion HK101[extracellularregion]CFB(260-764) [plasmamembrane]CR1 [plasmamembrane]C3 beta chain[extracellularregion]CR1:C3bFCN2 [extracellularregion]dNQ-C4A(757-1446)[extracellularregion]MASP2-1[extracellularregion]Ig heavy chain V-IIIregion GAL[extracellularregion]C7(22-843)[extracellularregion]IGHG4(1-327)[extracellularregion]Ig lambda chain V-VIregion SUT[extracellularregion]IGHV(1-?)[extracellularregion]Ig kappa chain V-IVregion STH[extracellularregion]Heparins [plasmamembrane]PCho [plasmamembrane]C7(22-843)[extracellularregion]Ig kappa chain V-IIIregion VH[extracellularregion]C4A gamma[extracellularregion]Complement factor 3dNQ-C4B(757-1446)[extracellularregion]C4A beta[extracellularregion]C3 beta chain[extracellularregion]C4A gamma[extracellularregion]Ig kappa chain V-IIIregion Ti[extracellularregion]C4BPB [plasmamembrane]Ig kappa chain V-IIIregion HAH[extracellularregion]C5 beta[extracellularregion]C4A gamma[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]C4A gamma[extracellularregion]Ig kappa chain V-IIIregion HIC[extracellularregion]C2aIg heavy chain V-IIIregion DOB[extracellularregion]C3 beta chain[extracellularregion]C4 bindingprotein:C4bC2aC3 beta chain[extracellularregion]C4B gamma[extracellularregion]C3 beta chain[extracellularregion]Ig kappa chain V-Iregion Ni[extracellularregion]dNQ-C3(672-1663)[extracellularregion]Ig heavy chain V-IIregion COR[extracellularregion]Ig kappa chain V-IIIregion NG9[extracellularregion]Ig lambda chain V-Iregion WAH[extracellularregion]Ig kappa chain V-Iregion AU[extracellularregion]Cellsurface:C3b:FactorBbIg kappa chain V-IIIregion HAH[extracellularregion]C5 beta[extracellularregion]IGHG3 [extracellularregion]IGLV2-11(1-?)[extracellularregion]CFI(19-335)[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]Ig lambda chain V-IIregion BOH[extracellularregion]Ig heavy chain V-IIIregion TIL[extracellularregion]C5b alpha'[extracellularregion]Ig kappa chain V-IIIregion SIE[extracellularregion]Ig lambda chain V-IIregion WIN[extracellularregion]C4 activatorIg kappa chain V-IVregion STH[extracellularregion]IGLC3(?-106)[extracellularregion]Ig lambda chain V-Iregion WAH[extracellularregion]IGLV(23-?)[extracellularregion]N-acetyl-D-glucosamine[plasma membrane]C3b alpha'[extracellularregion]IGLV3-22(1-?)[extracellularregion]C3aC3 beta chain[extracellularregion]Ig heavy chain V-Iregion Mot[extracellularregion]C3 beta chain[extracellularregion]Ig kappa chain V-IIIregion VG[extracellularregion]C2a [extracellularregion]Ca2+ [extracellularregion]thioester-C1010-Q1013-C4bIg kappa chain V-Iregion Wes[extracellularregion]Ig kappa chain V-IIregion RPMI 6410[extracellularregion]C6 [extracellularregion]Cellsurface:C3b:FactorBbIg kappa chain V-IIIregion NG9[extracellularregion]Ig heavy chain V-IIIregion BUT[extracellularregion]Ig heavy chain V-IIIregion NIE[extracellularregion]IGLV2-33(1-?)[extracellularregion]Factor H:C3bFCN1:MASP2dimer:MASP1 dimerdNQ-C4A(757-1446)[extracellularregion]Ig kappa chain V-IIIregion Ti[extracellularregion]Ig kappa chain V-IIIregion GOL[extracellularregion]C4A beta[extracellularregion]Ig kappa chain V-IVregion B17[extracellularregion]C4A gamma[extracellularregion]Ig kappa chain V-Iregion Scw[extracellularregion]IGLV1-44(1-?)[extracellularregion]Ig kappa chain V-IIIregion VG[extracellularregion]1,3-beta-D-glucan[plasma membrane]IGLV4-3(1-?)[extracellularregion]MBL2 [extracellularregion]IGLC1(1-105)[extracellularregion]CR1:iC3bIg lambda chain V-VIregion NIG-48[extracellularregion]C1QC [extracellularregion]FCN1 [extracellularregion]CD55MBL:activatedMASPs:mannose-basedcarbohydratesIg lambda chain V-Iregion MEM[extracellularregion]Ig kappa chain V-IVregion B17[extracellularregion]Ig kappa chain V-Iregion WEA[extracellularregion]Ca2+ [extracellularregion]Ig heavy chain V-Iregion ND[extracellularregion]Ig lambda chain V-VIregion NIG-48[extracellularregion]FCN1 [extracellularregion]Ig lambda chain V-Vregion DEL[extracellularregion]C4B alpha chainfragment b[extracellularregion]C8B [extracellularregion]dNQ-C3(672-1663)[extracellularregion]CFB(260-764)[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]C4A beta[extracellularregion]Ig lambda chain V-IIregion TRO[extracellularregion]C7(22-843)C5 beta[extracellularregion]Ig kappa chain V-IIregion TEW[extracellularregion]IGLV10-54(1-?)[extracellularregion]Ig heavy chain V-IIIregion GAL[extracellularregion]Ig lambda chain V-VIregion EB4[extracellularregion]C4BPB [plasmamembrane]C4A beta[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]IGLV1-36(1-?)[extracellularregion]C4A beta[extracellularregion]C3b alpha'[extracellularregion]C5b alpha'[extracellularregion]IGKC(1-106)[extracellularregion]Ig heavy chain V-IIregion SESS[extracellularregion]Complement factorI:Factor H:C3bIg kappa chain V-Iregion Scw[extracellularregion]Ig heavy chain V-IIregion DAW[extracellularregion]IGLV4-69(1-?)[extracellularregion]C4 bindingprotein:protein SIg heavy chain V-Iregion HG3[extracellularregion]C4A beta[extracellularregion]C3bC3c alpha' chainfragment 1 precursor[extracellularregion]Ig kappa chain V-Iregion Ni[extracellularregion]CR1:C3bBb, C4bC2acomplexesC3 beta chain[extracellularregion]CFH [extracellularregion]Ig heavy chain V-IIregion MCE[extracellularregion]IGKV4-1(21-?)[extracellularregion]Ig kappa chain Vregion EV15[extracellularregion]IGLV1-40(1-?)[extracellularregion]C4A beta[extracellularregion]Ig lambda chain V-IIregion VIL[extracellularregion]Cellsurface:FH,FHR3:C3bIGLV2-18(1-?)[extracellularregion]C4A gamma[extracellularregion]Ig heavy chain V-Iregion HG3[extracellularregion]Ig heavy chain V-Iregion WOL[extracellularregion]Ig kappa chain V-IIregion MIL[extracellularregion]Ca2+ [extracellularregion]MASP1(20-448)[extracellularregion]C3b alpha'[extracellularregion]C4bC2a, C3bBbIg lambda chain V-IIregion TOG[extracellularregion]MASP1(449-699)[extracellularregion]Ig lambda chain V-IVregion Kern[extracellularregion]C9(22-559)[extracellularregion]C4A alpha b[extracellularregion]Ig lambda chain V-IIregion TOG[extracellularregion]MASP2-1[extracellularregion]IGHG2(1-326)[extracellularregion]Ig heavy chain V-IIregion MCE[extracellularregion]CRP(19-224)[extracellularregion]Ig heavy chain V-IIIregion CAM[extracellularregion]Ig heavy chain V-IIregion NEWM[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]Ig kappa chain V-IIIregion WOL[extracellularregion]Ig kappa chain V-Iregion EU[extracellularregion]Ig heavy chain V-Iregion SIE[extracellularregion]1,3-beta-D-glucan[plasma membrane]C5 alpha[extracellularregion]C4A gamma[extracellularregion]Ig lambda chain V-IVregion Bau[extracellularregion]Ig kappa chain V-IVregion Len[extracellularregion]FCN3 [extracellularregion]C4B beta[extracellularregion]Ig heavy chain V-IIIregion POM[extracellularregion]Ig lambda chain V-VIregion NIG-48[extracellularregion]IGLC1(1-105)[extracellularregion]C9(22-559)[extracellularregion]IGLV3-22(1-?)[extracellularregion]C3 beta chain[extracellularregion]Ig kappa chain V-Iregion AG[extracellularregion]Ig lambda chain V-Iregion NEW[extracellularregion]Ig heavy chain V-IIIregion WEA[extracellularregion]MBL bound tomannose-basedcarbohydrates onbacterial surfacesC5 beta[extracellularregion]CFH [extracellularregion]Ig kappa chain V-IIregion FR[extracellularregion]Ig heavy chain V-IIIregion TIL[extracellularregion]IGLV5-45(1-?)[extracellularregion]Ig heavy chain V-IIIregion HIL[extracellularregion]C4A beta[extracellularregion]Ig kappa chain V-Iregion Mev[extracellularregion]N-acetyl-D-glucosamine[plasma membrane]C4A beta[extracellularregion]IGLV10-54(1-?)[extracellularregion]C4BPB [plasmamembrane]Ig kappa chain V-Iregion Bi[extracellularregion]Complement factor 5C3f [extracellularregion]MASP2-1[extracellularregion]Ig lambda chain V-IVregion X[extracellularregion]D-fucose [plasmamembrane]C3b alpha'[extracellularregion]C2a [extracellularregion]CFI(340-583)[extracellularregion]IgH heavy chainV-III region VH26precursor[extracellularregion]Ig lambda chain V-IIregion BOH[extracellularregion]IGLV4-60(1-?)[extracellularregion]C3adNQ-C4B(757-1446)[extracellularregion]Ig lambda chain V-Iregion HA[extracellularregion]C4B beta[extracellularregion]C8G [extracellularregion]CFB(260-764) [plasmamembrane]Ig heavy chain V-IIIregion JON[extracellularregion]Ig kappa chain V-Iregion Rei[extracellularregion]C3b alpha'[extracellularregion]C8G [extracellularregion]VTN:C5b:C6:C7:C8:C9Properdin oligomerIg heavy chain V-IIregion MCE[extracellularregion]C3 beta chain[extracellularregion]Ig kappa chain V-Iregion AU[extracellularregion]C3c alpha' chainfragment 2[extracellularregion]C4B beta[extracellularregion]CFH [extracellularregion]Ig heavy chain V-IIIregion WEA[extracellularregion]IGHG4(1-327)[extracellularregion]C6 [extracellularregion]C3bMCP:C4bC6Ig kappa chain V-IIregion TEW[extracellularregion]C5b alpha'[extracellularregion]Cell surface:C4b:C2aC4A beta[extracellularregion]IGLV1-44(1-?)[extracellularregion]Ig lambda chain V-Iregion WAH[extracellularregion]IGLC6(?-106)[extracellularregion]Ig kappa chain V-IIIregion GOL[extracellularregion]CFI(340-583)[extracellularregion]C8G [extracellularregion]IGLV7-43(1-?)[extracellularregion]C4A beta[extracellularregion]Ig heavy chain V-IIIregion JON[extracellularregion]Ig lambda chain V-Iregion VOR[extracellularregion]C8G [extracellularregion]Ig kappa chain V-Iregion Roy[extracellularregion]IgH heavy chainV-III region VH26precursor[extracellularregion]C4B alpha chainfragment b[extracellularregion]Host cell surfaceMASP1(20-699)[extracellularregion]IGLV2-11(1-?)[extracellularregion]C4B beta[extracellularregion]C8B [extracellularregion]Ig heavy chain V-IIIregion TRO[extracellularregion]IGLV1-44(1-?)[extracellularregion]C7(22-843)[extracellularregion]IGLC6(?-106)[extracellularregion]C4b-bindingprotein:Factor IC5 convertasesC2aC9(22-559)C4A alpha b[extracellularregion]C4B alpha3[extracellularregion]C4A gamma[extracellularregion]MASP2-1(16-444)[extracellularregion]C4A alpha b[extracellularregion]1,3-beta-D-glucan[plasma membrane]FCN2 [extracellularregion]C3b alpha'[extracellularregion]C4A beta[extracellularregion]Ig heavy chain V-IIIregion NIE[extracellularregion]C5b:C6:C7:C8 complexC4A alpha4 fragment[extracellularregion]MASP1(20-699)[extracellularregion]Ig lambda chain V-IVregion Bau[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]CD59Ig heavy chain V-IIIregion KOL[extracellularregion]Ig lambda chainV-VII region MOT[extracellularregion]C4B beta[extracellularregion]C6 [extracellularregion]IGLV10-54(1-?)[extracellularregion]Ig lambda chain V-Iregion EPS[extracellularregion]IGLV8-61(1-?)[extracellularregion]Ig kappa chain V-IIIregion SIE[extracellularregion]IGLV7-46(1-?)[extracellularregion]Antigen: antibody:C1 (activated C1Rand C1S) complexIGLV8-61(1-?)[extracellularregion]Ig heavy chain V-IIIregion CAM[extracellularregion]IGLC7(?-106)[extracellularregion]MASP2-1[extracellularregion]Ig heavy chain V-IIregion OU[extracellularregion]C4b with hydrolysedthioesterC3 beta chain[extracellularregion]Ig kappa chain V-Iregion Lay[extracellularregion]IGHG1(1-330)[extracellularregion]Ig kappa chain V-Iregion Ka[extracellularregion]C4B gamma[extracellularregion]IGHV7-81(1-?)[extracellularregion]Ig lambda chain V-IIregion NIG-84[extracellularregion]IGKV1-5(23-?)[extracellularregion]MASP1(20-699)[extracellularregion]Ig heavy chain V-IIregion WAH[extracellularregion]C8A [extracellularregion]IGHG2(1-326)[extracellularregion]C3c alpha' chainfragment 2 [plasmamembrane]C4B beta[extracellularregion]IGHG1(1-330)[extracellularregion]C5 beta[extracellularregion]Ig lambda chain V-IVregion Hil[extracellularregion]C8G [extracellularregion]Ig lambda chain V-IVregion Hil[extracellularregion]FCN2 [extracellularregion]Ig heavy chain V-IIIregion WAS[extracellularregion]Ig lambda chain Vregion 4A[extracellularregion]IGLV7-46(1-?)[extracellularregion]C4A beta[extracellularregion]C7(22-843)[extracellularregion]Ca2+ [extracellularregion]MCP:C3bdNQ-C3(672-1663)[extracellularregion]C3cIg kappa chain V-Iregion CAR[extracellularregion]C5 beta[extracellularregion]Ig lambda chain V-IVregion MOL[extracellularregion]Ig kappa chain V-IVregion Len[extracellularregion]Cellsurface:C3b:FactorBb:ProperdinC4B gamma[extracellularregion]MASP1(20-699)[extracellularregion]C4A gamma[extracellularregion]Ig kappa chain V-Iregion EU[extracellularregion]Ig lambda chain V-IIregion NEI[extracellularregion]CD59:C5b-C9Cell surface:C4bMASP2-1[extracellularregion]FH, FHR-3CD46 [plasmamembrane]Ig lambda chain V-IIregion NIG-58[extracellularregion]C4A gamma[extracellularregion]C4A alpha4 fragment[extracellularregion]CFB(260-764) [plasmamembrane]IGLV3-27(1-?)[extracellularregion]C3 beta chain[plasma membrane]Ig heavy chain V-IIregion COR[extracellularregion]C3c alpha' chainfragment 1 precursor[plasma membrane]Ig heavy chain V-Iregion SIE[extracellularregion]C3b alpha'[extracellularregion]IGLV3-27(1-?)[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]IGLV1-40(1-?)[extracellularregion]Ig lambda chain V-IVregion MOL[extracellularregion]IGLV4-60(1-?)[extracellularregion]Ig heavy chain V-IIregion NEWM[extracellularregion]Ig kappa chain V-IIregion RPMI 6410[extracellularregion]Ig lambda chain V-IIregion VIL[extracellularregion]Ig kappa chain V-IIIregion HAH[extracellularregion]Lipoteichoic acid[plasma membrane]C5aIg lambda chain V-Iregion HA[extracellularregion]Ig kappa chain V-IIIregion WOL[extracellularregion]Ig kappa chain V-IIregion RPMI 6410[extracellularregion]C1QB(26-251)[extracellularregion]C4B alpha3[extracellularregion]CFB(26-764)[extracellularregion]Ig kappa chain V-Iregion Walker[extracellularregion]C3 beta chain[extracellularregion]C4A beta[extracellularregion]MASP1(20-699)[extracellularregion]Ig heavy chain V-IIregion SESS[extracellularregion]Ig kappa chain V-Iregion HK101[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]CFB(260-764) [plasmamembrane]Complement Factor 4IGHG3 [extracellularregion]Ig lambda chain V-VIregion AR[extracellularregion]C3b alpha'[extracellularregion]CD46 [plasmamembrane]Ig lambda chain V-IVregion Kern[extracellularregion]Ig heavy chain V-IIregion OU[extracellularregion]C4A gamma[extracellularregion]Ig lambda chain V-Iregion VOR[extracellularregion]C4b, C3bIg kappa chain V-Iregion WAT[extracellularregion]C3 beta chain[extracellularregion]N-acetylgalactosamine[plasma membrane]Ig kappa chain V-IIIregion HIC[extracellularregion]Ig heavy chain V-IIregion ARH-77[extracellularregion]N-acetylgalactosamine[plasma membrane]Ig heavy chain V-IIIregion TUR[extracellularregion]Ig kappa chain V-IIIregion CLL[extracellularregion]C4B alpha chainfragment b[extracellularregion]C4d, iC3bIGLV7-46(1-?)[extracellularregion]Ig lambda chain V-IIregion BUR[extracellularregion]FCN1:MASPs:Ca2+:FCN1ligandC4B beta[extracellularregion]Antigen: antibody:C1 (activated C1R)complexCR1 [plasmamembrane]Cell surfaceIg heavy chain V-IIIregion JON[extracellularregion]C4A gamma[extracellularregion]IGLV1-40(1-?)[extracellularregion]Ig kappa chain V-IIIregion SIE[extracellularregion]Cell surface:C4bC4A beta[extracellularregion]Ig lambda chain V-Iregion NEWM[extracellularregion]IGHG4(1-327)[extracellularregion]C1S N-terminalfragment[extracellularregion]IGLV7-43(1-?)[extracellularregion]C2aIg kappa chain V-IIIregion VG[extracellularregion]Ig kappa chain V-Iregion Hau[extracellularregion]Cell surfaceComplement factor DLipoteichoic acid[plasma membrane]Ig kappa chain V-Iregion DEE[extracellularregion]Ig lambda chain V-VIregion AR[extracellularregion]C8B [extracellularregion]C5 beta[extracellularregion]C4A beta[extracellularregion]MBL2 [extracellularregion]C1QA [extracellularregion]IGLV2-23(1-?)[extracellularregion]C3b alpha'[extracellularregion]C3b alpha'[extracellularregion]C3bIGLV3-25(1-?)[extracellularregion]Ig kappa chain V-IIIregion POM[extracellularregion]Ig heavy chain V-IIIregion BUR[extracellularregion]Ig lambda chain V-IIregion BO[extracellularregion]N-acetylgalactosamine[plasma membrane]Sialic acid [plasmamembrane]Ig kappa chain V-IIIregion IARC/BL41[extracellularregion]Ig lambda chain V-IIregion MGC[extracellularregion]Ig heavy chain V-Iregion HG3[extracellularregion]C-reactive proteinpentamer:phosphocholine:C1QBacterialmannose-basedcarbohydrate surfacepatternDAF:C3bC4B gamma[extracellularregion]Ig heavy chain V-Iregion WOL[extracellularregion]MASP2-1[extracellularregion]C5b alpha'[extracellularregion]C4B gamma[extracellularregion]iC3bC3 beta chain[extracellularregion]Ig lambda chainV-III region SH[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]FCN1 ligandIg kappa chain V-Iregion CAR[extracellularregion]C3b alpha'[extracellularregion]C6 [extracellularregion]Ig heavy chain V-Iregion ND[extracellularregion]C8B [extracellularregion]C1QC [extracellularregion]Ig heavy chain V-Iregion EU[extracellularregion]IGKV4-1(21-?)[extracellularregion]C1QB(26-251)[extracellularregion]C8B [extracellularregion]C3b:FactorBb:C3b:ProperdincomplexMASP1(20-699)[extracellularregion]C2Ig heavy chain V-IIregion ARH-77[extracellularregion]Ig kappa chain V-Iregion HK101[extracellularregion]Ig lambda chain V-Iregion EPS[extracellularregion]C4B alpha4 fragment[extracellularregion]C4A alpha3[extracellularregion]CR1Ig lambda chain Vregion 4A[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]FCN1 [extracellularregion]Ig heavy chain V-Iregion Mot[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]MASP1(20-699)[extracellularregion]Ca2+ [extracellularregion]C8A [extracellularregion]Ig kappa chain V-IIIregion Ti[extracellularregion]Ig kappa chain Vregion EV15[extracellularregion]Ig kappa chain V-Iregion WEA[extracellularregion]Ig kappa chain V-Iregion Gal[extracellularregion]C1QB(26-251)[extracellularregion]Ig kappa chain V-IIIregion POM[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]Ig kappa chain V-IIIregion NG9[extracellularregion]Ig lambda chain V-IIregion NIG-84[extracellularregion]IGLV5-37(1-?)[extracellularregion]Ig lambda chainV-III region LOI[extracellularregion]Ig heavy chain V-IIregion HE[extracellularregion]C4A gamma[extracellularregion]CFB(260-764) [plasmamembrane]MASP2-1(445-686)[extracellularregion]IGLV(23-?)[extracellularregion]Ig lambda chain V-IIregion BOH[extracellularregion]IGLV2-33(1-?)[extracellularregion]C4A gamma[extracellularregion]Ig lambda chain V-IIregion BO[extracellularregion]C3 beta chain[extracellularregion]Factor I:MCP,CR1:C4b, C3bcomplexesIg kappa chain V-Iregion OU[extracellularregion]H2OC4B beta[extracellularregion]Ig heavy chain V-IIregion ARH-77[extracellularregion]Heparins [plasmamembrane]Ig kappa chain V-Iregion Scw[extracellularregion]C4BPB [plasmamembrane]C4B beta[extracellularregion]C2a [extracellularregion]Ig lambda chainV-III region SH[extracellularregion]Ig kappa chain V-Iregion Lay[extracellularregion]C4B beta[extracellularregion]Ig lambda chain V-Iregion EPS[extracellularregion]CFB(26-259)C3b alpha'[extracellularregion]MASP2-1(445-686)[extracellularregion]C4B beta[extracellularregion]MBL-II:MASP-2dimer:MASP-1 dimercomplexC4B beta[extracellularregion]Ig lambda chain V-Iregion HA[extracellularregion]C4B gamma[extracellularregion]CR1 [plasmamembrane]CFI(19-335)C4cIg kappa chain V-IVregion JI[extracellularregion]IGLV3-12(1-?)[extracellularregion]Ig kappa chain V-IIIregion HIC[extracellularregion]11xCbxE-PROS1[extracellularregion]Ig kappa chain V-Iregion Roy[extracellularregion]Ig heavy chain V-IIregion SESS[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]Ig kappa chain V-Iregion Gal[extracellularregion]IGLV3-22(1-?)[extracellularregion]Ig heavy chain V-IIIregion BUR[extracellularregion]C3 beta chain[plasma membrane]Ig lambda chain V-Iregion NEW[extracellularregion]Ig lambda chain V-IVregion X[extracellularregion]Ig heavy chain V-IIIregion POM[extracellularregion]C5b alpha'[extracellularregion]IGLV4-69(1-?)[extracellularregion]Cellsurface:C3b:Factor BcomplexC3b alpha'[extracellularregion]C7(22-843)[extracellularregion]IGHG2(1-326)[extracellularregion]Ig heavy chain V-IIIregion LAY[extracellularregion]Ig lambda chain V-IIregion MGC[extracellularregion]Sialic acid [plasmamembrane]C3 convertasesiC3bC3(H2O):Factor BC4A gamma[extracellularregion]Ig heavy chain V-IIIregion TRO[extracellularregion]FCN3 [extracellularregion]IGLV4-69(1-?)[extracellularregion]C8A [extracellularregion]FCN2:MASPs:Ca2+:FCN2ligandC9(22-559)[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]C1S(16-688)[extracellularregion]IGKV1-5(23-?)[extracellularregion]Ig kappa chain V-IVregion B17[extracellularregion]FCN3:MASPs:Ca2+:FCN3ligandIg lambda chain V-IIregion VIL[extracellularregion]C3 beta chain[extracellularregion]Ig lambda chain V-IIregion NIG-84[extracellularregion]CD46 [plasmamembrane]C4A beta[extracellularregion]N-acetyl-D-glucosamine[plasma membrane]Ig lambda chain V-VIregion EB4[extracellularregion]Membrane AttackComplexC5b alpha'[extracellularregion]IGLV3-25(1-?)[extracellularregion]CFHCa2+ [extracellularregion]Ig heavy chain V-IIIregion BRO[extracellularregion]CD55 [plasmamembrane]Ig lambda chain V-IIregion NEI[extracellularregion]IGLV(23-?)[extracellularregion]IGLV11-55(1-?)[extracellularregion]Ig kappa chain V-IIregion GM607[extracellularregion]C3 beta chain[extracellularregion]Ig lambda chain V-IVregion Bau[extracellularregion]IGLV5-45(1-?)[extracellularregion]Ig kappa chain V-IIIregion CLL[extracellularregion]Ig lambda chain V-Iregion NEW[extracellularregion]IGLV3-16(1-?)[extracellularregion]C4B beta[extracellularregion]C3b alpha'[extracellularregion]Ig lambda chain V-IIregion WIN[extracellularregion]Ig kappa chain V-IIIregion B6[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]Ig kappa chain V-Iregion WAT[extracellularregion]IGLC7(?-106)[extracellularregion]C4B gamma[extracellularregion]CD59 [plasmamembrane]C1R C-terminalfragment[extracellularregion]C4B alpha[extracellularregion]Cellsurface:FH,FHR3:C3bBbCFB(26-764)[extracellularregion]FCN3 ligandFCN2:MASP2dimer:MASP1 dimerC3 beta chain[extracellularregion]IGKC(1-106)[extracellularregion]Ig lambda chain V-Iregion NIG-64[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]IGLV2-23(1-?)[extracellularregion]C4B gamma[extracellularregion]C4B alpha chainfragment b[extracellularregion]C3b alpha'[extracellularregion]Ig kappa chain V-Iregion Daudi[extracellularregion]C2bIg kappa chain V-IIIregion GOL[extracellularregion]Ig lambda chain V-IVregion X[extracellularregion]Ig heavy chain V-IIIregion TUR[extracellularregion]Ig lambda chain V-Iregion BL2[extracellularregion]C4BPA [plasmamembrane]C3(H2O)C4B alpha4 fragment[extracellularregion]Ig kappa chain V-Iregion Daudi[extracellularregion]C9(22-559)C3dgIg heavy chain V-IIregion HE[extracellularregion]Ig kappa chain V-Iregion Bi[extracellularregion]CR1 [plasmamembrane]Ig heavy chain V-IIIregion ZAP[extracellularregion]C4A gamma[extracellularregion]C3b alpha'[extracellularregion]C5b:C6:C7 complexC4BPA [plasmamembrane]C3 beta chain[extracellularregion]C4-bindingprotein:C4bdNQ-C4B(757-1446)[extracellularregion]IGLV3-12(1-?)[extracellularregion]C4c, C3fC4B gamma[extracellularregion]C2a [extracellularregion]Ig heavy chain V-IIregion OU[extracellularregion]Ig kappa chain V-IVregion STH[extracellularregion]Ig heavy chain V-IIregion HE[extracellularregion]C3 beta chain[extracellularregion]C4B gamma[extracellularregion]MASP2-1[extracellularregion]IgH heavy chainV-III region VH26precursor[extracellularregion]Ig kappa chain V-IIregion MIL[extracellularregion]C1QC [extracellularregion]Sialic acid [plasmamembrane]IGLV2-18(1-?)[extracellularregion]C4B gamma[extracellularregion]Ig lambda chain V-IIregion MGC[extracellularregion]Ig lambda chain V-Iregion MEM[extracellularregion]C4A beta[extracellularregion]C4A beta[extracellularregion]Ig heavy chain V-IIIregion HIL[extracellularregion]C6 [extracellularregion]Ig heavy chain V-Iregion EU[extracellularregion]IGLC7(?-106)[extracellularregion]Ig heavy chain V-IIIregion BRO[extracellularregion]IGLC6(?-106)[extracellularregion]C3b alpha'[extracellularregion]IGLV3-12(1-?)[extracellularregion]IGLV3-16(1-?)[extracellularregion]Ig heavy chain V-IIregion NEWM[extracellularregion]thioester-C1010-Q1013-C4bC4A beta[extracellularregion]C4B beta[extracellularregion]Sialic acid [plasmamembrane]IGLV5-37(1-?)[extracellularregion]MBL2 [extracellularregion]CR1 [plasmamembrane]CFB(260-764) [plasmamembrane]C3 beta chain[extracellularregion]Antigen: antibody:C1 complexIGKVA18(21-?)[extracellularregion]C4BPA [plasmamembrane]C3 beta chain[extracellularregion]FCN2 ligandIGLV8-61(1-?)[extracellularregion]Ig heavy chain V-IIregion WAH[extracellularregion]C3b alpha'[extracellularregion]FCN2 [extracellularregion]Ig kappa chain V-IIregion FR[extracellularregion]Ig lambda chainV-III region LOI[extracellularregion]C4A beta[extracellularregion]Ig lambda chain V-IIregion TRO[extracellularregion]CFI(340-583)[extracellularregion]Ig kappa chain V-Iregion BAN[extracellularregion]MCP, CR1:C4b:C3bcomplexesC4B beta[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]C3b alpha'[extracellularregion]VTN:C5b:C6:C7C4A gamma[extracellularregion]Ig kappa chain V-Iregion WEA[extracellularregion]Ig lambda chain V-IIregion BUR[extracellularregion]Complement factorI:Cellsurface:FH,FHR3:C3bC1S(16-688)[extracellularregion]Ig heavy chain V-IIIregion HIL[extracellularregion]C1QA [extracellularregion]MBL2 [extracellularregion]MASP1(20-699)[extracellularregion]CFDN-acetyl-D-glucosamine[plasma membrane]VTN(20-?)[extracellularregion]Complement factor IIg kappa chain V-Iregion AU[extracellularregion]FCN1 [extracellularregion]Ig kappa chain V-IIIregion IARC/BL41[extracellularregion]Ig lambda chain V-IIregion NIG-58[extracellularregion]IGLV2-11(1-?)[extracellularregion]C4A gamma[extracellularregion]Ig kappa chain V-IVregion JI[extracellularregion]C3c alpha' chainfragment 2 [plasmamembrane]Ig lambda chain V-VIregion AR[extracellularregion]Ig kappa chain V-IIregion Cum[extracellularregion]dNQ-C3(672-1663)[extracellularregion]IGKV1-5(23-?)[extracellularregion]C1QB(26-251)[extracellularregion]C3b alpha'[extracellularregion]Ig kappa chain V-Iregion AG[extracellularregion]Ig kappa chain V-Iregion DEE[extracellularregion]C5b:C6 complexC3 beta chain[extracellularregion]C1S C-terminalfragment[extracellularregion]C3c alpha' chainfragment 1[extracellularregion]Ig lambda chain V-VIregion WLT[extracellularregion]Lipoteichoic acid[plasma membrane]Ca2+ [extracellularregion]Ig kappa chain V-Iregion Kue[extracellularregion]C1QC [extracellularregion]Ig lambda chain V-Iregion NEWM[extracellularregion]C4dC4A gamma[extracellularregion]Ig lambda chain V-IIregion TRO[extracellularregion]IGLV1-36(1-?)[extracellularregion]D-fucose [plasmamembrane]IGLV2-23(1-?)[extracellularregion]Ig heavy chain V-IIIregion WEA[extracellularregion]C7(22-843)[extracellularregion]Ig heavy chain V-IIIregion LAY[extracellularregion]Ig heavy chain V-IIIregion CAM[extracellularregion]Ig kappa chain V-IIregion Cum[extracellularregion]Ig lambda chainV-III region SH[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]IGLC2(?-106)[extracellularregion]C3 beta chain[extracellularregion]CFB(260-764)CFI(19-335)[extracellularregion]C4B gamma[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]C3b alpha'[extracellularregion]C3b alpha'[extracellularregion]Ig kappa chain V-Iregion Ka[extracellularregion]C4 alpha[extracellularregion]Ig lambda chain V-VIregion WLT[extracellularregion]Ig lambda chainV-III region LOI[extracellularregion]C2a [extracellularregion]Ig kappa chain V-Iregion Gal[extracellularregion]C1QA [extracellularregion]Cell surface:C3bIg lambda chain V-Iregion NEWM[extracellularregion]C4B gamma[extracellularregion]Ig lambda chain V-Iregion BL2[extracellularregion]Cell surface:C3bC8A [extracellularregion]Ig lambda chain V-Iregion NIG-64[extracellularregion]Ig heavy chain V-IIIregion TEI[extracellularregion]C4A gamma[extracellularregion]Ig heavy chain V-IIIregion DOB[extracellularregion]C3 alpha chain[extracellularregion]Factor H:Host cellsurfaceIg kappa chain V-IIregion GM607[extracellularregion]MASP1(20-448)[extracellularregion]C3 beta chain[extracellularregion]IGHV7-81(1-?)[extracellularregion]Ca2+ [extracellularregion]IGLV5-37(1-?)[extracellularregion]C4B beta[extracellularregion]C4B gamma[extracellularregion]C3(H2O)C4B beta[extracellularregion]C1R(18-705)[extracellularregion]C5b alpha'[extracellularregion]C6 [extracellularregion]Ig lambda chain V-IVregion MOL[extracellularregion]Ig lambda chain V-IIregion NEI[extracellularregion]Ig kappa chain V-Iregion Kue[extracellularregion]Ig kappa chain V-Iregion WAT[extracellularregion]C1QA [extracellularregion]C3 beta chain[extracellularregion]N-acetyl-D-glucosamine[plasma membrane]C4B gamma[extracellularregion]Ig heavy chain V-IIIregion TEI[extracellularregion]CD55 [plasmamembrane]Ig kappa chain V-IIIregion IARC/BL41[extracellularregion]Ig heavy chain V-IIIregion TIL[extracellularregion]C3 beta chain[extracellularregion]Ig kappa chain V-Iregion OU[extracellularregion]Ig heavy chain V-IIIregion ZAP[extracellularregion]C4BPA [plasmamembrane]Ig kappa chain V-IIregion FR[extracellularregion]C4B gamma[extracellularregion]Ig heavy chain V-IIIregion BRO[extracellularregion]Ig kappa chain V-Iregion Kue[extracellularregion]C3bIg lambda chainV-VII region MOT[extracellularregion]Ig lambda chain V-IIregion TOG[extracellularregion]C4BPB [plasmamembrane]VTN(20-?)C3fIg kappa chain Vregion EV15[extracellularregion]C4b-binding proteinIg heavy chain V-IIIregion TRO[extracellularregion]C4A gamma[extracellularregion]C3 beta chain[extracellularregion]CD46IGLV2-33(1-?)[extracellularregion]IGHG1(1-330)[extracellularregion]Ig lambda chain V-IIregion NIG-58[extracellularregion]CFB(260-764) [plasmamembrane]CFB(260-764) [plasmamembrane]IGHV(1-?)[extracellularregion]Ig lambda chain V-VIregion WLT[extracellularregion]Ig kappa chain V-Iregion Bi[extracellularregion]Ig heavy chain V-IIIregion WAS[extracellularregion]Ig heavy chain V-IIIregion WAS[extracellularregion]C3c alpha' chainfragment 1 precursor[plasma membrane]Ig kappa chain V-Iregion Hau[extracellularregion]C3 beta chain[extracellularregion]CFI(340-583)[extracellularregion]dNQ-C4B(757-1446)[extracellularregion]C5bC3b alpha'[extracellularregion]VTN(20-?)[extracellularregion]MASP2-1(16-444)[extracellularregion]N-acetylgalactosamine[plasma membrane]C4B gamma[extracellularregion]C8Ig heavy chain V-IIIregion GA[extracellularregion]C3 convertasesC3 beta chain[extracellularregion]C3 beta chain[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]CR1:C4bC3b alpha'[extracellularregion]Ig kappa chain V-IIIregion CLL[extracellularregion]Ig lambda chainV-VII region MOT[extracellularregion]C4B beta[extracellularregion]MASP1(449-699)[extracellularregion]IGLV11-55(1-?)[extracellularregion]CFI(19-335)[extracellularregion]MCP, CR1Ig heavy chain V-IIregion DAW[extracellularregion]C4A beta[extracellularregion]Ig kappa chain V-Iregion OU[extracellularregion]C1R N-terminalfragment[extracellularregion]FCN3 [extracellularregion]IGKVA18(21-?)[extracellularregion]CD46 [plasmamembrane]Ig heavy chain V-IIregion WAH[extracellularregion]Ig kappa chain V-Iregion EU[extracellularregion]Ig kappa chain V-IIregion Cum[extracellularregion]CFI(340-583)IGLC2(?-106)[extracellularregion]Ig kappa chain V-Iregion Mev[extracellularregion]C2a [extracellularregion]Ig heavy chain V-IIIregion POM[extracellularregion]Ig kappa chain V-Iregion Roy[extracellularregion]Ig lambda chain V-VIregion EB4[extracellularregion]IGLC1(1-105)[extracellularregion]MBL/Ficolin:MASPsbound tocarbohydratepatternsMBL2 [extracellularregion]IGHV7-81(1-?)[extracellularregion]IGHG3 [extracellularregion]Ig kappa chain V-IIIregion WOL[extracellularregion]C1R N-terminalfragment[extracellularregion]C4A alpha3[extracellularregion]C8A [extracellularregion]Ig kappa chain V-Iregion Lay[extracellularregion]Ig lambda chain V-IIregion WIN[extracellularregion]DAF:C3 convertasecomplexesIg lambda chain V-Iregion VOR[extracellularregion]CD55 [plasmamembrane]C5 beta[extracellularregion]Ig kappa chain V-Iregion Rei[extracellularregion]Ig lambda chain V-IVregion Kern[extracellularregion]Ig heavy chain V-Iregion WOL[extracellularregion]Ig heavy chain V-IIIregion KOL[extracellularregion]Ig heavy chain V-IIIregion KOL[extracellularregion]C7(22-843)[extracellularregion]CFI(340-583)[extracellularregion]C4B gamma[extracellularregion]IGLV4-3(1-?)[extracellularregion]Ig kappa chain V-IIIregion B6[extracellularregion]IGLV1-36(1-?)[extracellularregion]C6 [extracellularregion]IGLV4-3(1-?)[extracellularregion]C4B gamma[extracellularregion]Ig kappa chain V-Iregion Walker[extracellularregion]Ig lambda chain V-IIregion BUR[extracellularregion]Ig kappa chain V-IIIregion VH[extracellularregion]DAF:C4bC4BPA [plasmamembrane]Ig lambda chain V-Iregion MEM[extracellularregion]Ig heavy chain V-IIIregion BUT[extracellularregion]C4aC4A gamma[extracellularregion]FCN3:MASP2dimer:MASP1 dimerC4B beta[extracellularregion]Ig kappa chain V-Iregion Ni[extracellularregion]C4B gamma[extracellularregion]Ig kappa chain V-Iregion DEE[extracellularregion]C1R C-terminalfragment[extracellularregion]FCN3 [extracellularregion]C4A alpha b[extracellularregion]IGHV(1-?)[extracellularregion]C4B beta[extracellularregion]Ig kappa chain V-IVregion Len[extracellularregion]IGLC3(?-106)[extracellularregion]Ig kappa chain V-Iregion Walker[extracellularregion]D-fucose [plasmamembrane]CFI(19-335)[extracellularregion]Ig heavy chain V-IIregion DAW[extracellularregion]Cell surface:C4b:C2aIg kappa chain V-Iregion Wes[extracellularregion]Ig lambda chain V-Iregion NIG-64[extracellularregion]Ig heavy chain V-Iregion EU[extracellularregion]IGLV3-25(1-?)[extracellularregion]MASP2-1[extracellularregion]Ig lambda chain V-VIregion SUT[extracellularregion]Ig kappa chain V-Iregion Mev[extracellularregion]IGKV4-1(21-?)[extracellularregion]Ig heavy chain V-IIIregion BUT[extracellularregion]C2aCR1 [plasmamembrane]C4b:C2a:C3bIg lambda chain V-IVregion Hil[extracellularregion]Ig heavy chain V-IIIregion NIE[extracellularregion]Ig kappa chain V-Iregion BAN[extracellularregion]Ig kappa chain V-Iregion CAR[extracellularregion]C2a [extracellularregion]C5 beta[extracellularregion]Sialic acid [plasmamembrane]C5b alpha'[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]IGLV3-16(1-?)[extracellularregion]Ig lambda chain V-Iregion BL2[extracellularregion]C4B beta[extracellularregion]Ig lambda chain V-Vregion DEL[extracellularregion]Ig kappa chain V-IIregion TEW[extracellularregion]H2OC3c alpha' chainfragment 2[extracellularregion]Ig heavy chain V-Iregion Mot[extracellularregion]IGKVA18(21-?)[extracellularregion]IGLV3-27(1-?)[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]IGLC3(?-106)[extracellularregion]Ig kappa chain V-Iregion BAN[extracellularregion]Ig heavy chain V-IIregion COR[extracellularregion]11xCbxE-PROS1C2aIg kappa chain V-Iregion Rei[extracellularregion]C5b:C6:C7 complexIGKC(1-106)[extracellularregion]Ig heavy chain V-IIIregion BUR[extracellularregion]Ig kappa chain V-Iregion Hau[extracellularregion]C4B gamma[extracellularregion]Ig kappa chain V-IIIregion POM[extracellularregion]MASP2-1[extracellularregion]MBL/FCN:activatedMASP:carbohydratepatternsIg lambda chain V-Vregion DEL[extracellularregion]C6 [extracellularregion]dNQ-C4B(757-1446)[extracellularregion]C4A beta[extracellularregion]C4B beta[extracellularregion]Ig kappa chain V-IIregion MIL[extracellularregion]Ig heavy chain V-IIIregion GAL[extracellularregion]C4A gamma[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]IGLV7-43(1-?)[extracellularregion]Ig heavy chain V-IIIregion GA[extracellularregion]CFI(19-335)[extracellularregion]Ig lambda chain Vregion 4A[extracellularregion]Ig heavy chain V-IIIregion ZAP[extracellularregion]IGLV2-18(1-?)[extracellularregion]Ig kappa chain V-Iregion Wes[extracellularregion]Ig lambda chain V-IIregion BO[extracellularregion]CFB(26-764)C4B gamma[extracellularregion]dNQ-C4A(757-1446)[extracellularregion]MASP1(20-699)[extracellularregion]Ig lambda chain V-VIregion SUT[extracellularregion]Ig heavy chain V-IIIregion LAY[extracellularregion]Ig kappa chain V-Iregion Daudi[extracellularregion]C3b alpha'[extracellularregion]IGLV4-60(1-?)[extracellularregion]C5 beta[extracellularregion]C3 beta chain[extracellularregion]Ig kappa chain V-IVregion JI[extracellularregion]Ig heavy chain V-Iregion SIE[extracellularregion]C3(H2O):Factor BbIg kappa chain V-Iregion Ka[extracellularregion]IGLC2(?-106)[extracellularregion]Ig heavy chain V-IIIregion GA[extracellularregion]Ig heavy chain V-Iregion ND[extracellularregion]C4B beta[extracellularregion]C3 beta chain[extracellularregion]IGLV5-45(1-?)[extracellularregion]IGLV11-55(1-?)[extracellularregion]Ig kappa chain V-IIIregion B6[extracellularregion]Ig heavy chain V-IIIregion TUR[extracellularregion]Ig kappa chain V-IIregion GM607[extracellularregion]Ig heavy chain V-IIIregion DOB[extracellularregion]C5b alpha'[extracellularregion]C4B gamma[extracellularregion]Ig kappa chain V-IIIregion VH[extracellularregion]C3b alpha'[extracellularregion]Ig kappa chain V-Iregion AG[extracellularregion]5647367076, 877712, 657977864887388611, 47


Description

The complement system is a biochemical cascade, so named because it 'complements' the ability of antibodies to clear pathogens. It is part of the innate immune system. Complement system proteins circulate in the blood as inactive precursors (pro-proteins). When triggered by the presence of microbes, complement proteases cleave complement proteins, initiating a cascade of further cleavages. The end-result of this activation is the activation of the Membrane Attack Complex and cell lysis. The C3 and C5 components also lead to phagocytosis by leukocytes.

There are three branches that lead to activation of the complement system: the classical complement pathway, the alternative complement pathway, and the mannose-binding lectin pathway. Complement proteins are always present in the blood and a small percentage spontaneously activate. Innapropriate activation leads to host cell damage, so the activation process is tightly controlled by several regulatory mechanisms. N.B. Originally the larger fragment of Complement Factor 2 (C2) was designated C2a. However, complement scientists decided that the smaller of all C fragments should be designated with an 'a', the larger with a 'b', changing the nomenclature for C2. Recent literature may use the updated nomenclature and refer to the larger C2 fragment as C2b, and refer to the classical C3 convertase as C4bC2b. Throughout this pathway Reactome adheres to the original convention to agree with the current (Feb 2012) Uniprot names for C2 fragments.Original Pathway at Reactome: http://www.reactome.org/PathwayBrowser/#DB=gk_current&FOCUS_SPECIES_ID=48887&FOCUS_PATHWAY_ID=166658

Try the New WikiPathways

View approved pathways at the new wikipathways.org.

Quality Tags

Ontology Terms

 

Bibliography

View all...
  1. Chen CB, Wallis R.; ''Stoichiometry of complexes between mannose-binding protein and its associated serine proteases. Defining functional units for complement activation.''; PubMed Europe PMC Scholia
  2. Liu Y, Endo Y, Iwaki D, Nakata M, Matsushita M, Wada I, Inoue K, Munakata M, Fujita T.; ''Human M-ficolin is a secretory protein that activates the lectin complement pathway.''; PubMed Europe PMC Scholia
  3. Law SK, Levine RP.; ''Interaction between the third complement protein and cell surface macromolecules.''; PubMed Europe PMC Scholia
  4. Fujita T, Gigli I, Nussenzweig V.; ''Human C4-binding protein. II. Role in proteolysis of C4b by C3b-inactivator.''; PubMed Europe PMC Scholia
  5. Kuraya M, Ming Z, Liu X, Matsushita M, Fujita T.; ''Specific binding of L-ficolin and H-ficolin to apoptotic cells leads to complement activation.''; PubMed Europe PMC Scholia
  6. Tsujimura M, Miyazaki T, Kojima E, Sagara Y, Shiraki H, Okochi K, Maeda Y.; ''Serum concentration of Hakata antigen, a member of the ficolins, is linked with inhibition of Aerococcus viridans growth.''; PubMed Europe PMC Scholia
  7. Hourcade DE, Mitchell L, Kuttner-Kondo LA, Atkinson JP, Medof ME.; ''Decay-accelerating factor (DAF), complement receptor 1 (CR1), and factor H dissociate the complement AP C3 convertase (C3bBb) via sites on the type A domain of Bb.''; PubMed Europe PMC Scholia
  8. Aleshin AE, DiScipio RG, Stec B, Liddington RC.; ''Crystal structure of C5b-6 suggests structural basis for priming assembly of the membrane attack complex.''; PubMed Europe PMC Scholia
  9. Campbell WD, Lazoura E, Okada N, Okada H.; ''Inactivation of C3a and C5a octapeptides by carboxypeptidase R and carboxypeptidase N.''; PubMed Europe PMC Scholia
  10. Daha MR, Fearon DT, Austen KF.; ''C3 requirements for formation of alternative pathway C5 convertase.''; PubMed Europe PMC Scholia
  11. Rawal N, Pangburn MK.; ''Formation of high affinity C5 convertase of the classical pathway of complement.''; PubMed Europe PMC Scholia
  12. Alcorlo M, Tortajada A, Rodríguez de Córdoba S, Llorca O.; ''Structural basis for the stabilization of the complement alternative pathway C3 convertase by properdin.''; PubMed Europe PMC Scholia
  13. Teillet F, Gaboriaud C, Lacroix M, Martin L, Arlaud GJ, Thielens NM.; ''Crystal structure of the CUB1-EGF-CUB2 domain of human MASP-1/3 and identification of its interaction sites with mannan-binding lectin and ficolins.''; PubMed Europe PMC Scholia
  14. Scharfstein J, Ferreira A, Gigli I, Nussenzweig V.; ''Human C4-binding protein. I. Isolation and characterization.''; PubMed Europe PMC Scholia
  15. Krisinger MJ, Goebeler V, Lu Z, Meixner SC, Myles T, Pryzdial EL, Conway EM.; ''Thrombin generates previously unidentified C5 products that support the terminal complement activation pathway.''; PubMed Europe PMC Scholia
  16. DiScipio RG, Davie EW.; ''Characterization of protein S, a gamma-carboxyglutamic acid containing protein from bovine and human plasma.''; PubMed Europe PMC Scholia
  17. Zacho RM, Jensen L, Terp R, Jensenius JC, Thiel S.; ''Studies of the pattern recognition molecule H-ficolin: specificity and purification.''; PubMed Europe PMC Scholia
  18. Ziccardi RJ, Dahlback B, Müller-Eberhard HJ.; ''Characterization of the interaction of human C4b-binding protein with physiological ligands.''; PubMed Europe PMC Scholia
  19. Aoyagi Y, Adderson EE, Rubens CE, Bohnsack JF, Min JG, Matsushita M, Fujita T, Okuwaki Y, Takahashi S.; ''L-Ficolin/mannose-binding lectin-associated serine protease complexes bind to group B streptococci primarily through N-acetylneuraminic acid of capsular polysaccharide and activate the complement pathway.''; PubMed Europe PMC Scholia
  20. Weiler JM, Daha MR, Austen KF, Fearon DT.; ''Control of the amplification convertase of complement by the plasma protein beta1H.''; PubMed Europe PMC Scholia
  21. Kjaer TR, Hansen AG, Sørensen UB, Nielsen O, Thiel S, Jensenius JC.; ''Investigations on the pattern recognition molecule M-ficolin: quantitative aspects of bacterial binding and leukocyte association.''; PubMed Europe PMC Scholia
  22. Lynch NJ, Roscher S, Hartung T, Morath S, Matsushita M, Maennel DN, Kuraya M, Fujita T, Schwaeble WJ.; ''L-ficolin specifically binds to lipoteichoic acid, a cell wall constituent of Gram-positive bacteria, and activates the lectin pathway of complement.''; PubMed Europe PMC Scholia
  23. Law SK, Lichtenberg NA, Holcombe FH, Levine RP.; ''Interaction between the labile binding sites of the fourth (C4) and fifth (C5) human complement proteins and erythrocyte cell membranes.''; PubMed Europe PMC Scholia
  24. Gigli I, Fujita T, Nussenzweig V.; ''Modulation of the classical pathway C3 convertase by plasma proteins C4 binding protein and C3b inactivator.''; PubMed Europe PMC Scholia
  25. Keshi H, Sakamoto T, Kawai T, Ohtani K, Katoh T, Jang SJ, Motomura W, Yoshizaki T, Fukuda M, Koyama S, Fukuzawa J, Fukuoh A, Yoshida I, Suzuki Y, Wakamiya N.; ''Identification and characterization of a novel human collectin CL-K1.''; PubMed Europe PMC Scholia
  26. Masaki T, Matsumoto M, Nakanishi I, Yasuda R, Seya T.; ''Factor I-dependent inactivation of human complement C4b of the classical pathway by C3b/C4b receptor (CR1, CD35) and membrane cofactor protein (MCP, CD46).''; PubMed Europe PMC Scholia
  27. Vorup-Jensen T, Petersen SV, Hansen AG, Poulsen K, Schwaeble W, Sim RB, Reid KB, Davis SJ, Thiel S, Jensenius JC.; ''Distinct pathways of mannan-binding lectin (MBL)- and C1-complex autoactivation revealed by reconstitution of MBL with recombinant MBL-associated serine protease-2.''; PubMed Europe PMC Scholia
  28. Scibek JJ, Plumb ME, Sodetz JM.; ''Binding of human complement C8 to C9: role of the N-terminal modules in the C8 alpha subunit.''; PubMed Europe PMC Scholia
  29. Alcorlo M, Martínez-Barricarte R, Fernández FJ, Rodríguez-Gallego C, Round A, Vega MC, Harris CL, de Cordoba SR, Llorca O.; ''Unique structure of iC3b resolved at a resolution of 24 Å by 3D-electron microscopy.''; PubMed Europe PMC Scholia
  30. Dahlbäck B, Smith CA, Müller-Eberhard HJ.; ''Visualization of human C4b-binding protein and its complexes with vitamin K-dependent protein S and complement protein C4b.''; PubMed Europe PMC Scholia
  31. Goldberger G, Bruns GA, Rits M, Edge MD, Kwiatkowski DJ.; ''Human complement factor I: analysis of cDNA-derived primary structure and assignment of its gene to chromosome 4.''; PubMed Europe PMC Scholia
  32. Honoré C, Rørvig S, Hummelshøj T, Skjoedt MO, Borregaard N, Garred P.; ''Tethering of Ficolin-1 to cell surfaces through recognition of sialic acid by the fibrinogen-like domain.''; PubMed Europe PMC Scholia
  33. Lehto T, Morgan BP, Meri S.; ''Binding of human and rat CD59 to the terminal complement complexes.''; PubMed Europe PMC Scholia
  34. Sim RB, Reboul A, Arlaud GJ, Villiers CL, Colomb MG.; ''Interaction of 125I-labelled complement subcomponents C-1r and C-1s with protease inhibitors in plasma.''; PubMed Europe PMC Scholia
  35. Kalant D, Cain SA, Maslowska M, Sniderman AD, Cianflone K, Monk PN.; ''The chemoattractant receptor-like protein C5L2 binds the C3a des-Arg77/acylation-stimulating protein.''; PubMed Europe PMC Scholia
  36. Davis AE, Harrison RA, Lachmann PJ.; ''Physiologic inactivation of fluid phase C3b: isolation and structural analysis of C3c, C3d,g (alpha 2D), and C3g.''; PubMed Europe PMC Scholia
  37. Kishore U, Ghai R, Greenhough TJ, Shrive AK, Bonifati DM, Gadjeva MG, Waters P, Kojouharova MS, Chakraborty T, Agrawal A.; ''Structural and functional anatomy of the globular domain of complement protein C1q.''; PubMed Europe PMC Scholia
  38. Ziccardi RJ, Cooper NR.; ''Activation of C1r by proteolytic cleavage.''; PubMed Europe PMC Scholia
  39. Teh C, Le Y, Lee SH, Lu J.; ''M-ficolin is expressed on monocytes and is a lectin binding to N-acetyl-D-glucosamine and mediates monocyte adhesion and phagocytosis of Escherichia coli.''; PubMed Europe PMC Scholia
  40. Jokiranta TS, Cheng ZZ, Seeberger H, Jòzsi M, Heinen S, Noris M, Remuzzi G, Ormsby R, Gordon DL, Meri S, Hellwage J, Zipfel PF.; ''Binding of complement factor H to endothelial cells is mediated by the carboxy-terminal glycosaminoglycan binding site.''; PubMed Europe PMC Scholia
  41. Butkowski RJ, Elion J, Downing MR, Mann KG.; ''Primary structure of human prethrombin 2 and alpha-thrombin.''; PubMed Europe PMC Scholia
  42. Fearon DT.; ''Regulation of the amplification C3 convertase of human complement by an inhibitory protein isolated from human erythrocyte membrane.''; PubMed Europe PMC Scholia
  43. Bokisch VA, Müller-Eberhard HJ.; ''Anaphylatoxin inactivator of human plasma: its isolation and characterization as a carboxypeptidase.''; PubMed Europe PMC Scholia
  44. Bhakdi S, Käflein R, Halstensen TS, Hugo F, Preissner KT, Mollnes TE.; ''Complement S-protein (vitronectin) is associated with cytolytic membrane-bound C5b-9 complexes.''; PubMed Europe PMC Scholia
  45. Teillet F, Dublet B, Andrieu JP, Gaboriaud C, Arlaud GJ, Thielens NM.; ''The two major oligomeric forms of human mannan-binding lectin: chemical characterization, carbohydrate-binding properties, and interaction with MBL-associated serine proteases.''; PubMed Europe PMC Scholia
  46. Dahlbäck B, Stenflo J.; ''High molecular weight complex in human plasma between vitamin K-dependent protein S and complement component C4b-binding protein.''; PubMed Europe PMC Scholia
  47. Müller-Eberhard HJ.; ''Molecular organization and function of the complement system.''; PubMed Europe PMC Scholia
  48. Gasque P.; ''Complement: a unique innate immune sensor for danger signals.''; PubMed Europe PMC Scholia
  49. Sheehan M, Morris CA, Pussell BA, Charlesworth JA.; ''Complement inhibition by human vitronectin involves non-heparin binding domains.''; PubMed Europe PMC Scholia
  50. Nagasawa S, Ichihara C, Stroud RM.; ''Cleavage of C4b by C3b inactivator: production of a nicked form of C4b, C4b', as an intermediate cleavage product of C4b by C3b inactivator.''; PubMed Europe PMC Scholia
  51. Kishore U, Reid KB.; ''C1q: structure, function, and receptors.''; PubMed Europe PMC Scholia
  52. Nonaka M, Yoshizaki F.; ''Evolution of the complement system.''; PubMed Europe PMC Scholia
  53. Matsumoto AK, Martin DR, Carter RH, Klickstein LB, Ahearn JM, Fearon DT.; ''Functional dissection of the CD21/CD19/TAPA-1/Leu-13 complex of B lymphocytes.''; PubMed Europe PMC Scholia
  54. Garlatti V, Martin L, Lacroix M, Gout E, Arlaud GJ, Thielens NM, Gaboriaud C.; ''Structural insights into the recognition properties of human ficolins.''; PubMed Europe PMC Scholia
  55. Farries TC, Lachmann PJ, Harrison RA.; ''Analysis of the interactions between properdin, the third component of complement (C3), and its physiological activation products.''; PubMed Europe PMC Scholia
  56. Tschopp J, Chonn A, Hertig S, French LE.; ''Clusterin, the human apolipoprotein and complement inhibitor, binds to complement C7, C8 beta, and the b domain of C9.''; PubMed Europe PMC Scholia
  57. Wu J, Wu YQ, Ricklin D, Janssen BJ, Lambris JD, Gros P.; ''Structure of complement fragment C3b-factor H and implications for host protection by complement regulators.''; PubMed Europe PMC Scholia
  58. Fearon DT, Austen KF.; ''Initiation of C3 cleavage in the alternative complement pathway.''; PubMed Europe PMC Scholia
  59. Wittenborn T, Thiel S, Jensen L, Nielsen HJ, Jensenius JC.; ''Characteristics and biological variations of M-ficolin, a pattern recognition molecule, in plasma.''; PubMed Europe PMC Scholia
  60. Budayova-Spano M, Lacroix M, Thielens NM, Arlaud GJ, Fontecilla-Camps JC, Gaboriaud C.; ''The crystal structure of the zymogen catalytic domain of complement protease C1r reveals that a disruptive mechanical stress is required to trigger activation of the C1 complex.''; PubMed Europe PMC Scholia
  61. Ma YG, Cho MY, Zhao M, Park JW, Matsushita M, Fujita T, Lee BL.; ''Human mannose-binding lectin and L-ficolin function as specific pattern recognition proteins in the lectin activation pathway of complement.''; PubMed Europe PMC Scholia
  62. Matsushita M, Kuraya M, Hamasaki N, Tsujimura M, Shiraki H, Fujita T.; ''Activation of the lectin complement pathway by H-ficolin (Hakata antigen).''; PubMed Europe PMC Scholia
  63. Petersen SV, Thiel S, Jensenius JC.; ''The mannan-binding lectin pathway of complement activation: biology and disease association.''; PubMed Europe PMC Scholia
  64. Preissner KP, Podack ER, Müller-Eberhard HJ.; ''SC5b-7, SC5b-8 and SC5b-9 complexes of complement: ultrastructure and localization of the S-protein (vitronectin) within the macromolecules.''; PubMed Europe PMC Scholia
  65. Ross GD, Lambris JD, Cain JA, Newman SL.; ''Generation of three different fragments of bound C3 with purified factor I or serum. I. Requirements for factor H vs CR1 cofactor activity.''; PubMed Europe PMC Scholia
  66. Huang Y, Fedarovich A, Tomlinson S, Davies C.; ''Crystal structure of CD59: implications for molecular recognition of the complement proteins C8 and C9 in the membrane-attack complex.''; PubMed Europe PMC Scholia
  67. Pangburn MK, Schreiber RD, Müller-Eberhard HJ.; ''Human complement C3b inactivator: isolation, characterization, and demonstration of an absolute requirement for the serum protein beta1H for cleavage of C3b and C4b in solution.''; PubMed Europe PMC Scholia
  68. Lehto T, Meri S.; ''Interactions of soluble CD59 with the terminal complement complexes. CD59 and C9 compete for a nascent epitope on C8.''; PubMed Europe PMC Scholia
  69. Hadders MA, Bubeck D, Roversi P, Hakobyan S, Forneris F, Morgan BP, Pangburn MK, Llorca O, Lea SM, Gros P.; ''Assembly and regulation of the membrane attack complex based on structures of C5b6 and sC5b9.''; PubMed Europe PMC Scholia
  70. Krych-Goldberg M, Hauhart RE, Subramanian VB, Yurcisin BM, Crimmins DL, Hourcade DE, Atkinson JP.; ''Decay accelerating activity of complement receptor type 1 (CD35). Two active sites are required for dissociating C5 convertases.''; PubMed Europe PMC Scholia
  71. Schmidt BZ, Colten HR.; ''Complement: a critical test of its biological importance.''; PubMed Europe PMC Scholia
  72. Schreiber RD, Pangburn MK, Lesavre PH, Müller-Eberhard HJ.; ''Initiation of the alternative pathway of complement: recognition of activators by bound C3b and assembly of the entire pathway from six isolated proteins.''; PubMed Europe PMC Scholia
  73. Kerr MA.; ''The human complement system: assembly of the classical pathway C3 convertase.''; PubMed Europe PMC Scholia
  74. Lesavre PH, Müller-Eberhard HJ.; ''Mechanism of action of factor D of the alternative complement pathway.''; PubMed Europe PMC Scholia
  75. Huang Y, Smith CA, Song H, Morgan BP, Abagyan R, Tomlinson S.; ''Insights into the human CD59 complement binding interface toward engineering new therapeutics.''; PubMed Europe PMC Scholia
  76. Fujita T, Matsushita M, Endo Y.; ''The lectin-complement pathway--its role in innate immunity and evolution.''; PubMed Europe PMC Scholia
  77. Ponnuraj K, Xu Y, Macon K, Moore D, Volanakis JE, Narayana SV.; ''Structural analysis of engineered Bb fragment of complement factor B: insights into the activation mechanism of the alternative pathway C3-convertase.''; PubMed Europe PMC Scholia
  78. Neth O, Jack DL, Dodds AW, Holzel H, Klein NJ, Turner MW.; ''Mannose-binding lectin binds to a range of clinically relevant microorganisms and promotes complement deposition.''; PubMed Europe PMC Scholia
  79. Mold C, Medof ME.; ''C3 nephritic factor protects bound C3bBb from cleavage by factor I and human erythrocytes.''; PubMed Europe PMC Scholia
  80. Podack ER, Tschoop J, Müller-Eberhard HJ.; ''Molecular organization of C9 within the membrane attack complex of complement. Induction of circular C9 polymerization by the C5b-8 assembly.''; PubMed Europe PMC Scholia
  81. Morgan HP, Schmidt CQ, Guariento M, Blaum BS, Gillespie D, Herbert AP, Kavanagh D, Mertens HD, Svergun DI, Johansson CM, Uhrín D, Barlow PN, Hannan JP.; ''Structural basis for engagement by complement factor H of C3b on a self surface.''; PubMed Europe PMC Scholia
  82. Seya T, Atkinson JP.; ''Functional properties of membrane cofactor protein of complement.''; PubMed Europe PMC Scholia
  83. Harris CL, Pettigrew DM, Lea SM, Morgan BP.; ''Decay-accelerating factor must bind both components of the complement alternative pathway C3 convertase to mediate efficient decay.''; PubMed Europe PMC Scholia
  84. Brodbeck WG, Liu D, Sperry J, Mold C, Medof ME.; ''Localization of classical and alternative pathway regulatory activity within the decay-accelerating factor.''; PubMed Europe PMC Scholia
  85. MUELLER-EBERHARD HJ, LEPOW IH.; ''C'1 ESTERASE EFFECT ON ACTIVITY AND PHYSICOCHEMICAL PROPERTIES OF THE FOURTH COMPONENT OF COMPLEMENT.''; PubMed Europe PMC Scholia
  86. Nagasawa S, Stroud RM.; ''Cleavage of C2 by C1s into the antigenically distinct fragments C2a and C2b: demonstration of binding of C2b to C4b.''; PubMed Europe PMC Scholia
  87. Troegeler A, Lugo-Villarino G, Hansen S, Rasolofo V, Henriksen ML, Mori K, Ohtani K, Duval C, Mercier I, Bénard A, Nigou J, Hudrisier D, Wakamiya N, Neyrolles O.; ''Collectin CL-LK Is a Novel Soluble Pattern Recognition Receptor for Mycobacterium tuberculosis.''; PubMed Europe PMC Scholia
  88. Müller-Eberhard HJ, Polley MJ, Calcott MA.; ''Formation and functional significance of a molecular complex derived from the second and the fourth component of human complement.''; PubMed Europe PMC Scholia
  89. Pangburn MK, Schreiber RD, Müller-Eberhard HJ.; ''Formation of the initial C3 convertase of the alternative complement pathway. Acquisition of C3b-like activities by spontaneous hydrolysis of the putative thioester in native C3.''; PubMed Europe PMC Scholia
  90. Gerard NP, Gerard C.; ''The chemotactic receptor for human C5a anaphylatoxin.''; PubMed Europe PMC Scholia
  91. Garlatti V, Martin L, Gout E, Reiser JB, Fujita T, Arlaud GJ, Thielens NM, Gaboriaud C.; ''Structural basis for innate immune sensing by M-ficolin and its control by a pH-dependent conformational switch.''; PubMed Europe PMC Scholia
  92. Weis JJ, Tedder TF, Fearon DT.; ''Identification of a 145,000 Mr membrane protein as the C3d receptor (CR2) of human B lymphocytes.''; PubMed Europe PMC Scholia
  93. Medicus RG, Götze O, Müller-Eberhard HJ.; ''Alternative pathway of complement: recruitment of precursor properdin by the labile C3/C5 convertase and the potentiation of the pathway.''; PubMed Europe PMC Scholia
  94. Barilla-LaBarca ML, Liszewski MK, Lambris JD, Hourcade D, Atkinson JP.; ''Role of membrane cofactor protein (CD46) in regulation of C4b and C3b deposited on cells.''; PubMed Europe PMC Scholia
  95. Becherer JD, Lambris JD.; ''Identification of the C3b receptor-binding domain in third component of complement.''; PubMed Europe PMC Scholia
  96. Matsushita M, Endo Y, Fujita T.; ''Cutting edge: complement-activating complex of ficolin and mannose-binding lectin-associated serine protease.''; PubMed Europe PMC Scholia
  97. Hajela K, Kojima M, Ambrus G, Wong KH, Moffatt BE, Ferluga J, Hajela S, Gál P, Sim RB.; ''The biological functions of MBL-associated serine proteases (MASPs).''; PubMed Europe PMC Scholia
  98. Sepp A, Dodds AW, Anderson MJ, Campbell RD, Willis AC, Law SK.; ''Covalent binding properties of the human complement protein C4 and hydrolysis rate of the internal thioester upon activation.''; PubMed Europe PMC Scholia
  99. Cain SA, Monk PN.; ''The orphan receptor C5L2 has high affinity binding sites for complement fragments C5a and C5a des-Arg(74).''; PubMed Europe PMC Scholia
  100. Kinoshita T, Medof ME, Nussenzweig V.; ''Endogenous association of decay-accelerating factor (DAF) with C4b and C3b on cell membranes.''; PubMed Europe PMC Scholia
  101. Garlatti V, Belloy N, Martin L, Lacroix M, Matsushita M, Endo Y, Fujita T, Fontecilla-Camps JC, Arlaud GJ, Thielens NM, Gaboriaud C.; ''Structural insights into the innate immune recognition specificities of L- and H-ficolins.''; PubMed Europe PMC Scholia
  102. Ziccardi RJ, Cooper NR.; ''Physicochemical and functional characterization of the C1r subunit of the first complement component.''; PubMed Europe PMC Scholia
  103. Pangburn MK, Müller-Eberhard HJ.; ''Kinetic and thermodynamic analysis of the control of C3b by the complement regulatory proteins factors H and I.''; PubMed Europe PMC Scholia
  104. Medof ME, Kinoshita T, Nussenzweig V.; ''Inhibition of complement activation on the surface of cells after incorporation of decay-accelerating factor (DAF) into their membranes.''; PubMed Europe PMC Scholia
  105. Goicoechea de Jorge E, Caesar JJ, Malik TH, Patel M, Colledge M, Johnson S, Hakobyan S, Morgan BP, Harris CL, Pickering MC, Lea SM.; ''Dimerization of complement factor H-related proteins modulates complement activation in vivo.''; PubMed Europe PMC Scholia
  106. Degen SJ, Davie EW.; ''Nucleotide sequence of the gene for human prothrombin.''; PubMed Europe PMC Scholia
  107. Forneris F, Ricklin D, Wu J, Tzekou A, Wallace RS, Lambris JD, Gros P.; ''Structures of C3b in complex with factors B and D give insight into complement convertase formation.''; PubMed Europe PMC Scholia
  108. Smith CA, Pangburn MK, Vogel CW, Müller-Eberhard HJ.; ''Molecular architecture of human properdin, a positive regulator of the alternative pathway of complement.''; PubMed Europe PMC Scholia
  109. Gout E, Garlatti V, Smith DF, Lacroix M, Dumestre-Pérard C, Lunardi T, Martin L, Cesbron JY, Arlaud GJ, Gaboriaud C, Thielens NM.; ''Carbohydrate recognition properties of human ficolins: glycan array screening reveals the sialic acid binding specificity of M-ficolin.''; PubMed Europe PMC Scholia
  110. Honoré C, Rørvig S, Munthe-Fog L, Hummelshøj T, Madsen HO, Borregaard N, Garred P.; ''The innate pattern recognition molecule Ficolin-1 is secreted by monocytes/macrophages and is circulating in human plasma.''; PubMed Europe PMC Scholia
  111. Christmas SE, Christmas SE, de la Mata Espinosa CT, Halliday D, Buxton CA, Cummerson JA, Johnson PM.; ''Levels of expression of complement regulatory proteins CD46, CD55 and CD59 on resting and activated human peripheral blood leucocytes.''; PubMed Europe PMC Scholia
  112. Sim RB, Laich A.; ''Serine proteases of the complement system.''; PubMed Europe PMC Scholia
  113. Ames RS, Li Y, Sarau HM, Nuthulaganti P, Foley JJ, Ellis C, Zeng Z, Su K, Jurewicz AJ, Hertzberg RP, Bergsma DJ, Kumar C.; ''Molecular cloning and characterization of the human anaphylatoxin C3a receptor.''; PubMed Europe PMC Scholia
  114. Dodds AW, Ren XD, Willis AC, Law SK.; ''The reaction mechanism of the internal thioester in the human complement component C4.''; PubMed Europe PMC Scholia
  115. Arlaud GJ, Reboul A, Sim RB, Colomb MG.; ''Interaction of C1-inhibitor with the C1r and C1s subcomponents in human C1.''; PubMed Europe PMC Scholia

History

View all...
CompareRevisionActionTimeUserComment
115062view17:00, 25 January 2021ReactomeTeamReactome version 75
113506view11:58, 2 November 2020ReactomeTeamReactome version 74
112706view16:10, 9 October 2020ReactomeTeamReactome version 73
101621view11:49, 1 November 2018ReactomeTeamreactome version 66
101157view21:35, 31 October 2018ReactomeTeamreactome version 65
100683view20:08, 31 October 2018ReactomeTeamreactome version 64
100233view16:53, 31 October 2018ReactomeTeamreactome version 63
99785view15:18, 31 October 2018ReactomeTeamreactome version 62 (2nd attempt)
99338view12:47, 31 October 2018ReactomeTeamreactome version 62
93740view13:33, 16 August 2017ReactomeTeamreactome version 61
93254view11:18, 9 August 2017ReactomeTeamreactome version 61
86332view09:15, 11 July 2016ReactomeTeamreactome version 56
83391view11:06, 18 November 2015ReactomeTeamVersion54
81582view13:07, 21 August 2015ReactomeTeamVersion53
77042view08:34, 17 July 2014ReactomeTeamFixed remaining interactions
76747view12:11, 16 July 2014ReactomeTeamFixed remaining interactions
76072view10:13, 11 June 2014ReactomeTeamRe-fixing comment source
75782view11:30, 10 June 2014ReactomeTeamReactome 48 Update
75419view10:07, 29 May 2014LifishModified description
75132view14:08, 8 May 2014AnweshaFixing comment source for displaying WikiPathways description
74779view08:52, 30 April 2014ReactomeTeamReactome46
44996view14:41, 6 October 2011MartijnVanIerselOntology Term : 'signaling pathway in the innate immune response' added !
42021view21:50, 4 March 2011MaintBotAutomatic update
39824view05:51, 21 January 2011MaintBotNew pathway

External references

DataNodes

View all...
NameTypeDatabase referenceComment
1,3-beta-D-glucan [plasma membrane]MetaboliteCHEBI:37671 (ChEBI)
11xCbxE-PROS1

[extracellular

region]
ProteinP07225 (Uniprot-TrEMBL)
11xCbxE-PROS1ProteinP07225 (Uniprot-TrEMBL)
Antigen: antibody:

C1 (activated C1R

and C1S) complex
ComplexREACT_8066 (Reactome)
Antigen: antibody:

C1 (activated C1R)

complex
ComplexREACT_8973 (Reactome)
Antigen: antibody: C1 complexComplexREACT_8034 (Reactome)
Bacterial

mannose-based carbohydrate surface

pattern
REACT_8923 (Reactome)
C-reactive protein pentamer:phosphocholine:C1QComplexREACT_25403 (Reactome)
C1QA [extracellular region]ProteinP02745 (Uniprot-TrEMBL)
C1QB(26-251)

[extracellular

region]
ProteinP02746 (Uniprot-TrEMBL)
C1QC [extracellular region]ProteinP02747 (Uniprot-TrEMBL)
C1R C-terminal

fragment [extracellular

region]
ProteinP00736 (Uniprot-TrEMBL)
C1R N-terminal

fragment [extracellular

region]
ProteinP00736 (Uniprot-TrEMBL)
C1R(18-705)

[extracellular

region]
ProteinP00736 (Uniprot-TrEMBL)
C1S C-terminal

fragment [extracellular

region]
ProteinP09871 (Uniprot-TrEMBL)
C1S N-terminal

fragment [extracellular

region]
ProteinP09871 (Uniprot-TrEMBL)
C1S(16-688)

[extracellular

region]
ProteinP09871 (Uniprot-TrEMBL)
C2ProteinP06681 (Uniprot-TrEMBL)
C2a [extracellular region]ProteinP06681 (Uniprot-TrEMBL)
C2aProteinP06681 (Uniprot-TrEMBL)
C2bProteinP06681 (Uniprot-TrEMBL)
C3 alpha chain

[extracellular

region]
ProteinP01024 (Uniprot-TrEMBL)
C3 beta chain

[extracellular

region]
ProteinP01024 (Uniprot-TrEMBL)
C3 beta chain [plasma membrane]ProteinP01024 (Uniprot-TrEMBL)
C3 convertasesREACT_8751 (Reactome)
C3(H2O):Factor BComplexREACT_8649 (Reactome)
C3(H2O):Factor BbComplexREACT_8857 (Reactome)
C3(H2O)ComplexREACT_8268 (Reactome)
C3aProteinP01024 (Uniprot-TrEMBL)
C3b alpha'

[extracellular

region]
ProteinP01024 (Uniprot-TrEMBL)
C3b:Factor

Bb:C3b:Properdin

complex
ComplexREACT_8784 (Reactome)
C3bComplexREACT_8621 (Reactome) Linked by disulphide bond between positions 559 and 816.
C3c alpha' chain

fragment 1 [extracellular

region]
ProteinP01024 (Uniprot-TrEMBL)
C3c alpha' chain

fragment 1 precursor [extracellular

region]
ProteinP01024 (Uniprot-TrEMBL)
C3c alpha' chain

fragment 1 precursor

[plasma membrane]
ProteinP01024 (Uniprot-TrEMBL)
C3c alpha' chain

fragment 2 [extracellular

region]
ProteinP01024 (Uniprot-TrEMBL)
C3c alpha' chain

fragment 2 [plasma

membrane]
ProteinP01024 (Uniprot-TrEMBL)
C3cComplexREACT_164188 (Reactome)
C3dgProteinP01024 (Uniprot-TrEMBL)
C3f [extracellular region]ProteinP01024 (Uniprot-TrEMBL)
C3fProteinP01024 (Uniprot-TrEMBL)
C4 activatorREACT_8154 (Reactome)
C4 alpha

[extracellular

region]
ProteinP0C0L4 (Uniprot-TrEMBL) C4 alpha chain has a thioester bond between Cys 1010 and Gln 1013
C4 binding protein:C4bC2aComplexREACT_120190 (Reactome)
C4 binding protein:protein SComplexREACT_119894 (Reactome)
C4-binding protein:C4bComplexREACT_118966 (Reactome)
C4A alpha b

[extracellular

region]
ProteinP0C0L4 (Uniprot-TrEMBL) C4 alpha chain has a thioester bond between Cys 1010 and Gln 1013
C4A alpha3

[extracellular

region]
ProteinP0C0L4 (Uniprot-TrEMBL)
C4A alpha4 fragment

[extracellular

region]
ProteinP0C0L4 (Uniprot-TrEMBL)
C4A beta

[extracellular

region]
ProteinP0C0L4 (Uniprot-TrEMBL)
C4A gamma

[extracellular

region]
ProteinP0C0L4 (Uniprot-TrEMBL)
C4B alpha

[extracellular

region]
ProteinP0C0L5 (Uniprot-TrEMBL)
C4B alpha chain

fragment b [extracellular

region]
ProteinP0C0L5 (Uniprot-TrEMBL)
C4B alpha3

[extracellular

region]
ProteinP0C0L5 (Uniprot-TrEMBL)
C4B alpha4 fragment

[extracellular

region]
ProteinP0C0L5 (Uniprot-TrEMBL)
C4B beta

[extracellular

region]
ProteinP0C0L5 (Uniprot-TrEMBL)
C4B gamma

[extracellular

region]
ProteinP0C0L5 (Uniprot-TrEMBL)
C4BPA [plasma membrane]ProteinP04003 (Uniprot-TrEMBL)
C4BPB [plasma membrane]ProteinP20851 (Uniprot-TrEMBL)
C4aProteinREACT_25991 (Reactome)
C4b with hydrolysed thioesterComplexREACT_164040 (Reactome)
C4b, C3bComplexREACT_119260 (Reactome)
C4b-binding protein:Factor IComplexREACT_119445 (Reactome)
C4b-binding proteinComplexREACT_120080 (Reactome)
C4b:C2a:C3bComplexREACT_8556 (Reactome)
C4bC2a, C3bBbComplexREACT_119171 (Reactome)
C4c, C3fComplexREACT_119917 (Reactome)
C4cComplexREACT_119729 (Reactome)
C4d, iC3bProteinREACT_119732 (Reactome)
C4dProteinREACT_119059 (Reactome)
C5 alpha

[extracellular

region]
ProteinP01031 (Uniprot-TrEMBL)
C5 beta

[extracellular

region]
ProteinP01031 (Uniprot-TrEMBL)
C5 convertasesREACT_8864 (Reactome)
C5aProteinP01031 (Uniprot-TrEMBL)
C5b alpha'

[extracellular

region]
ProteinP01031 (Uniprot-TrEMBL)
C5b:C6 complexComplexREACT_8500 (Reactome)
C5b:C6:C7 complexComplexREACT_8333 (Reactome)
C5b:C6:C7 complexComplexREACT_8454 (Reactome)
C5b:C6:C7:C8 complexComplexREACT_8352 (Reactome)
C5bComplexREACT_8814 (Reactome) Linked by disulphide bond between positions 559 and 816.
C6 [extracellular region]ProteinP13671 (Uniprot-TrEMBL)
C6ProteinP13671 (Uniprot-TrEMBL)
C7(22-843)

[extracellular

region]
ProteinP10643 (Uniprot-TrEMBL)
C7(22-843)ProteinP10643 (Uniprot-TrEMBL)
C8A [extracellular region]ProteinP07357 (Uniprot-TrEMBL)
C8B [extracellular region]ProteinP07358 (Uniprot-TrEMBL)
C8G [extracellular region]ProteinP07360 (Uniprot-TrEMBL)
C8ComplexREACT_8563 (Reactome)
C9(22-559)

[extracellular

region]
ProteinP02748 (Uniprot-TrEMBL)
C9(22-559)ProteinP02748 (Uniprot-TrEMBL)
CD46 [plasma membrane]ProteinP15529 (Uniprot-TrEMBL)
CD46ProteinP15529 (Uniprot-TrEMBL)
CD55 [plasma membrane]ProteinP08174 (Uniprot-TrEMBL)
CD55ProteinP08174 (Uniprot-TrEMBL)
CD59 [plasma membrane]ProteinP13987 (Uniprot-TrEMBL)
CD59:C5b-C9ComplexREACT_164087 (Reactome)
CD59ProteinP13987 (Uniprot-TrEMBL)
CFB(26-259)ProteinP00751 (Uniprot-TrEMBL)
CFB(26-764)

[extracellular

region]
ProteinP00751 (Uniprot-TrEMBL)
CFB(26-764)ProteinP00751 (Uniprot-TrEMBL)
CFB(260-764)

[extracellular

region]
ProteinP00751 (Uniprot-TrEMBL)
CFB(260-764) [plasma membrane]ProteinP00751 (Uniprot-TrEMBL)
CFB(260-764)ProteinP00751 (Uniprot-TrEMBL)
CFDProteinP00746 (Uniprot-TrEMBL)
CFH [extracellular region]ProteinP08603 (Uniprot-TrEMBL)
CFHProteinP08603 (Uniprot-TrEMBL)
CFI(19-335)

[extracellular

region]
ProteinP05156 (Uniprot-TrEMBL)
CFI(19-335)ProteinP05156 (Uniprot-TrEMBL)
CFI(340-583)

[extracellular

region]
ProteinP05156 (Uniprot-TrEMBL)
CFI(340-583)ProteinP05156 (Uniprot-TrEMBL)
CR1 [plasma membrane]ProteinP17927 (Uniprot-TrEMBL)
CR1:C3bBb, C4bC2a complexesComplexREACT_120030 (Reactome)
CR1:C3bComplexREACT_119014 (Reactome)
CR1:C4bComplexREACT_119535 (Reactome)
CR1:iC3bComplexREACT_164751 (Reactome)
CR1ProteinP17927 (Uniprot-TrEMBL)
CRP(19-224)

[extracellular

region]
ProteinP02741 (Uniprot-TrEMBL)
Ca2+ [extracellular region]MetaboliteCHEBI:29108 (ChEBI)
Ca2+MetaboliteCHEBI:29108 (ChEBI)
Cell

surface:C3b:Factor

Bb:Properdin
ComplexREACT_8531 (Reactome)
Cell

surface:C3b:Factor

Bb
ComplexREACT_8668 (Reactome)
Cell

surface:C3b:Factor B

complex
ComplexREACT_8205 (Reactome)
Cell surface:FH,FHR3:C3bBbComplexREACT_118983 (Reactome)
Cell surface:FH,FHR3:C3bComplexREACT_119386 (Reactome)
Cell surface:C3bComplexREACT_26114 (Reactome)
Cell surface:C4b:C2aComplexREACT_8917 (Reactome)
Cell surface:C4bComplexREACT_25739 (Reactome)
Cell surfaceREACT_26575 (Reactome) This entity is intended to represent any molecule that might be at the outer cell surface of any cell, host or microbial.
Complement Factor 4ComplexREACT_26761 (Reactome)
Complement factor

I:Cell

surface:FH,FHR3:C3b
ComplexREACT_119579 (Reactome)
Complement factor I:Factor H:C3bComplexREACT_119450 (Reactome)
Complement factor 3ComplexREACT_8213 (Reactome) Linked by disulphide bond between positions 559 and 816.
Complement factor 5ComplexREACT_8215 (Reactome)
Complement factor DProteinREACT_161511 (Reactome) This CandidateSet contains sequences identified by William Pearson's analysis of Reactome catalyst entities. Catalyst entity sequences were used to identify analagous sequences that shared overall homology and active site homology. Sequences in this Candidate set were identified in an April 24, 2012 analysis.
Complement factor IComplexREACT_119465 (Reactome)
D-fucose [plasma membrane]MetaboliteCHEBI:28847 (ChEBI)
DAF:C3 convertase complexesComplexREACT_119393 (Reactome)
DAF:C3bComplexREACT_119929 (Reactome)
DAF:C4bComplexREACT_119228 (Reactome)
FCN1 [extracellular region]ProteinO00602 (Uniprot-TrEMBL)
FCN1 ligandMetaboliteREACT_165133 (Reactome)
FCN1:MASP2 dimer:MASP1 dimerComplexREACT_164741 (Reactome)
FCN1:MASPs:Ca2+:FCN1 ligandComplexREACT_165421 (Reactome)
FCN2 [extracellular region]ProteinQ15485 (Uniprot-TrEMBL)
FCN2 ligandMetaboliteREACT_164334 (Reactome)
FCN2:MASP2 dimer:MASP1 dimerComplexREACT_165253 (Reactome)
FCN2:MASPs:Ca2+:FCN2 ligandComplexREACT_164948 (Reactome)
FCN3 [extracellular region]ProteinO75636 (Uniprot-TrEMBL)
FCN3 ligandMetaboliteREACT_165296 (Reactome)
FCN3:MASP2 dimer:MASP1 dimerComplexREACT_165152 (Reactome)
FCN3:MASPs:Ca2+:FCN3 ligandComplexREACT_164302 (Reactome)
FH, FHR-3ProteinREACT_119141 (Reactome)
Factor H:C3bComplexREACT_120113 (Reactome)
Factor H:Host cell surfaceComplexREACT_119254 (Reactome)
Factor I:MCP,

CR1:C4b, C3b

complexes
ComplexREACT_120091 (Reactome)
H2OMetaboliteCHEBI:15377 (ChEBI)
Heparins [plasma membrane]MetaboliteCHEBI:24505 (ChEBI)
Host cell surfaceComplexREACT_119096 (Reactome)
IGHG1(1-330)

[extracellular

region]
ProteinP01857 (Uniprot-TrEMBL)
IGHG2(1-326)

[extracellular

region]
ProteinP01859 (Uniprot-TrEMBL)
IGHG3 [extracellular region]ProteinP01860 (Uniprot-TrEMBL)
IGHG4(1-327)

[extracellular

region]
ProteinP01861 (Uniprot-TrEMBL)
IGHV(1-?)

[extracellular

region]
ProteinA2KUC3 (Uniprot-TrEMBL)
IGHV7-81(1-?)

[extracellular

region]
ProteinQ6PIL0 (Uniprot-TrEMBL)
IGKC(1-106)

[extracellular

region]
ProteinP01834 (Uniprot-TrEMBL)
IGKV1-5(23-?)

[extracellular

region]
ProteinP01602 (Uniprot-TrEMBL)
IGKV4-1(21-?)

[extracellular

region]
ProteinP06312 (Uniprot-TrEMBL)
IGKVA18(21-?)

[extracellular

region]
ProteinA2NJV5 (Uniprot-TrEMBL)
IGLC1(1-105)

[extracellular

region]
ProteinP0CG04 (Uniprot-TrEMBL)
IGLC2(?-106)

[extracellular

region]
ProteinP0CG05 (Uniprot-TrEMBL)
IGLC3(?-106)

[extracellular

region]
ProteinP0CG06 (Uniprot-TrEMBL)
IGLC6(?-106)

[extracellular

region]
ProteinP0CF74 (Uniprot-TrEMBL)
IGLC7(?-106)

[extracellular

region]
ProteinA0M8Q6 (Uniprot-TrEMBL)
IGLV(23-?)

[extracellular

region]
ProteinA2NXD2 (Uniprot-TrEMBL)
IGLV1-36(1-?)

[extracellular

region]
ProteinQ5NV67 (Uniprot-TrEMBL)
IGLV1-40(1-?)

[extracellular

region]
ProteinQ5NV69 (Uniprot-TrEMBL)
IGLV1-44(1-?)

[extracellular

region]
ProteinQ5NV81 (Uniprot-TrEMBL)
IGLV10-54(1-?)

[extracellular

region]
ProteinQ5NV86 (Uniprot-TrEMBL)
IGLV11-55(1-?)

[extracellular

region]
ProteinQ5NV87 (Uniprot-TrEMBL)
IGLV2-11(1-?)

[extracellular

region]
ProteinQ5NV84 (Uniprot-TrEMBL)
IGLV2-18(1-?)

[extracellular

region]
ProteinQ5NV65 (Uniprot-TrEMBL)
IGLV2-23(1-?)

[extracellular

region]
ProteinQ5NV89 (Uniprot-TrEMBL)
IGLV2-33(1-?)

[extracellular

region]
ProteinQ5NV66 (Uniprot-TrEMBL)
IGLV3-12(1-?)

[extracellular

region]
ProteinQ5NV85 (Uniprot-TrEMBL)
IGLV3-16(1-?)

[extracellular

region]
ProteinQ5NV64 (Uniprot-TrEMBL)
IGLV3-22(1-?)

[extracellular

region]
ProteinQ5NV75 (Uniprot-TrEMBL)
IGLV3-25(1-?)

[extracellular

region]
ProteinQ5NV90 (Uniprot-TrEMBL)
IGLV3-27(1-?)

[extracellular

region]
ProteinQ5NV91 (Uniprot-TrEMBL)
IGLV4-3(1-?)

[extracellular

region]
ProteinQ5NV61 (Uniprot-TrEMBL)
IGLV4-60(1-?)

[extracellular

region]
ProteinQ5NV79 (Uniprot-TrEMBL)
IGLV4-69(1-?)

[extracellular

region]
ProteinQ5NV92 (Uniprot-TrEMBL)
IGLV5-37(1-?)

[extracellular

region]
ProteinQ5NV68 (Uniprot-TrEMBL)
IGLV5-45(1-?)

[extracellular

region]
ProteinQ5NV82 (Uniprot-TrEMBL)
IGLV7-43(1-?)

[extracellular

region]
ProteinQ5NV80 (Uniprot-TrEMBL)
IGLV7-46(1-?)

[extracellular

region]
ProteinQ5NV83 (Uniprot-TrEMBL)
IGLV8-61(1-?)

[extracellular

region]
ProteinQ5NV62 (Uniprot-TrEMBL)
Ig heavy chain V-I

region EU [extracellular

region]
ProteinP01742 (Uniprot-TrEMBL)
Ig heavy chain V-I

region HG3 [extracellular

region]
ProteinP01743 (Uniprot-TrEMBL)
Ig heavy chain V-I

region Mot [extracellular

region]
ProteinP06326 (Uniprot-TrEMBL)
Ig heavy chain V-I

region ND [extracellular

region]
ProteinP01744 (Uniprot-TrEMBL)
Ig heavy chain V-I

region SIE [extracellular

region]
ProteinP01761 (Uniprot-TrEMBL)
Ig heavy chain V-I

region WOL [extracellular

region]
ProteinP01760 (Uniprot-TrEMBL)
Ig heavy chain V-II

region ARH-77 [extracellular

region]
ProteinP06331 (Uniprot-TrEMBL)
Ig heavy chain V-II

region COR [extracellular

region]
ProteinP01815 (Uniprot-TrEMBL)
Ig heavy chain V-II

region DAW [extracellular

region]
ProteinP01816 (Uniprot-TrEMBL)
Ig heavy chain V-II

region HE [extracellular

region]
ProteinP01818 (Uniprot-TrEMBL)
Ig heavy chain V-II

region MCE [extracellular

region]
ProteinP01817 (Uniprot-TrEMBL)
Ig heavy chain V-II

region NEWM [extracellular

region]
ProteinP01825 (Uniprot-TrEMBL)
Ig heavy chain V-II

region OU [extracellular

region]
ProteinP01814 (Uniprot-TrEMBL)
Ig heavy chain V-II

region SESS [extracellular

region]
ProteinP04438 (Uniprot-TrEMBL)
Ig heavy chain V-II

region WAH [extracellular

region]
ProteinP01824 (Uniprot-TrEMBL)
Ig heavy chain V-III

region BRO [extracellular

region]
ProteinP01766 (Uniprot-TrEMBL)
Ig heavy chain V-III

region BUR [extracellular

region]
ProteinP01773 (Uniprot-TrEMBL)
Ig heavy chain V-III

region BUT [extracellular

region]
ProteinP01767 (Uniprot-TrEMBL)
Ig heavy chain V-III

region CAM [extracellular

region]
ProteinP01768 (Uniprot-TrEMBL)
Ig heavy chain V-III

region DOB [extracellular

region]
ProteinP01782 (Uniprot-TrEMBL)
Ig heavy chain V-III

region GA [extracellular

region]
ProteinP01769 (Uniprot-TrEMBL)
Ig heavy chain V-III

region GAL [extracellular

region]
ProteinP01781 (Uniprot-TrEMBL)
Ig heavy chain V-III

region HIL [extracellular

region]
ProteinP01771 (Uniprot-TrEMBL)
Ig heavy chain V-III

region JON [extracellular

region]
ProteinP01780 (Uniprot-TrEMBL)
Ig heavy chain V-III

region KOL [extracellular

region]
ProteinP01772 (Uniprot-TrEMBL)
Ig heavy chain V-III

region LAY [extracellular

region]
ProteinP01775 (Uniprot-TrEMBL)
Ig heavy chain V-III

region NIE [extracellular

region]
ProteinP01770 (Uniprot-TrEMBL)
Ig heavy chain V-III

region POM [extracellular

region]
ProteinP01774 (Uniprot-TrEMBL)
Ig heavy chain V-III

region TEI [extracellular

region]
ProteinP01777 (Uniprot-TrEMBL)
Ig heavy chain V-III

region TIL [extracellular

region]
ProteinP01765 (Uniprot-TrEMBL)
Ig heavy chain V-III

region TRO [extracellular

region]
ProteinP01762 (Uniprot-TrEMBL)
Ig heavy chain V-III

region TUR [extracellular

region]
ProteinP01779 (Uniprot-TrEMBL)
Ig heavy chain V-III

region WAS [extracellular

region]
ProteinP01776 (Uniprot-TrEMBL)
Ig heavy chain V-III

region WEA [extracellular

region]
ProteinP01763 (Uniprot-TrEMBL)
Ig heavy chain V-III

region ZAP [extracellular

region]
ProteinP01778 (Uniprot-TrEMBL)
Ig kappa chain V

region EV15 [extracellular

region]
ProteinP06315 (Uniprot-TrEMBL)
Ig kappa chain V-I

region AG [extracellular

region]
ProteinP01593 (Uniprot-TrEMBL)
Ig kappa chain V-I

region AU [extracellular

region]
ProteinP01594 (Uniprot-TrEMBL)
Ig kappa chain V-I

region BAN [extracellular

region]
ProteinP04430 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Bi [extracellular

region]
ProteinP01595 (Uniprot-TrEMBL)
Ig kappa chain V-I

region CAR [extracellular

region]
ProteinP01596 (Uniprot-TrEMBL)
Ig kappa chain V-I

region DEE [extracellular

region]
ProteinP01597 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Daudi [extracellular

region]
ProteinP04432 (Uniprot-TrEMBL)
Ig kappa chain V-I

region EU [extracellular

region]
ProteinP01598 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Gal [extracellular

region]
ProteinP01599 (Uniprot-TrEMBL)
Ig kappa chain V-I

region HK101 [extracellular

region]
ProteinP01601 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Hau [extracellular

region]
ProteinP01600 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Ka [extracellular

region]
ProteinP01603 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Kue [extracellular

region]
ProteinP01604 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Lay [extracellular

region]
ProteinP01605 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Mev [extracellular

region]
ProteinP01612 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Ni [extracellular

region]
ProteinP01613 (Uniprot-TrEMBL)
Ig kappa chain V-I

region OU [extracellular

region]
ProteinP01606 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Rei [extracellular

region]
ProteinP01607 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Roy [extracellular

region]
ProteinP01608 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Scw [extracellular

region]
ProteinP01609 (Uniprot-TrEMBL)
Ig kappa chain V-I

region WAT [extracellular

region]
ProteinP80362 (Uniprot-TrEMBL)
Ig kappa chain V-I

region WEA [extracellular

region]
ProteinP01610 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Walker [extracellular

region]
ProteinP04431 (Uniprot-TrEMBL)
Ig kappa chain V-I

region Wes [extracellular

region]
ProteinP01611 (Uniprot-TrEMBL)
Ig kappa chain V-II

region Cum [extracellular

region]
ProteinP01614 (Uniprot-TrEMBL)
Ig kappa chain V-II

region FR [extracellular

region]
ProteinP01615 (Uniprot-TrEMBL)
Ig kappa chain V-II

region GM607 [extracellular

region]
ProteinP06309 (Uniprot-TrEMBL)
Ig kappa chain V-II

region MIL [extracellular

region]
ProteinP01616 (Uniprot-TrEMBL)
Ig kappa chain V-II

region RPMI 6410 [extracellular

region]
ProteinP06310 (Uniprot-TrEMBL)
Ig kappa chain V-II

region TEW [extracellular

region]
ProteinP01617 (Uniprot-TrEMBL)
Ig kappa chain V-III

region B6 [extracellular

region]
ProteinP01619 (Uniprot-TrEMBL)
Ig kappa chain V-III

region CLL [extracellular

region]
ProteinP04207 (Uniprot-TrEMBL)
Ig kappa chain V-III

region GOL [extracellular

region]
ProteinP04206 (Uniprot-TrEMBL)
Ig kappa chain V-III

region HAH [extracellular

region]
ProteinP18135 (Uniprot-TrEMBL)
Ig kappa chain V-III

region HIC [extracellular

region]
ProteinP18136 (Uniprot-TrEMBL)
Ig kappa chain V-III

region IARC/BL41 [extracellular

region]
ProteinP06311 (Uniprot-TrEMBL)
Ig kappa chain V-III

region NG9 [extracellular

region]
ProteinP01621 (Uniprot-TrEMBL)
Ig kappa chain V-III

region POM [extracellular

region]
ProteinP01624 (Uniprot-TrEMBL)
Ig kappa chain V-III

region SIE [extracellular

region]
ProteinP01620 (Uniprot-TrEMBL)
Ig kappa chain V-III

region Ti [extracellular

region]
ProteinP01622 (Uniprot-TrEMBL)
Ig kappa chain V-III

region VG [extracellular

region]
ProteinP04433 (Uniprot-TrEMBL)
Ig kappa chain V-III

region VH [extracellular

region]
ProteinP04434 (Uniprot-TrEMBL)
Ig kappa chain V-III

region WOL [extracellular

region]
ProteinP01623 (Uniprot-TrEMBL)
Ig kappa chain V-IV

region B17 [extracellular

region]
ProteinP06314 (Uniprot-TrEMBL)
Ig kappa chain V-IV

region JI [extracellular

region]
ProteinP06313 (Uniprot-TrEMBL)
Ig kappa chain V-IV

region Len [extracellular

region]
ProteinP01625 (Uniprot-TrEMBL)
Ig kappa chain V-IV

region STH [extracellular

region]
ProteinP83593 (Uniprot-TrEMBL)
Ig lambda chain

V-III region LOI [extracellular

region]
ProteinP80748 (Uniprot-TrEMBL)
Ig lambda chain

V-III region SH [extracellular

region]
ProteinP01714 (Uniprot-TrEMBL)
Ig lambda chain

V-VII region MOT [extracellular

region]
ProteinP01720 (Uniprot-TrEMBL)
Ig lambda chain V

region 4A [extracellular

region]
ProteinP04211 (Uniprot-TrEMBL)
Ig lambda chain V-I

region BL2 [extracellular

region]
ProteinP06316 (Uniprot-TrEMBL)
Ig lambda chain V-I

region EPS [extracellular

region]
ProteinP06888 (Uniprot-TrEMBL)
Ig lambda chain V-I

region HA [extracellular

region]
ProteinP01700 (Uniprot-TrEMBL)
Ig lambda chain V-I

region MEM [extracellular

region]
ProteinP06887 (Uniprot-TrEMBL)
Ig lambda chain V-I

region NEW [extracellular

region]
ProteinP01701 (Uniprot-TrEMBL)
Ig lambda chain V-I

region NEWM [extracellular

region]
ProteinP01703 (Uniprot-TrEMBL)
Ig lambda chain V-I

region NIG-64 [extracellular

region]
ProteinP01702 (Uniprot-TrEMBL)
Ig lambda chain V-I

region VOR [extracellular

region]
ProteinP01699 (Uniprot-TrEMBL)
Ig lambda chain V-I

region WAH [extracellular

region]
ProteinP04208 (Uniprot-TrEMBL)
Ig lambda chain V-II

region BO [extracellular

region]
ProteinP01710 (Uniprot-TrEMBL)
Ig lambda chain V-II

region BOH [extracellular

region]
ProteinP01706 (Uniprot-TrEMBL)
Ig lambda chain V-II

region BUR [extracellular

region]
ProteinP01708 (Uniprot-TrEMBL)
Ig lambda chain V-II

region MGC [extracellular

region]
ProteinP01709 (Uniprot-TrEMBL)
Ig lambda chain V-II

region NEI [extracellular

region]
ProteinP01705 (Uniprot-TrEMBL)
Ig lambda chain V-II

region NIG-58 [extracellular

region]
ProteinP01713 (Uniprot-TrEMBL)
Ig lambda chain V-II

region NIG-84 [extracellular

region]
ProteinP04209 (Uniprot-TrEMBL)
Ig lambda chain V-II

region TOG [extracellular

region]
ProteinP01704 (Uniprot-TrEMBL)
Ig lambda chain V-II

region TRO [extracellular

region]
ProteinP01707 (Uniprot-TrEMBL)
Ig lambda chain V-II

region VIL [extracellular

region]
ProteinP01711 (Uniprot-TrEMBL)
Ig lambda chain V-II

region WIN [extracellular

region]
ProteinP01712 (Uniprot-TrEMBL)
Ig lambda chain V-IV

region Bau [extracellular

region]
ProteinP01715 (Uniprot-TrEMBL)
Ig lambda chain V-IV

region Hil [extracellular

region]
ProteinP01717 (Uniprot-TrEMBL)
Ig lambda chain V-IV

region Kern [extracellular

region]
ProteinP01718 (Uniprot-TrEMBL)
Ig lambda chain V-IV

region MOL [extracellular

region]
ProteinP06889 (Uniprot-TrEMBL)
Ig lambda chain V-IV

region X [extracellular

region]
ProteinP01716 (Uniprot-TrEMBL)
Ig lambda chain V-V

region DEL [extracellular

region]
ProteinP01719 (Uniprot-TrEMBL)
Ig lambda chain V-VI

region AR [extracellular

region]
ProteinP01721 (Uniprot-TrEMBL)
Ig lambda chain V-VI

region EB4 [extracellular

region]
ProteinP06319 (Uniprot-TrEMBL)
Ig lambda chain V-VI

region NIG-48 [extracellular

region]
ProteinP01722 (Uniprot-TrEMBL)
Ig lambda chain V-VI

region SUT [extracellular

region]
ProteinP06317 (Uniprot-TrEMBL)
Ig lambda chain V-VI

region WLT [extracellular

region]
ProteinP06318 (Uniprot-TrEMBL)
IgH heavy chain

V-III region VH26 precursor [extracellular

region]
ProteinP01764 (Uniprot-TrEMBL)
Lipoteichoic acid [plasma membrane]MetaboliteCHEBI:28640 (ChEBI)
MASP1(20-448)

[extracellular

region]
ProteinP48740 (Uniprot-TrEMBL)
MASP1(20-699)

[extracellular

region]
ProteinP48740 (Uniprot-TrEMBL)
MASP1(449-699)

[extracellular

region]
ProteinP48740 (Uniprot-TrEMBL)
MASP2-1

[extracellular

region]
ProteinO00187-1 (Uniprot-TrEMBL)
MASP2-1(16-444)

[extracellular

region]
ProteinO00187-1 (Uniprot-TrEMBL)
MASP2-1(445-686)

[extracellular

region]
ProteinO00187-1 (Uniprot-TrEMBL)
MBL bound to

mannose-based carbohydrates on

bacterial surfaces
ComplexREACT_8711 (Reactome)
MBL-II:MASP-2

dimer:MASP-1 dimer

complex
ComplexREACT_8380 (Reactome)
MBL/FCN:activated

MASP:carbohydrate

patterns
ComplexREACT_165602 (Reactome)
MBL/Ficolin:MASPs

bound to carbohydrate

patterns
ComplexREACT_165125 (Reactome)
MBL2 [extracellular region]ProteinP11226 (Uniprot-TrEMBL)
MBL:activated

MASPs:mannose-based

carbohydrates
ComplexREACT_8515 (Reactome)
MCP, CR1:C4b:C3b complexesComplexREACT_120251 (Reactome)
MCP, CR1ProteinREACT_119720 (Reactome) CR1 and MCP are widely distributed cell surface molecules that bind C4b and C3b, and act as cofactors for Complement factor I, thereby regulating the classical and alternative C3 convertases.
MCP:C3bComplexREACT_119903 (Reactome)
MCP:C4bComplexREACT_119237 (Reactome)
Membrane Attack ComplexComplexREACT_8325 (Reactome)
N-acetyl-D-glucosamine [plasma membrane]MetaboliteCHEBI:28009 (ChEBI)
N-acetylgalactosamine [plasma membrane]MetaboliteCHEBI:40356 (ChEBI)
PCho [plasma membrane]MetaboliteCHEBI:36700 (ChEBI)
Properdin oligomerREACT_8730 (Reactome)
Sialic acid [plasma membrane]MetaboliteCHEBI:28879 (ChEBI)
VTN(20-?)

[extracellular

region]
ProteinP04004 (Uniprot-TrEMBL)
VTN(20-?)ProteinP04004 (Uniprot-TrEMBL)
VTN:C5b:C6:C7:C8:C9ComplexREACT_164606 (Reactome)
VTN:C5b:C6:C7ComplexREACT_165289 (Reactome)
dNQ-C3(672-1663)

[extracellular

region]
ProteinP01024 (Uniprot-TrEMBL)
dNQ-C4A(757-1446)

[extracellular

region]
ProteinP0C0L4 (Uniprot-TrEMBL)
dNQ-C4B(757-1446)

[extracellular

region]
ProteinP0C0L5 (Uniprot-TrEMBL)
iC3bComplexREACT_119218 (Reactome)
iC3bComplexREACT_120169 (Reactome)
thioester-C1010-Q1013-C4bComplexREACT_26471 (Reactome)

Annotated Interactions

View all...
SourceTargetTypeDatabase referenceComment
11xCbxE-PROS1REACT_118836 (Reactome)
Antigen: antibody:

C1 (activated C1R

and C1S) complex
ArrowREACT_7977 (Reactome)
Antigen: antibody:

C1 (activated C1R)

complex
ArrowREACT_7978 (Reactome)
Antigen: antibody:

C1 (activated C1R)

complex
REACT_7977 (Reactome)
Antigen: antibody:

C1 (activated C1R)

complex
mim-catalysisREACT_7977 (Reactome)
Antigen: antibody: C1 complexREACT_7978 (Reactome)
Antigen: antibody: C1 complexmim-catalysisREACT_7978 (Reactome)
Bacterial

mannose-based carbohydrate surface

pattern
REACT_7983 (Reactome)
C-reactive protein pentamer:phosphocholine:C1QArrowREACT_7978 (Reactome)
C2REACT_7959 (Reactome)
C2aArrowREACT_118584 (Reactome)
C2aArrowREACT_118641 (Reactome)
C2aArrowREACT_118692 (Reactome)
C2aArrowREACT_118738 (Reactome)
C2aArrowREACT_7959 (Reactome)
C2aREACT_8014 (Reactome)
C2bArrowREACT_7959 (Reactome)
C3 convertasesREACT_118641 (Reactome)
C3 convertasesmim-catalysisREACT_7990 (Reactome)
C3(H2O):Factor BArrowREACT_8013 (Reactome)
C3(H2O):Factor BREACT_7981 (Reactome)
C3(H2O):Factor BbArrowREACT_7981 (Reactome)
C3(H2O):Factor Bbmim-catalysisREACT_7948 (Reactome)
C3(H2O)ArrowREACT_118641 (Reactome)
C3(H2O)ArrowREACT_8007 (Reactome)
C3(H2O)REACT_8013 (Reactome)
C3aArrowREACT_7948 (Reactome)
C3aArrowREACT_7986 (Reactome)
C3aArrowREACT_7990 (Reactome)
C3b:Factor

Bb:C3b:Properdin

complex
ArrowREACT_7986 (Reactome)
C3bArrowREACT_118641 (Reactome)
C3bArrowREACT_7948 (Reactome)
C3bArrowREACT_7990 (Reactome)
C3bREACT_118712 (Reactome)
C3bREACT_25075 (Reactome)
C3cArrowREACT_163860 (Reactome)
C3dgArrowREACT_163860 (Reactome)
C3fArrowREACT_118650 (Reactome)
C3fArrowREACT_118841 (Reactome)
C4 activatormim-catalysisREACT_7959 (Reactome)
C4 activatormim-catalysisREACT_8002 (Reactome)
C4 binding protein:C4bC2aArrowREACT_118752 (Reactome)
C4 binding protein:C4bC2aREACT_118738 (Reactome)
C4 binding protein:protein SArrowREACT_118836 (Reactome)
C4-binding protein:C4bArrowREACT_118738 (Reactome)
C4-binding protein:C4bArrowREACT_118763 (Reactome)
C4-binding protein:C4bREACT_118647 (Reactome)
C4aArrowREACT_8002 (Reactome)
C4b with hydrolysed thioesterArrowREACT_163768 (Reactome)
C4b, C3bREACT_118575 (Reactome)
C4b-binding protein:Factor IArrowREACT_118647 (Reactome)
C4b-binding protein:Factor IREACT_118719 (Reactome)
C4b-binding proteinArrowREACT_118719 (Reactome)
C4b-binding proteinREACT_118752 (Reactome)
C4b-binding proteinREACT_118763 (Reactome)
C4b-binding proteinREACT_118836 (Reactome)
C4b:C2a:C3bArrowREACT_8022 (Reactome)
C4bC2a, C3bBbREACT_118580 (Reactome)
C4bC2a, C3bBbREACT_118782 (Reactome)
C4c, C3fArrowREACT_118673 (Reactome)
C4cArrowREACT_118719 (Reactome)
C4d, iC3bArrowREACT_118673 (Reactome)
C4dArrowREACT_118719 (Reactome)
C5 convertasesmim-catalysisREACT_7989 (Reactome)
C5aArrowREACT_7989 (Reactome)
C5b:C6 complexArrowREACT_7976 (Reactome)
C5b:C6 complexREACT_7950 (Reactome)
C5b:C6:C7 complexArrowREACT_7950 (Reactome)
C5b:C6:C7 complexArrowREACT_7982 (Reactome)
C5b:C6:C7 complexREACT_163759 (Reactome)
C5b:C6:C7 complexREACT_7946 (Reactome)
C5b:C6:C7 complexREACT_7982 (Reactome)
C5b:C6:C7:C8 complexArrowREACT_7946 (Reactome)
C5b:C6:C7:C8 complexREACT_163829 (Reactome)
C5b:C6:C7:C8 complexREACT_7988 (Reactome)
C5bArrowREACT_7989 (Reactome)
C5bREACT_7976 (Reactome)
C6REACT_7976 (Reactome)
C7(22-843)REACT_7950 (Reactome)
C8REACT_163870 (Reactome)
C8REACT_7946 (Reactome)
C9(22-559)REACT_163829 (Reactome)
C9(22-559)REACT_163870 (Reactome)
C9(22-559)REACT_7988 (Reactome)
CD46REACT_118575 (Reactome)
CD55REACT_118782 (Reactome)
CD59:C5b-C9ArrowREACT_163829 (Reactome)
CD59REACT_163829 (Reactome)
CFB(26-259)ArrowREACT_7981 (Reactome)
CFB(26-259)ArrowREACT_8026 (Reactome)
CFB(26-764)REACT_7966 (Reactome)
CFB(26-764)REACT_8013 (Reactome)
CFB(260-764)ArrowREACT_118584 (Reactome)
CFB(260-764)ArrowREACT_118641 (Reactome)
CFB(260-764)ArrowREACT_118692 (Reactome)
CFB(260-764)ArrowREACT_118727 (Reactome)
CFHArrowREACT_118650 (Reactome)
CFHREACT_118604 (Reactome)
CFHREACT_118712 (Reactome)
CFI(19-335)REACT_118674 (Reactome)
CFI(340-583)REACT_118674 (Reactome)
CR1:C3bArrowREACT_118692 (Reactome)
CR1:C3bBb, C4bC2a complexesArrowREACT_118580 (Reactome)
CR1:C3bBb, C4bC2a complexesREACT_118692 (Reactome)
CR1:C4bArrowREACT_118692 (Reactome)
CR1:iC3bREACT_163860 (Reactome)
CR1ArrowREACT_163860 (Reactome)
CR1REACT_118580 (Reactome)
Ca2+REACT_163715 (Reactome)
Ca2+REACT_163747 (Reactome)
Ca2+REACT_163758 (Reactome)
Ca2+REACT_7983 (Reactome)
Cell

surface:C3b:Factor

Bb:Properdin
ArrowREACT_8018 (Reactome)
Cell

surface:C3b:Factor

Bb:Properdin
REACT_7986 (Reactome)
Cell

surface:C3b:Factor

Bb:Properdin
mim-catalysisREACT_7986 (Reactome)
Cell

surface:C3b:Factor

Bb
ArrowREACT_8026 (Reactome)
Cell

surface:C3b:Factor

Bb
REACT_118710 (Reactome)
Cell

surface:C3b:Factor

Bb
REACT_8018 (Reactome)
Cell

surface:C3b:Factor B

complex
ArrowREACT_7966 (Reactome)
Cell

surface:C3b:Factor B

complex
REACT_8026 (Reactome)
Cell surface:FH,FHR3:C3bArrowREACT_118727 (Reactome)
Cell surface:FH,FHR3:C3bArrowREACT_118815 (Reactome)
Cell surface:FH,FHR3:C3bBbArrowREACT_118710 (Reactome)
Cell surface:FH,FHR3:C3bBbREACT_118727 (Reactome)
Cell surface:FH,FHR3:C3bREACT_118844 (Reactome)
Cell surface:C3bArrowREACT_25075 (Reactome)
Cell surface:C3bREACT_118815 (Reactome)
Cell surface:C3bREACT_7966 (Reactome)
Cell surface:C3bREACT_8022 (Reactome)
Cell surface:C4b:C2aArrowREACT_118641 (Reactome)
Cell surface:C4b:C2aArrowREACT_8014 (Reactome)
Cell surface:C4b:C2aREACT_118752 (Reactome)
Cell surface:C4b:C2aREACT_8022 (Reactome)
Cell surface:C4bArrowREACT_118641 (Reactome)
Cell surface:C4bArrowREACT_25166 (Reactome)
Cell surface:C4bREACT_8014 (Reactome)
Cell surfaceREACT_25075 (Reactome)
Cell surfaceREACT_25166 (Reactome)
Complement Factor 4REACT_8002 (Reactome)
Complement factor

I:Cell

surface:FH,FHR3:C3b
ArrowREACT_118844 (Reactome)
Complement factor

I:Cell

surface:FH,FHR3:C3b
REACT_118841 (Reactome)
Complement factor

I:Cell

surface:FH,FHR3:C3b
mim-catalysisREACT_118841 (Reactome)
Complement factor I:Factor H:C3bArrowREACT_118583 (Reactome)
Complement factor I:Factor H:C3bREACT_118650 (Reactome)
Complement factor I:Factor H:C3bmim-catalysisREACT_118650 (Reactome)
Complement factor 3REACT_7948 (Reactome)
Complement factor 3REACT_7986 (Reactome)
Complement factor 3REACT_7990 (Reactome)
Complement factor 3REACT_8007 (Reactome)
Complement factor 5REACT_7989 (Reactome)
Complement factor Dmim-catalysisREACT_7981 (Reactome)
Complement factor Dmim-catalysisREACT_8026 (Reactome)
Complement factor IArrowREACT_118650 (Reactome)
Complement factor IArrowREACT_118673 (Reactome)
Complement factor IArrowREACT_118674 (Reactome)
Complement factor IArrowREACT_118719 (Reactome)
Complement factor IArrowREACT_118841 (Reactome)
Complement factor IREACT_118583 (Reactome)
Complement factor IREACT_118631 (Reactome)
Complement factor IREACT_118647 (Reactome)
Complement factor IREACT_118844 (Reactome)
DAF:C3 convertase complexesArrowREACT_118782 (Reactome)
DAF:C3 convertase complexesREACT_118584 (Reactome)
DAF:C3bArrowREACT_118584 (Reactome)
DAF:C4bArrowREACT_118584 (Reactome)
FCN1 ligandREACT_163715 (Reactome)
FCN1:MASP2 dimer:MASP1 dimerREACT_163715 (Reactome)
FCN1:MASPs:Ca2+:FCN1 ligandArrowREACT_163715 (Reactome)
FCN2 ligandREACT_163747 (Reactome)
FCN2:MASP2 dimer:MASP1 dimerREACT_163747 (Reactome)
FCN2:MASPs:Ca2+:FCN2 ligandArrowREACT_163747 (Reactome)
FCN3 ligandREACT_163758 (Reactome)
FCN3:MASP2 dimer:MASP1 dimerREACT_163758 (Reactome)
FCN3:MASPs:Ca2+:FCN3 ligandArrowREACT_163758 (Reactome)
FH, FHR-3ArrowREACT_118841 (Reactome)
FH, FHR-3REACT_118710 (Reactome)
FH, FHR-3REACT_118815 (Reactome)
Factor H:C3bArrowREACT_118712 (Reactome)
Factor H:C3bREACT_118583 (Reactome)
Factor H:Host cell surfaceArrowREACT_118604 (Reactome)
Factor H:Host cell surfaceArrowREACT_118710 (Reactome)
Factor H:Host cell surfaceArrowREACT_118815 (Reactome)
Factor I:MCP,

CR1:C4b, C3b

complexes
ArrowREACT_118631 (Reactome)
Factor I:MCP,

CR1:C4b, C3b

complexes
REACT_118673 (Reactome)
Factor I:MCP,

CR1:C4b, C3b

complexes
mim-catalysisREACT_118673 (Reactome)
H2OREACT_163768 (Reactome)
H2OREACT_8007 (Reactome)
Host cell surfaceREACT_118604 (Reactome)
MBL bound to

mannose-based carbohydrates on

bacterial surfaces
ArrowREACT_7983 (Reactome)
MBL-II:MASP-2

dimer:MASP-1 dimer

complex
REACT_7983 (Reactome)
MBL/FCN:activated

MASP:carbohydrate

patterns
ArrowREACT_7965 (Reactome)
MBL/Ficolin:MASPs

bound to carbohydrate

patterns
REACT_7965 (Reactome)
MCP, CR1:C4b:C3b complexesREACT_118631 (Reactome)
MCP, CR1ArrowREACT_118673 (Reactome)
MCP:C3bArrowREACT_118575 (Reactome)
MCP:C4bArrowREACT_118575 (Reactome)
Membrane Attack ComplexArrowREACT_7988 (Reactome)
Properdin oligomerArrowREACT_118641 (Reactome)
Properdin oligomerREACT_8018 (Reactome)
REACT_118575 (Reactome) Membrane cofactor protein (MCP; CD46) is a widely distributed C3b/C4b-binding cell surface glycoprotein which is a cofactor for Complement factor I.
REACT_118580 (Reactome) Complement Receptor 1 (CR1) is a widely distributed cell surface protein that is a decay accelerating factor for the conventional (C4bC2a) and alternative (C3bBb) C3 convertases (Coico & Sunshine 2009).
REACT_118583 (Reactome) Complement factor I binds the factor H:C3b complex.
REACT_118584 (Reactome) Decay accelerating factor (DAF, CD55) is a widely distributed membrane protein. It accelerates the dissociation of C3bBb and C4C2a, thereby inhibiting the amplification of complement. DAF can bind C3b and Bb but must bind both for efficient decay acceleration. The regulatory function of DAF is believed to be inhibition of activated C3 convertase enzymes rather than binding of inactive proenzymes (Harris et al. 2007).
REACT_118604 (Reactome) Factor H preferentially binds to host cells and surfaces that have negatively charged cell surface polyanions such as heparin and sialic acid commonly found on host cells (Kazatchkine et al. 1979, Meri & Pangburn 1990). This mediates protection of plasma-exposed host structures.
REACT_118631 (Reactome) Membrane cofactor protein (MCP) and Complement Receptor 1 (CR1) act as cofactors for the protease activity of complement factor I which binds MCP or CR1 complexes with C3b or C4b, inactivating C3b/C4b.
REACT_118641 (Reactome) C3b:Bb is naturally labile with a half-life of ~90 s. unless bound to properdin on the cell surface (Medicus et al. 1976). C4bC2a is also unstable, lasting at best a few minutes (Kerr et al. 1980). Decay is associated with the release of the Bb or C2a fragments respectively into the fluid phase. The liberated C3b/C4b is able to re-bind Bb/C2a if Factor B/C2 are present.
REACT_118647 (Reactome) C4b-binding protein is a cofactor for Complement Factor I, allowing it to bind and thereby mediating C4b proteolysis.
REACT_118650 (Reactome) Complement factor I cleaves the alpha chain of C3b at two positions, generating inactivated C3b (iC3b) and a small fragment C3f which is released. The majority of the alpha chain is retained as two fragments which are tethered by disulphide bonds. iC3b is proteolytically inactive.
REACT_118673 (Reactome) Factor I cleaves the truncated alpha (a') chain of C4b between Arg-1336 and Asn-1337 and then again between Arg-956 and Thr-957, producing a 16 kDa fragment known as alpha4, derived from the C terminus of the a' chain, followed by a 27 kDa alpha3 fragment. The remaining alpha 2 (C4d) fragment stays covalently bound to the cell membrane while the complex of disulfide-linked alpha3, alpha4, beta chain and gamma chain are released (C4c) into the fluid phase (Fujita et al. 1978).
REACT_118674 (Reactome) Complement factor I (CFI) is a complex of one heavy and one light chain, both cleaved from the same precursor peptide. It inactivates complement subcomponents C3b, iC3b and C4b by proteolytic cleavage of the alpha chains of C4b and C3b in the presence of cofactors such as Factor H, C4b binding protein, Complement receptor 1 (CR1) or MCP (CD46).
REACT_118692 (Reactome) Complement Receptor 1 (CR1) displaces the activated enzyme components Bb and C2a from the conventional and alternative C3 convertases C4bC2a and C3bBb, respectivley.
REACT_118710 (Reactome) Factor H (FH) binds to C3bBb, leading to displacement of Bb. Complement factor H-related protein 3 (FHR-3) has also been reported to bind C3Bb leading to inhibition of C3Bb C3 convertase activity (Fritsche et al. 2010). FH also acts as a cofactor for the factor I-mediated proteolytic inactivation of C3b to iC3b.
REACT_118712 (Reactome) Factor H (FH) regulates the alternative pathway C3 convertase C3bBb and its C3b component both in plasma and at host cell surfaces. FH binds to plasma C3b, making it unavailable, and acts as a cofactor for the factor I-mediated proteolytic inactivation of C3b to iC3b.
REACT_118719 (Reactome) C4b-binding protein is a cofactor in Factor I mediated C4b proteolysis. C4b is cleaved, releasing C4c, leaving C4d bound to the cell surface.
REACT_118727 (Reactome) Factor H greatly accelerates the displacement (decay) of Complement factor Bb from C3b.
REACT_118738 (Reactome) C4 binding protein accelerates the decay of C4bC2a in a dose-dependent fashion. The mechanism of this is poorly understood, but is distinct from Factor I mediated degradation of C4b and believed to represent the displacement of C2a from specific binding sites on C4b (Gigli et al. 1979).
REACT_118752 (Reactome) C4 binding protein accelerates the decay of C4bC2a in a dose-dependent fashion, without causing degradation of C4b, and is presumed to bind to the convertase to mediate this effect.
REACT_118763 (Reactome) The most abundant form of C4b-binding protein (C4BP) consists of seven alpha-chains (70kDa) and one beta-chain (45kDa) all linked by disulphide bonds to form a native protein with a molecular weight of 570kDa (Hilarp et al. 1989). Each alpha chain can bind C4b; it is not known whether full occupancy is necessary for subsequent events. The beta chain binds and inactivates Protein S, a component of the coagulation system. C4BP down-regulates complement activity in several ways: It binds to C4b thus inhibiting the formation of the classical pathway C3 convertase C4bC2a; it acts as a decay accelerating factor for existing convertases, probably by promoting dissociation of C2a; it is a cofactor in Factor I mediated C4b proteolysis.
REACT_118782 (Reactome) Decay-accelerating-factor (DAF, CD55) is a membrane- bound complement regulatory protein that inhibits autologous complement cascade activation. It is expressed on all cells that are in close contact with serum complement proteins, but also on cells outside the vascular space and on tumour cells. DAF binds to C3bBb and C4bC2a on cell surfaces, accelerating their dissociation and thereby inhibiting the amplification of complement. DAF can bind C3b and Bb, and must bind both for efficient decay acceleration. Although it can bind the inactive proenzymes C3b and C4b, the regulatory function of DAF is believed to be inhibition of activated C3 convertase enzymes (Harris et al. 2007).
REACT_118815 (Reactome) Factor H (FH) regulates the alternative pathway C3 convertase C3bBb and its C3b component both in plasma and at host cell surfaces. FH binds to membrane-associated C3b, competing with Factor B and thereby preventing formation of the active C3 convertase C3bBb. In addition, it acts as a cofactor for the Factor I-mediated proteolytic inactivation of C3b to iC3b.
REACT_118836 (Reactome) The beta subunit of C4b binding protein binds and inactivates Protein S, a vitamin K dependent anticoagulation factor. This may represent part of a mechanism for fine-tuning the process of phagocytosis (Kask et al. 2004).
REACT_118841 (Reactome) Following the displacement of Bb from C3bBb, Factor I cleaves Factor H-bound C3b producing iC3b, which remains bound to the membrane. The majority of the C3b alpha chain is retained as two fragments which are tethered to the beta chain by disulphide bonds. iC3b is proteolytically inactive and cannot contribute to the complement cascade process, though it still contributes to opsonization.
REACT_118844 (Reactome) Complement factor I binds to the Factor H:C3b complex.
REACT_163715 (Reactome) Ficolin-1 (M-ficolin or FCN1) was shown to localize at the cell surface of circulating monocytes and granulocytes, despite lacking an obvious transmembrane domain, (Teh C et al. 2000; Honore C et al. 2010). Ficolin-1 has also been found in human plasma (Honore C et al. 2008; Wittenborn T et al. 2010; Kjaer TR et al. 2011). Monocytes and macrophages, but not immature dendritic cells were reported to secrete Ficolin-1 into the serum (Honore C et al. 2010). Moreover, early studies revealed its presence in secretory granules of peripheral blood monocytes and granulocytes (Liu Y et al. 2005). Soluble Ficolin-1 was found to form a complex with MASP2, while cell surface-bound Ficolin-1 did not associate with MASP (Honore C et al. 2010; Kjaer TR et al. 2011).

Ficolin-1 specifically recognizes sialic acid and can bind to acetylated compounds such as N-acetylglucosamine (GlcNAc) and N-acetylgalactosamine (GalNAc) (Garlatti V et al. 2007; Gout E et al. 2010; Kjaer TR et al. 2011).

REACT_163747 (Reactome) Human ficolin-2 (L-ficolin, P35 or FCN2) is synthesised in the liver and secreted into the bloodstream where it recognizes various capsulated bacteria and exhibits binding specificity for diverse ligands, such as lipoteichoic acid, 1,3-beta-d-glucan, and acetylated compounds [Lynch NJ et al. 2004; Aoyagi Y et al. 2008; Ma YG et al. 2004; Garlatti V et al. 2007; Gout E et al 2010]. Ficolin-2 also binds to apoptotic HL60, U937, and Jurkat cells [Kuraya M, et al. 2005].
REACT_163758 (Reactome) Ficolin-3 (H-ficolin, FCN3 or Hakata antigen) activates the lectin pathway of complement similar to mannose-binding lectin. Ficolin-3 is composed by a collagen-like strand and three C-terminal recognition domains which bind to carbohydrates on the target surface. Ficolin-3 circulates in plasma associated with mannan-binding lectin-associated serine proteases (MASPs). Upon ligand binding ficolin-3:MASPs complex triggers activation of the lectin pathway [Matsushita M et al. 2002; Teillet F et al. 2008; Zacho RM et al. 2012]. Ficolin-3 (FCN3 or H-ficolin) can specifically recognize Aerococcus viridans [Tsujimura M et al. 2002; Zacho RM et al. 2012]. Ficolin-3 has been shown to bind to patterns of bacterial polysaccharides such as d-fucose and galactose [Garlatti V et al. 2007]. In adition to pathogenic ligands ficolin-3 was reported to bind to apoptotic Jurkat cells [Kuraya M et al. 2005].
REACT_163759 (Reactome) Vitronectin interacts with C5b:C6:C7 complex preventing it from the binding with the cell membrane
REACT_163768 (Reactome) Cleavage of C4 exposes a highly reactive thioester bond on the C4b molecule. The thioester bond is rapidly inactivated by hydrolysis if C4b does not bind to the target cell surface [Sepp A et al 1993].
REACT_163829 (Reactome) CD59, the major inhibitor of the complement membrane attack complex, is an 18–20 kDa glycoprotein, linked to the membrane via a glycosylphosphatidylinositol (GPI)-anchor. It interacts with complement components C8 and C9 during assembly of the membrane attack complex (MAC) and inhibits C9 polymerization, thus preventing the formation of MAC [Lehto T and Meri S. 1993;Rollins SA et al 1991]
REACT_163860 (Reactome) Factor I (FI) inactivates C3 convertase activity by cleavage C3b producing iC3b, which remains bound to the membrane. A final proteolytic cleavage converts iC3b into two molecules, C3c, which is released into solution, and C3dg, which remains attached to the membrane. This cleavage requires CR1, which serves as a cofactor for cleavage of iC3b by factor I (Medof ME et al. 1982).

iC3b and C3dg are active molecules, that can bind CR2 (CD21) to enhance B-cell immunity (Tuveson DA et al.1991; Sarrias MR et al. 2001).

REACT_163870 (Reactome) Complement proteins C8 and C9 can bind to VTN:C5b:C6:C7 to form soluble C5b-C9 complex in plasma. The vitronectin binding to C5b-C9 complex prevents C9 polymerization by rendering it water-soluble and lytic inactive.
REACT_25075 (Reactome) Metastable C3b can bind a wide variety of proteins and carbohydrates expressed on biological surfaces (Coico & Sunshine, 2009; Kimball 2010). This is an essentially random event (Dodds & Law, 1998); binding may be to host or microorganism. However, certain surface sugars have greater C3b binding rates, perhaps explaining variations in microorganism suceptibility (Pangburn, M. in The Complement System, Ed. Rother et al. 1998).
REACT_25166 (Reactome) The cleavage of C4 into C4a and C4b releases an acyl group from the intrachain thioester bond, allowing C4b to bond covalently to any adjacent biological substrates (Dodds & Law 1998). C4 is encoded at two loci, C4A and C4B. The C4b proteins derived from these genes are not identical and have different binding preferences (Law et al 1984, Sepp et al. 1993); C4A-derived C4b binds more efficiently than C4B-derived C4b to amino groups, while C4B-derived C4b is more effective than C4A in binding to hydroxyl groups. The site of C4b deposition is not clearly established (Møller-Kristensen et al. 2003) but generally accepted to be the activating cell membrane surface, though it may be the activating complex itself.
REACT_7946 (Reactome)
REACT_7948 (Reactome) C3(H2O):Factor Bb is a C3 convertase, sometimes referred to as the initial C3 convertase (iC3). The Factor Bb component catalyzes the hydrolysis of C3 to produce C3b and C3a. This reaction is not known to be directly coupled to the association of C3b complexes with a cell surface. It is believed that a small proportion of C3b spontaneously associates with the cell surface, otherwise it is rapidly inactivated (Muller-Eberhard 1988).
REACT_7950 (Reactome)
REACT_7959 (Reactome) C2 is cleaved into the large C2a and the small C2b fragment. This irreversible, extracellular reaction can be catalyzed by activated MBL, generated through the lectin pathway of complement activation (Vorup-Jensen et al. 2000), and by activated C1, generated through the classical pathway (Nasagawa and Stroud 1977). N.B. Early literature refers to the larger fragment of C2 as C2a. However, complement scientists decided that the smaller of all C fragments should be designated with an 'a', the larger with a 'b', changing the nomenclature for C2. For this reason recent literature may refer to the larger C2 fragment as C2b, and the classical C3 convertase as C4bC2b. Throughout this pathway, Reactome uses the current (Feb 2012) Uniprot names which adhere to the original naming practice.
REACT_7965 (Reactome) MBL or ficolins binding to carbohydrates on the target surface results in conformational changes in the lectin:MASPs complex. It in turn promotes a cleavage of proenzyme form of MASP between the CCP2 and the serine protease domains, which results in the generation of the active form. The active form of MASP-2 is able to cleave C4 and C2 to generate the C3 convertase (Vorup-Jensen T et al. 2000; Chen CB and Wallis R 2004). The active form of MASP-1 was shown to facilitate the complement activation by either direct cleavage of complex-bound MASP-2 or cleavage of C2 bound to C4 (Matsushita M et al. 2000; Heja D et al. 2012).
REACT_7966 (Reactome) C3b on a surface binds Factor B from solution to form a complex (Schreiber et al. 1978; Muller-Eberhard 1988).
REACT_7976 (Reactome)
REACT_7977 (Reactome) In this irreversible reaction, the activated C1r subunit of the C1:antibody:antigen complex cleaves the C1s subunit of the complex, activating it in turn (Ziccardi and Cooper 1976). The resulting complex is a C4 activator.
REACT_7978 (Reactome) C1 activation requires interaction with two separate Fc domains, so pentavalent IgM antibody is far more efficient at complement activation than IgG antibody (Muller-Eberhard and Kunkel 1961). Antibody binding results in a conformational change in the C1r component of the C1 complex and a proteolytic cleavage of C1r, activating it (Ziccardi and Cooper 1976). This reaction is irreversible under physiological conditions.
REACT_7981 (Reactome) Factor D, a constitutively active serine protease found in trace amounts in the blood, cleaves a specific Arg-Lys bond in the Factor B component of the soluble C3(H2O):Factor B complex, yielding C3(H2O):Factor Bb and an inactive polypeptide, Factor Ba (Fearon and Austin 1975; Lesavre and Muller-Eberhard 1978; Lesavre et al. 1979; Schreiber et al. 1978).
REACT_7982 (Reactome)
REACT_7983 (Reactome) The MBL polypeptide chain consists of a short N-terminal cysteine-rich region, a collagen-like region comprising 19 Gly-X-Y triplets, a 34-residue hydrophobic stretch, and a C-terminal C-type lectin domain. MBL monomers associate via their cysteine-rich and collagen-like regions to form homotrimers, and these in turn associate into oligomers. The predominant oligomers found in human serum contain three (MBL-I) or four (MBL-II) homotrimers (Fujita et al. 2004; Teillet et al. 2005). Extracellular MBL oligomers circulate in plasma in complexes with MASP1/2. The carbohydrate recognition domain (CRD) of MBL binds carbohydrates with 3- and 4- OH groups in the pyranose ring, such as mannose and N-acetyl-D-glucosamine, in the presence of Ca2+. Such motifs occur on the surfaces of viruses, bacteria, fungi and protozoa. The affinity of any one MBL binding site for a carbohydrate ligand is low, but interaction between multiple binding sites on an MBL oligomer and a repetitive carbohydrate motif on a target surface allow high-avidity binding. The specificity of the MBL binding site (it does not bind glucose or sialic acid) and the requirement for a repeated target motif may account for the failure of MBL to bind human glycoproteins under normal conditions (Petersen et al. 2001). This reaction in particular represents the interaction of MBL with bacterial mannose repeats.
REACT_7986 (Reactome) The complex of C3b:Factor Bb, stabilized on the cell surface by properdin, catalyzes the cleavage of C3 to yield C3b and C3a. The C3b is recruited to the C3b:Factor B complex through its interaction with properdin (Daha et al. 1976; Medicus et al. 1976; Hourcade 2006), yielding the alternate C5 convertase.
REACT_7988 (Reactome) The membrane attack complex is composed of one C5:C6:C7:C8 complex and between 12-15 C9 molecules (Podack et al. 1982 - 12 represented in this reaction).
REACT_7989 (Reactome) The same complexes as for C3 activation are employed for the cleavage of C5. C3 convertases with an additional C3b molecule covalently deposited in the immediate vicinity form the C5 convertases C3bBbC3b and C4b2aC3b, respectively. The second C3b acts like an anvil for C5: it interacts with C5 and presents C5 in the correct conformation for cleavage by the C2a or Bb enzyme.
REACT_7990 (Reactome) C4b and C2a bind to form the classical pathway C3-convertase (C4b2a complex), C3b and the Bb fragment of Factor B form the alternative pathway C3 convertase. The C3(H2O):Bb C3 convertase is sometimes called the initiating convertase, and the C5 convertases also have C3 convertase activity (Rawal & Pangburn 2001).
REACT_8002 (Reactome) The alpha chain of C4 is cleaved, releasing an N-terminal portion of this chain as C4a. The beta and gamma chains are not cleaved and remain linked to the alpha chain by disulfide bonds (Nagasawa et al. 1976, 1980). The resulting C4b heterotrimer undergoes a gross conformational change; the internal thioester in C4b becomes exposed and able to form covalent bonds with surrounding molecules (Law and Dodds 1997). A large proportion of the bonds formed are with water, but some will attach C4b to biological surfaces (Rother et al. 1998). This irreversible reaction can be catalyzed by activated MBL, generated through the lectin pathway of complement activation (Fujita et al. 2004; Hajela et al. 2002), and by activated C1, generated through the classical pathway (Muller-Eberhard and Lepow 1965).

N.B. Humans have two highly polymorphic loci for Complement factor 4, C4A and C4B. C4A alleles carry the Rodgers (Rg) blood group antigens while the C4B alleles carry the Chido (Ch) blood group antigens. The two loci encode non identical C4 peptides; C4 derived from C4A reacts more rapidly with the amino groups of peptide antigens while C4B allotypes react more rapidly with the hydroxyl group of carbohydrate antigens. The names of the two loci are always represented in uppercase. C4a and C4b refer to the peptide products of Complement Factor 4 cleavage.
REACT_8007 (Reactome) The thioester linkage between cysteine residue 1010 and glutamine residue 1013 in the alpha chain of Complement factor 3 (C3) can spontaneously hydrolyze, yielding so-called C3(H2O) (Tack et al. 1980; Pangburn & Muller-Eberhard 1980; Pangburn et al. 1981). Thioester bond hydrolysis causes conformational rearrangements that give C3(H2O) the ability to bind Factor B. The spontaneous hydrolysis rate of C3 under physiological conditions and temperature is about l% per hour, thus the C3b-like properties of C3(H2O) provide a continuous low level initiation of the alternative pathway of complement activation (Pangburn & Muller-Eberhard 1983). If not bound by Factor B, C3(H2O) binds Factor H and is inactivated by Factor I
REACT_8013 (Reactome) Thioester bond hydrolysis causes conformational rearrangements that give C3(H2O) the ability to bind Factor B (Schreiber et al. 1978). The spontaneous hydrolysis rate of C3 under physiological conditions and temperature is about l% per hour, thus the C3b-like properties of C3(H2O) provide a continuous low level initiation of the alternative pathway of complement activation (Pangburn & Muller-Eberhard 1983).
REACT_8014 (Reactome) C4b and C2a form a complex termed the classical pathway C3 convertase (Muller-Eberhard et al. 1967). C2a that fails to bind C4b is rapidly inactivated.
REACT_8018 (Reactome) C3b:Bb is naturally labile with a half-life of ~90 s; association of the complex with properdin extends the half-life to ~30 min. (Medicus et al. 1976). Properdin is found in the blood as a mixture of multivalent oligomers: 30% dimers, 45% trimers, 10% tetramers, and 15% higher oligomers. Monomers associate with one another in a head-to-tail arrangement, producing closed circular structures (Smith et al. 1984). These features suggest that the properdin oligomer associated with a C3b:Bb complex on a surface such as a cell membrane can facilitate recruitment of additional C3b:Bb complexes to the site (Farries et al. 1988; Hourcade 2006).
REACT_8022 (Reactome) C5 convertases are serine proteases that cleave C5 with high efficiency; the C3 convertases can cleave C5 but have a poor affinity for C5, with a Km of 6-9 microM. The high affinity C5 convertases are generated when the low affinity C3/C5 convertases such as C4b:C2a deposit C3b by cleaving native C3. These C3b-containing C3/C5 convertases have Km values of 0.005 microM, well below the normal concentration of C5 in blood (0.37 microM). They have very low Vmax rates, just one C5 cleaved per 1–4 min per enzyme (Rawal & Pangburn 1998).
REACT_8026 (Reactome) Factor D, a constitutively active serine protease found in trace amounts in the blood, cleaves a specific Arg-Lys bond in the Factor B component of the cell surface-associated C3b:Factor B complex, yielding the alternate C3 convertase C3bBb on the surface and releasing an inactive polypeptide, Factor Ba (Lesavre and Muller-Eberhard 1978; Lesavre et al. 1979; Schreiber et al. 1978).
VTN(20-?)REACT_163759 (Reactome)
VTN:C5b:C6:C7:C8:C9ArrowREACT_163870 (Reactome)
VTN:C5b:C6:C7ArrowREACT_163759 (Reactome)
VTN:C5b:C6:C7REACT_163870 (Reactome)
iC3bArrowREACT_118650 (Reactome)
iC3bArrowREACT_118841 (Reactome)
thioester-C1010-Q1013-C4bArrowREACT_8002 (Reactome)
thioester-C1010-Q1013-C4bREACT_118763 (Reactome)
thioester-C1010-Q1013-C4bREACT_163768 (Reactome)
thioester-C1010-Q1013-C4bREACT_25166 (Reactome)