Skip to main content
PMC home page
Biochemical Journal logoLink to Biochemical Journal
. 1997 Sep 1;326(Pt 2):553–561. doi: 10.1042/bj3260553

Interactions between human complement components factor H, factor I and C3b.

C J Soames 1, R B Sim 1
PMCID: PMC1218704  PMID: 9291131

Abstract

Using a microtitre plate assay, direct binding between complement factors I and H was demonstrated, and ligand blotting indicated that factor H interacts with the heavy chain of factor I. Similarly, direct C3(NH3)-factor I and C3(NH3)-factor H binding was characterized [where C3(NH3) is a form of C3 that is cleaved by factor I in the presence of factor H]. Both factor H and factor I interacted with both chains of C3(NH3) in ligand blotting. Binding reactions between all three pairs of components were highly dependent on ionic strength, and showed similar pH optima. Binding assays with all three components present led to the following conclusions. (a) Binding sites for C3(NH3) and factor I on factor H do not overlap, and binding of factor I and C3(NH3) to soluble factor H promotes the weak factor I-C3(NH3) interaction. (b) Anomalies arise with immobilized factor H, which may be artefactual or may reflect the physiological situation. (c) Similarly, binding sites on factor I for C3(NH3) and for factor H do not overlap, and binding of factor H and C3(NH3) to factor I promotes direct factor H-C3(NH3) interactions. Based on these results, a model of the interactions between factor H, factor I and C3(NH3) leading to the processing of C3(NH3) is proposed.

Full Text

The Full Text of this article is available as a PDF (461.5 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Alsenz J., Schulz T. F., Lambris J. D., Sim R. B., Dierich M. P. Structural and functional analysis of the complement component factor H with the use of different enzymes and monoclonal antibodies to factor H. Biochem J. 1985 Dec 15;232(3):841–850. doi: 10.1042/bj2320841. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Barlow P. N., Steinkasserer A., Norman D. G., Kieffer B., Wiles A. P., Sim R. B., Campbell I. D. Solution structure of a pair of complement modules by nuclear magnetic resonance. J Mol Biol. 1993 Jul 5;232(1):268–284. doi: 10.1006/jmbi.1993.1381. [DOI] [PubMed] [Google Scholar]
  3. Becherer J. D., Alsenz J., Esparza I., Hack C. E., Lambris J. D. Segment spanning residues 727-768 of the complement C3 sequence contains a neoantigenic site and accommodates the binding of CR1, factor H, and factor B. Biochemistry. 1992 Feb 18;31(6):1787–1794. doi: 10.1021/bi00121a029. [DOI] [PubMed] [Google Scholar]
  4. Bork P., Ouzounis C., McEntyre J. Ready for a motif submission? A proposed checklist. Trends Biochem Sci. 1995 Mar;20(3):104–104. doi: 10.1016/s0968-0004(00)88974-4. [DOI] [PubMed] [Google Scholar]
  5. Catterall C. F., Lyons A., Sim R. B., Day A. J., Harris T. J. Characterization of primary amino acid sequence of human complement control protein factor I from an analysis of cDNA clones. Biochem J. 1987 Mar 15;242(3):849–856. doi: 10.1042/bj2420849. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Crossley L. G., Porter R. R. Purification of the human complement control protein C3b inactivator. Biochem J. 1980 Oct 1;191(1):173–182. doi: 10.1042/bj1910173. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Davis A. E., 3rd, Harrison R. A. Structural characterization of factor I mediated cleavage of the third component of complement. Biochemistry. 1982 Nov 9;21(23):5745–5749. doi: 10.1021/bi00266a003. [DOI] [PubMed] [Google Scholar]
  8. DiScipio R. G. The binding of human complement proteins C5, factor B, beta 1H and properdin to complement fragment C3b on zymosan. Biochem J. 1981 Dec 1;199(3):485–496. doi: 10.1042/bj1990485. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. DiScipio R. G. Ultrastructures and interactions of complement factors H and I. J Immunol. 1992 Oct 15;149(8):2592–2599. [PubMed] [Google Scholar]
  10. Dodds A. W. Small-scale preparation of complement components C3 and C4. Methods Enzymol. 1993;223:46–61. doi: 10.1016/0076-6879(93)23037-n. [DOI] [PubMed] [Google Scholar]
  11. Ekdahl K. N., Nilsson U. R., Nilsson B. Inhibition of factor I by diisopropylfluorophosphate. Evidence of conformational changes in factor I induced by C3b and additional studies on the specificity of factor I. J Immunol. 1990 Jun 1;144(11):4269–4274. [PubMed] [Google Scholar]
  12. Fairbanks G., Steck T. L., Wallach D. F. Electrophoretic analysis of the major polypeptides of the human erythrocyte membrane. Biochemistry. 1971 Jun 22;10(13):2606–2617. doi: 10.1021/bi00789a030. [DOI] [PubMed] [Google Scholar]
  13. Farries T. C., Lachmann P. J., Harrison R. A. Analysis of the interaction between properdin and factor B, components of the alternative-pathway C3 convertase of complement. Biochem J. 1988 Aug 1;253(3):667–675. doi: 10.1042/bj2530667. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Fishelson Z., Horstmann R. D., Müller-Eberhard H. J. Regulation of the alternative pathway of complement by pH. J Immunol. 1987 May 15;138(10):3392–3395. [PubMed] [Google Scholar]
  15. Fraker P. J., Speck J. C., Jr Protein and cell membrane iodinations with a sparingly soluble chloroamide, 1,3,4,6-tetrachloro-3a,6a-diphrenylglycoluril. Biochem Biophys Res Commun. 1978 Feb 28;80(4):849–857. doi: 10.1016/0006-291x(78)91322-0. [DOI] [PubMed] [Google Scholar]
  16. Goldberger G., Bruns G. A., Rits M., Edge M. D., Kwiatkowski D. J. Human complement factor I: analysis of cDNA-derived primary structure and assignment of its gene to chromosome 4. J Biol Chem. 1987 Jul 25;262(21):10065–10071. [PubMed] [Google Scholar]
  17. Griffith I. P. The effect of cross-links on the mobility of proteins in dodecyl sulphate-polyacrylamide gels. Biochem J. 1972 Feb;126(3):553–560. doi: 10.1042/bj1260553. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Hirani S., Lambris J. D., Müller-Eberhard H. J. Structural analysis of the asparagine-linked oligosaccharides of human complement component C3. Biochem J. 1986 Jan 15;233(2):613–616. doi: 10.1042/bj2330613. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Isenman D. E., Podack E. R., Cooper N. R. The interaction of C5 with C3b in free solution: a sufficient condition for cleavage by a fluid phase C3/C5 convertase. J Immunol. 1980 Jan;124(1):326–331. [PubMed] [Google Scholar]
  20. Kalli K. R., Hsu P. H., Bartow T. J., Ahearn J. M., Matsumoto A. K., Klickstein L. B., Fearon D. T. Mapping of the C3b-binding site of CR1 and construction of a (CR1)2-F(ab')2 chimeric complement inhibitor. J Exp Med. 1991 Dec 1;174(6):1451–1460. doi: 10.1084/jem.174.6.1451. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Kazatchkine M. D., Fearon D. T., Austen K. F. Human alternative complement pathway: membrane-associated sialic acid regulates the competition between B and beta1 H for cell-bound C3b. J Immunol. 1979 Jan;122(1):75–81. [PubMed] [Google Scholar]
  22. Koistinen V., Wessberg S., Leikola J. Common binding region of complement factors B, H and CR1 on C3b revealed by monoclonal anti-C3d. Complement Inflamm. 1989;6(4):270–280. doi: 10.1159/000463102. [DOI] [PubMed] [Google Scholar]
  23. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  24. Lambris J. D., Avila D., Becherer J. D., Müller-Eberhard H. J. A discontinuous factor H binding site in the third component of complement as delineated by synthetic peptides. J Biol Chem. 1988 Aug 25;263(24):12147–12150. [PubMed] [Google Scholar]
  25. Nilsson U. R., Storm K. E., Elwing H., Nilsson B. Conformational epitopes of C3 reflecting its mode of binding to an artificial polymer surface. Mol Immunol. 1993 Feb;30(3):211–219. doi: 10.1016/0161-5890(93)90050-l. [DOI] [PubMed] [Google Scholar]
  26. Pangburn M. K., Müller-Eberhard H. J. Complement C3 convertase: cell surface restriction of beta1H control and generation of restriction on neuraminidase-treated cells. Proc Natl Acad Sci U S A. 1978 May;75(5):2416–2420. doi: 10.1073/pnas.75.5.2416. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Pangburn M. K., Müller-Eberhard H. J. Kinetic and thermodynamic analysis of the control of C3b by the complement regulatory proteins factors H and I. Biochemistry. 1983 Jan 4;22(1):178–185. doi: 10.1021/bi00270a026. [DOI] [PubMed] [Google Scholar]
  28. Pangburn M. K., Schreiber R. D., Müller-Eberhard H. J. 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. J Exp Med. 1977 Jul 1;146(1):257–270. doi: 10.1084/jem.146.1.257. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Perkins S. J., Nealis A. S., Sim R. B. Oligomeric domain structure of human complement factor H by X-ray and neutron solution scattering. Biochemistry. 1991 Mar 19;30(11):2847–2857. doi: 10.1021/bi00225a017. [DOI] [PubMed] [Google Scholar]
  30. Perkins S. J., Sim R. B. Molecular modelling of human complement component C3 and its fragments by solution scattering. Eur J Biochem. 1986 May 15;157(1):155–168. doi: 10.1111/j.1432-1033.1986.tb09652.x. [DOI] [PubMed] [Google Scholar]
  31. Perkins S. J., Smith K. F., Sim R. B. Molecular modelling of the domain structure of factor I of human complement by X-ray and neutron solution scattering. Biochem J. 1993 Oct 1;295(Pt 1):101–108. doi: 10.1042/bj2950101. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Ripoche J., Day A. J., Harris T. J., Sim R. B. The complete amino acid sequence of human complement factor H. Biochem J. 1988 Jan 15;249(2):593–602. doi: 10.1042/bj2490593. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Scott J. D., Fothergill J. E. A general method for affinity purification of complement component C3b using factor H-sepharose. Biochem J. 1982 Sep 1;205(3):575–580. doi: 10.1042/bj2050575. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Sim E., Palmer M. S., Puklavec M., Sim R. B. Monoclonal antibodies against the complement control protein factor H (beta 1 H). Biosci Rep. 1983 Dec;3(12):1119–1131. doi: 10.1007/BF01120205. [DOI] [PubMed] [Google Scholar]
  35. Sim E., Sim R. B. Enzymic assay of C3b receptor on intact cells and solubilized cells. Biochem J. 1983 Feb 15;210(2):567–576. doi: 10.1042/bj2100567. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Sim R. B., Day A. J., Moffatt B. E., Fontaine M. Complement factor I and cofactors in control of complement system convertase enzymes. Methods Enzymol. 1993;223:13–35. doi: 10.1016/0076-6879(93)23035-l. [DOI] [PubMed] [Google Scholar]
  37. Sim R. B., DiScipio R. G. Purification and structural studies on the complement-system control protein beta 1H (Factor H). Biochem J. 1982 Aug 1;205(2):285–293. doi: 10.1042/bj2050285. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Weiler J. M., Daha M. R., Austen K. F., Fearon D. T. Control of the amplification convertase of complement by the plasma protein beta1H. Proc Natl Acad Sci U S A. 1976 Sep;73(9):3268–3272. doi: 10.1073/pnas.73.9.3268. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Whaley K., Ruddy S. Modulation of the alternative complement pathways by beta 1 H globulin. J Exp Med. 1976 Nov 2;144(5):1147–1163. doi: 10.1084/jem.144.5.1147. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. de Bruijn M. H., Fey G. H. Human complement component C3: cDNA coding sequence and derived primary structure. Proc Natl Acad Sci U S A. 1985 Feb;82(3):708–712. doi: 10.1073/pnas.82.3.708. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. von Zabern I., Bloom E. L., Chu V., Gigli I. The fourth component of human complement treated with amines or chaotropes or frozen-thawed (C4b-like C4): interaction with C4 binding protein and cleavage by C3b/C4b inactivator. J Immunol. 1982 Mar;128(3):1433–1438. [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES