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. 1989 Jan;66(1):20–25.

The plasma protein which inhibits complement-mediated prevention of immune precipitation is an Fc binding protein.

A E Ahmed 1, P Bird 1, I C McKay 1, K Whaley 1
PMCID: PMC1385114  PMID: 15493257

Abstract

A glycoprotein (gp60) that inhibits complement-mediated prevention of immune precipitation (PIP) has been purified from normal serum. [125I]gp60 binds to IgG but not to IgA or IgM. The binding site has been shown to be localized on the Fc piece. The binding of radiolabelled gp60 to IgG has been analysed by direct binding and Scatchard, double-reciprocal and Hill plots. The mean affinity constant of gp60 for IgG is 1.56 x 10(8) l/mol and there appears to be a single class of binding sites for gp60 on IgG. Saturation was achieved when one molecule of gp60 was bound to each molecule of IgG. In competition inhibition assays, gp60 was shown to compete with C1q and IgM and IgG rheumatoid factors. The ability to inhibit C1q binding suggests that gp60 inhibits PIP by preventing binding and activation of C1. The possibility that gp60 is a fluid-phase Fc gamma receptor is discussed. See also the note added in proof.

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Selected References

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

  1. Bird P., Lowe J., Stokes R. P., Bird A. G., Ling N. R., Jefferis R. The separation of human serum IgG into subclass fractions by immunoaffinity chromatography and assessment of specific antibody activity. J Immunol Methods. 1984 Jun 8;71(1):97–105. doi: 10.1016/0022-1759(84)90209-6. [DOI] [PubMed] [Google Scholar]
  2. Burton D. R. Immunoglobulin G: functional sites. Mol Immunol. 1985 Mar;22(3):161–206. doi: 10.1016/0161-5890(85)90151-8. [DOI] [PubMed] [Google Scholar]
  3. Fridman W. H., Nelson R. A., Jr, Liabeuf A. Production of an immunoglobulin-binding factor (IBF) by antigen-stimulated lymph node lymphocytes. J Immunol. 1974 Sep;113(3):1008–1016. [PubMed] [Google Scholar]
  4. Fridman W. H., Rabourdin-Combe C., Neauport-Sautes C., Gisler R. H. Characterization and function of T cell Fc gamma receptor. Immunol Rev. 1981;56:51–88. doi: 10.1111/j.1600-065x.1981.tb01047.x. [DOI] [PubMed] [Google Scholar]
  5. Goetzl E. J., Metzger H. Affinity labeling of a mouse myeloma protein which binds nitrophenyl ligands. Kinetics of labeling and isolation of a labeled peptide. Biochemistry. 1970 Mar 3;9(5):1267–1278. doi: 10.1021/bi00807a031. [DOI] [PubMed] [Google Scholar]
  6. Hughes-Jones N. C. Functional affinity constants of the reaction between 125I-labelled C1q and C1q binders and their use in the measurement of plasma C1q concentrations. Immunology. 1977 Feb;32(2):191–198. [PMC free article] [PubMed] [Google Scholar]
  7. Hughes-Jones N. C., Gardner B. The reaction between the complement subcomponent C1q, IgG complexes and polyionic molecules. Immunology. 1978 Mar;34(3):459–463. [PMC free article] [PubMed] [Google Scholar]
  8. Khayat D., Dux Z., Anavi R., Shlomo Y., Witz I. P., Ran M. Circulating cellfree Fc gamma 2b/gamma 1 receptor in normal mouse serum: its detection and specificity. J Immunol. 1984 May;132(5):2496–2501. [PubMed] [Google Scholar]
  9. 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]
  10. Markwell M. A., Fox C. F. Surface-specific iodination of membrane proteins of viruses and eucaryotic cells using 1,3,4,6-tetrachloro-3alpha,6alpha-diphenylglycoluril. Biochemistry. 1978 Oct 31;17(22):4807–4817. doi: 10.1021/bi00615a031. [DOI] [PubMed] [Google Scholar]
  11. McPhaden A. R., Whaley K. Modulation of C2 biosynthesis by antigen-antibody complexes. J Clin Lab Immunol. 1982 Jan;7(1):15–19. [PubMed] [Google Scholar]
  12. Mitchell W. S., Naama J. K., Veitch J., Whaley K. IgM-RF prevents complement-mediated inhibition of immune precipitation. Immunology. 1984 Jul;52(3):445–448. [PMC free article] [PubMed] [Google Scholar]
  13. Molenaar J. L., van Galen M., Hannema A. J., Zeijlemaker W., Pondman K. W. Spontaneous release of Fc receptor-like material from human lymphoblastoid cell lines. Eur J Immunol. 1977 Apr;7(4):230–236. doi: 10.1002/eji.1830070409. [DOI] [PubMed] [Google Scholar]
  14. Møller N. P. Fc-mediated immune precipitation. I. A new role of the Fc-portion of IgG. Immunology. 1979 Nov;38(3):631–640. [PMC free article] [PubMed] [Google Scholar]
  15. Møller N. P., Steensgaard J. Fc-mediated immune precipitation. II. Analysis of precipitating immune complexes by rate-zonal ultracentrifugation. Immunology. 1979 Nov;38(3):641–648. [PMC free article] [PubMed] [Google Scholar]
  16. Naama J. K., Hamilton A. O., Yeung-Laiwah A. C., Whaley K. Prevention of immune precipitation by purified classical pathway complement components. Clin Exp Immunol. 1984 Nov;58(2):486–492. [PMC free article] [PubMed] [Google Scholar]
  17. Naama J. K., Holme E., Hamilton E., Whaley K. Prevention of immune precipitation by purified components of the alternative pathway. Clin Exp Immunol. 1985 Apr;60(1):169–177. [PMC free article] [PubMed] [Google Scholar]
  18. Naama J. K., Mitchell W. S., Whaley K. Inhibition of complement-mediated solubilization of antigen-antibody complexes by sera from patients with rheumatoid arthritis. Clin Exp Immunol. 1983 Nov;54(2):429–438. [PMC free article] [PubMed] [Google Scholar]
  19. Pure E., Durie C. J., Summerill C. K., Unkeless J. C. Identification of soluble Fc receptors in mouse serum and the conditioned medium of stimulated B cells. J Exp Med. 1984 Dec 1;160(6):1836–1849. doi: 10.1084/jem.160.6.1836. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Reid F. M., Peel M. G., Jarrett F., Sandilands G. P. Modulation of human peripheral blood lymphocyte Fc gamma receptors by immune complexes: recovery of Fc gamma receptors in the presence of normal human serum. Immunology. 1983 Feb;48(2):281–289. [PMC free article] [PubMed] [Google Scholar]
  21. Sandilands G. P., Peel M. G., MacSween R. N. Comparison of Fc gamma-receptors isolated from normal human serum and peripheral blood lymphocytes. J Clin Lab Immunol. 1984 Sep;15(1):39–44. [PubMed] [Google Scholar]
  22. Schifferli J. A., Bartolotti S. R., Peters D. K. Inhibition of immune precipitation by complement. Clin Exp Immunol. 1980 Nov;42(2):387–394. [PMC free article] [PubMed] [Google Scholar]
  23. Schifferli J. A., Peters D. K. Complement, the immune-complex lattice, and the pathophysiology of complement-deficiency syndromes. Lancet. 1983 Oct 22;2(8356):957–959. doi: 10.1016/s0140-6736(83)90464-6. [DOI] [PubMed] [Google Scholar]
  24. Schifferli J. A., Woo P., Peters D. K. Complement-mediated inhibition of immune precipitation. I. Role of the classical and alternative pathways. Clin Exp Immunol. 1982 Mar;47(3):555–562. [PMC free article] [PubMed] [Google Scholar]
  25. Tenner A. J., Lesavre P. H., Cooper N. R. Purification and radiolabeling of human C1q. J Immunol. 1981 Aug;127(2):648–653. [PubMed] [Google Scholar]
  26. Whaley K., Lappin D., McPhaden A. R., Riches D. W., Sandilands G. P. A comparison of the effects of heat-aggregated and chemically cross-linked IgG on monocyte C2 production. Immunology. 1983 Jul;49(3):457–461. [PMC free article] [PubMed] [Google Scholar]

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