Serum Fc gamma-receptor-like molecules in primary biliary cirrhosis: a possible immunoregulatory mechanism.
Functionally active Fc gamma-receptor-like molecules were isolated from normal human serum by affinity chromatography and shown to have an apparent molecular weight (MW) of approximately 60,000 as assessed by SDS-polyacrylamide gel electrophoresis. These low MW Fc gamma-receptor-like molecules were found to be significantly reduced in whole serum, and in all of six serum fractions, obtained from patients with primary biliary cirrhosis (PBC). A high MW IgG-binding factor, with partial Fc gamma-receptor-like activity, was also found in PBC serum. This factor was also observed to a lesser extent in normal serum. Detailed analysis of this factor suggests that it is a large macromolecule consisting of antigen (unknown). IgG class antibody and 60K Fc gamma-receptor-like molecules. Binding of serum Fc gamma R-like molecules to immune complexes may account for the apparent reduction in Fc gamma-receptor-like activity observed in whole PBC serum. These macromolecules may play an important role in immunoregulation.
D000328:Adult; D000368:Aged; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006386:Hemagglutination Tests; D006801:Humans; D007163:Immunosorbent Techniques; D008105:Liver Cirrhosis, Biliary / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011961:Receptors, Fc / Q000032:analysis* / Q000276:immunology; D017452:Receptors, IgG; D012397:Rosette Formation
D011961:Receptors, Fc; D017452:Receptors, IgG