title: C3 nephritic factor (C3NeF): dissociation of cell-bound and fluid phase stabilization of alternative pathway C3 convertase.
abstract: Fluid phase C3 conversion by C3 nephritic factor (C3NeF) is usually easily detectable and forms the basis of the C3NeF screening test. We have described a group of patients with membranoproliferative glomerulonephritis or partial lipodystrophy and hypocomplementaemia who have an unusual C3NeF which stabilizes cell-bound C3 convertase of the alternative pathway (C3bBb) but causes such weak fluid phase C3 conversion that a C3NeF screening test is negative. These patients have low concentrations of C5 in serum.
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D003166:Complement Activating Enzymes / Q000097:blood*; D003167:Complement Activation; D003178:Complement C3 Nephritic Factor / Q000032:analysis*; D050577:Complement C3-C5 Convertases / Q000097:blood*; D003182:Complement C5 / Q000032:analysis; D003169:Complement Inactivator Proteins / Q000032:analysis*; D003170:Complement Pathway, Alternative; D005260:Female; D005921:Glomerulonephritis / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D008060:Lipodystrophy / Q000276:immunology*; D008297:Male
chemical_list: D003178:Complement C3 Nephritic Factor; D003182:Complement C5; D003169:Complement Inactivator Proteins; D007074:Immunoglobulin G; D003166:Complement Activating Enzymes; D050577:Complement C3-C5 Convertases