title: C3 polymorphism and circulating immune complexes in patients with multiple sclerosis.
abstract: The phenotypes of the complement factor C3 have been evaluated in 60 patients with multiple sclerosis (M.S.), and the results correlated to the occurrence of circulating immune complexes (CIC). A significantly increased frequency of the C3F-gene was found among the patients, and closely associated with the occurrence of CIC. A relative risk incidence of 4.1 was found for C3F-positive individuals among M.S. patients with detectable CIC. Low C3 levels in serum were found in 30% of the patients, almost all belonged to the group without CIC and showed a C3-type distribution similar to normal controls. A different immunological reaction pattern (type II reaction) in these patients seems possible, and a genetically determined immunological abnormality predisposing to M.S. is therefore suggested.
mesh_terms: D000483:Alleles; D000936:Antigen-Antibody Complex; D003176:Complement C3 / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000235:genetics*; D010641:Phenotype; D011110:Polymorphism, Genetic
chemical_list: D000936:Antigen-Antibody Complex; D003176:Complement C3