title: Immune complexes in ulcerative colitis and Crohn's disease.
abstract: Sera from 156 patients with ulcerative colitis and Crohn's disease were tested for the presence of immune complexes, by the detection of anti-complementary activity and 125I-labelled Clq precipitation. Using aggregated IgG, a comparison between the two tests indicated that the anti-complementary test was most sensitive to aggregates of 11S in size, while the 125I-labelled Clq test detected aggregates over 20S in size. Excess anti-complementary activity was common in patients with active bowel disease, and in those with extra-intestinal manifestations, particularly acute arthritis, ankylosing spondylitis and liver disease. Large complexes were only common in patients with liver disease. Immune complexes in the gut mucosa may play a role in the pathogenesis of these diseases, and the deposition of circulatory immune complexes may explain at least some of the extra-intestinal manifestations.
mesh_terms: D000936:Antigen-Antibody Complex; D001168:Arthritis / Q000209:etiology; D003093:Colitis, Ulcerative / Q000150:complications / Q000276:immunology*; D003174:Complement C1 Inactivator Proteins; D003424:Crohn Disease / Q000150:complications / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G; D008107:Liver Diseases / Q000209:etiology
chemical_list: D000936:Antigen-Antibody Complex; D003174:Complement C1 Inactivator Proteins; D007074:Immunoglobulin G