Serum and tissue autoantibodies to colonic epithelium in ulcerative colitis

Sera and colonic tissue-bound immunoglobulin extracts from patients with ulcerative colitis and disease controls were examined immunohistochemically and by killer cell cytotoxicity assay for the presence of anticolonic epithelial autoantibodies. IgG yields in the tissue extracts from patients with colitis and control subjects were similar, and the extracts were uniformly autoantibody negative. Of 41 sera from patients with inflammatory bowel disease, 'classical' anticolon antibody was present in 41% and was commoner in patients with sclerosing cholangitis. Cytotoxic anticolon antibody was present in 20% overall and was strongly associated with disease activity; it did not correlate with the presence of 'classical' anticolon antibody. The heterogeneous and non-universal antiepithelial autoantibody response and the failure to detect tissue bound autoantibody in vivo argue against the hypothesis that humoral autoimmunity is of major importance in the pathogenesis of ulcerative colitis.