Background Investigation of anti-colon antibodies may be simplified if a sensitive method and homogeneous source of antigen were available.

Aims To examine the anti-colon antibody response using human colonic carcinoma cell lines as antigen.

Subjects Patients with inflammatory bowel disease and other gastrointestinal disorders and healthy controls were studied.

Results Sera demonstrated immunoreactivity against each of the cell lines, but different epitopes were recognised. Applying whole Caco-2 cells as antigen in an ELISA, the prevalence of anti-colon antibodies was significantly greater in patients with ulcerative colitis (36%) than Crohn’s disease (13%), other gastrointestinal disorders (13%) and healthy controls (0) (p<0.05). The immune response was not associated with one predominant antigen.

Conclusions Fixed whole cell ELISA is a simple and feasible method for studying the anti-colon antibody response. This response is non-specific, being directed against multiple antigens, and is likely to be an epiphenomenon of inflammatory bowel disease, more so for ulcerative colitis than Crohn’s disease.