Cellular and humoral response to Kunin antigen (CA) in ulcerative colitis and Crohn's disease

In 18 patients with ulcerative colitis and in 8 with Crohn's disease two tests were performed simultaneously: a) the leukocyte migration inhibition test using Kunin antigen, and b) titration of serum antibodies against this antigen. Leukocyte migration was studied by the agarose plate technique. At the concentration of 25 microgram/ml, Kunin antigen inhibited migration in five cases of ulcerative colitis and in one with Crohn's disease. This phenomenon was not observed in any of 33 control subjects. All patients in whom leukocyte migration was inhibited were in the active phase of the disease. Titers of antibodies against Kunin antigen were determined by the passive hemagglutination test in an expended group of patients comprising 61 with Crohn's disease. The antibody titer, expressed as the geometric mean of hemagglutinin titers, was nearly three times as high in patients as in 324 healthy controls. The titers were not correlated either with clinical activity of both diseases or with the results of the leukocyte migration inhibition test. The significance of these findings is discussed in the light of other data indicating that Kunin antigen plays a role in the pathogenesis of inflammatory bowel disease.