Spontaneous suppressor cell function in inflammatory bowel disease.

We investigated suppressor cell activity in the peripheral blood of 39 patients with inflammatory bowel disease (30 Crohn's disease and 9 ulcerative colitis) by the short-lived suppressor cell assay. There was a significant decrease in the suppressor cell activity in patients with inflammatory bowel disease (IBD), compared to 26 healthy subjects studied simultaneously. Five other patients with acute bacterial infections had normal suppressor activity. A group of 14 IBD patients was also investigated for concanavalin A-induced suppressor cell activity and decreased suppressor function was confirmed. A significant positive correlation was found between the two assays. A defect in suppressor cell activity may permit the expression or maintenance of immunologically mediated damage to the gut in IBD.