Cytokine production in whole blood cell cultures of patients with Crohn's disease and ulcerative colitis

Abstract

Levels of the cytokines interleukin-1-alpha, -1-beta, and -2 (IL-1-alpha, IL-1-beta, IL-2), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) were measured in the mitogen-stimulated whole blood cell cultures from 96 patients with Crohn's disease (48 untreated, 12 treated with sulfasalazine, 36 treated with corticosteroids), 74 patients with ulcerative colitis (21 untreated, 25 treated with sulfasalazine, 28 steroid treated), and 360 healthy controls. The cytokines were measured 4 days after induction by a sensitive immunoenzyme assay. In the blood cell cultures of the untreated and sulfasalazine treated patients with Crohn's disease and ulcerative colitis higher levels of TNF-alpha, IL-1-alpha and IL-1-beta were found whereas IL-2 production was decreased and IFN-gamma-production was not significantly different as compared to the controls. Leukocytes of the corticosteroid-treated patients with both diagnoses showed a lower production of all measured cytokines compared to the untreated patients. The same results were obtained, when the somewhat different counts of mononuclear cells in the peripheral blood of the patients and controls were taken into account. The elevated production of proinflammatory cytokines in the blood cell cultures suggests a systemic immune activation in patients with inflammatory bowel disease.