Tumour necrosis factor a and interleukin 1 beta in relapse of Crohn's disease

Background Concentrations of proinflammatory cytokines are increased in the intestinal mucosa of patients with active Crohn's disease. Experimental im munotherapeutic interventions with anticytokine agents in refractory Crohn' s disease show that tumour necrosis factor cw (TNF alpha) may be an importa nt mediator,of inflammation. We investigated the relation between productio n of TNF alpha and interleukin 1 beta by mononuclear cells of the colonic l amina propria in patients with remitting Crohn's disease and the risk of re lapse. Methods We followed up 137 patients with Crohn's disease in steroid-induced remission for 1 year. Secretion of proinflammatory cytokines (tumour necro sis factor alpha [TNF alpha] and interleukin 1 beta) was assessed after sho rt-term culture of human lamina propria mononuclear cells. Findings Increased secretion of TNF alpha and interleukin 1 beta were predi ctive for acute relapses within the next year. Site and extent of disease, baseline demographics, and serum acute-phase proteins had little predictive value. Interpretation TNF alpha is important as a target molecule for immune inter ventions in Crohn's disease. The capacity to produce TNFa or interleukin 1 beta may identify patients who would benefit from anti-inflammatory remissi on maintenance.