Neutrophil apoptosis is delayed in patients with inflammatory bowel disease

Delayed neutrophil apoptosis is a feature of persistent acute inflammation. Neutrophil-mediated damage has been shown to be associated with the develo pment of inflammatory bowel disease (IBD). Persistence of these cells both at the colonic site and circulation may further contribute to IBD. The aims of this study were to determine whether neutrophils isolated from IBD pati ents delay apoptosis and to investigate possible mechanisms involved in thi s delay. We studied 20 patients with IBD, 13 with Crohn's disease, and 7 wi th ulcerative colitis, all of whom were undergoing intestinal resection for symptomatic disease. Seventeen patients undergoing elective resection of c olon cancer acted as operative controls. Systemic, mesenteric arterial, and mesenteric venous blood was harvested. Neutrophils isolated from patients with IBD showed decreased spontaneous apoptosis compared to cancer patients . Mesenteric venous serum of IBD patients contributed to this delay, which contained higher concentrations of interleukin-8 (IL-8). Pro-caspase 3 expr ession was also reduced in IBD neutrophils, which may contribute to decreas ed spontaneous and Pas antibody-induced apoptosis. Neutrophil apoptosis may be altered in Crohn's disease and ulcerative colitis through release of an ti-apoptotic cytokines and altered caspase expression. The alterations in c ell death mechanisms may lead to persistence of the inflammatory response a ssociated with IBD.