Circulating cell-derived microparticles in Crohn's disease.

Procoagulant membrane microparticles can be released from activated or apoptotic cells in response to various environmental stimuli. The aim of this study was to investigate the presence of microparticles in Crohn's disease and to assess their variations after infliximab therapy. We compared the levels of circulating microparticles in 38 patients with Crohn's disease, 16 patients with ulcerative colitis, 7 patients with infectious colitis, and 17 control subjects. The evolution of microparticle levels was assessed after infliximab therapy in 13 patients with Crohn's disease. Circulating microparticle levels were elevated in patients with Crohn's disease (9.31+/-0.66 nmol/L phosphatidylserine equivalent [PS Eq]) or infectious colitis (10.71+/-0.92 nmol/L PS Eq) compared to patients with ulcerative colitis (5.75+/-0.59 nmol/L PS Eq) and control subjects (4.06+/-0.37 nmol/L PS Eq) (P = 0.001). Infliximab induced a significant diminution of the amounts of circulating microparticles, from 10.33+/-1.20 to 6.45+/-0.90 nmol/L PS Eq (P = 0.002). Generation of circulating microparticles occurs in Crohn's disease; infliximab induces significant diminution. Release of microparticles could be linked to the type of inflammatory response underlying Crohn's disease.