Administration of anti-tumor necrosis factor antibody (anti-TNF, infliximab) down-regulates T helper 1 (Th 1) cytokines production in intestinal mucosa of patients with Crohn´s disease (CD). Interleukin 10 (IL-10) is thought to be involved in CD pathogenesis through regulation of the Th 1 response. The aim of this study was to determine the IL-10 response in CD patients treated with anti-TNF. Fourteen patients with active CD received 5 mg/kg of infliximab; clinical activity assessed by Crohn´s Disease Activity Index (CDAI), α1-acid glycoprotein and serum IL-10 were determined before and after treatment, in month 0, 1 and 5. In the group with a good clinical response, IL-10 levels diminished significantly in month 1 (p<0.05) and remained decreased in month 5. The group with a lower response showed a significant increase in IL-10 levels in month 1 (p<0.05). α1-acid glycoprotein levels obtained before treatment were significantly elevated in the group with a good clinical response (p<0.05) and a significant decrease in month 1 was observed in this group (p<0.05). These observations suggest that a pattern of IL-10 response might be related to the clinical response to anti-TNF treatment in CD., Z. Detková, V. Kupčová, M. Príkazská, L. Turecký, S. Weissová, E. Jahnová., and Obsahuje bibliografii