ELEVATED LEVELS OF IL-2 AND IL-21 PRODUCED BY CD4+ T CELLS IN INFLAMMATORY BOWEL DISEASE

CD4(+) T cells are considered as a subset of cells that play a pivotal role in the development of inflammatory bowel disease (IBD). The aim of this study was to assess the levels of interleukin (IL)-2, IL-21 and their receptors produced by CD4(+) T cells in patients with inflammatory bowel disease. Thirty-two patients with ulcerative colitis (UC) and mean age of 37.93 +/- 10.37 years, as well as 22 patients with Crohn's disease (CD) and mean age of 37.04 +/- 10.44 years, were studied. The healthy controls (HC) included 31 subjects with a mean age of 36.7 +/- 10.48 years. Peripheral blood mononuclear cells (PBMCs) were isolated from all the participants. The CD4(+) T cells were isolated and the expression of IL-2 and IL-21 and also their receptors were examined by flow cytometry. The level of cells was significantly increased in UC patients compared with HC (40.71 +/- 6.04 vs 37.24 +/- 6.54, respectively, p=0.04). The level of IL-21(+) cells was also significantly elevated in CD patients compared with HC (4.44 +/- 1 vs 3.83 +/- 0.74, respectively, p=0.02). Furthermore, we found a significant positive correlation between clinical activity index (CM) and IL-21(+) cells. According to the results, we hypothesize that the elevated level of IL-2(+) and IL-21(+) T cells and a positive correlation between IL-21(+) cells with CM in UC patients may contribute to the pathogenesis of disease. Moreover, the assessment of cells producing such cytokines constitutes a potential diagnostic and therapeutic strategy for IBD.