[Role of CD4(+) CD25(high) T cells in the pathogenesis of idiopathic thrombocytopenic purpura].

This study was aimed to investigate the expression level of CD4(+) CD25(high) T cells in peripheral blood of patients with idiopathic thrombocytopenic purpura (ITP) before and after treatment and to explore its significance in pathogenesis of ITP. The expressions of CD4(+) CD25(high) T cells in peripheral blood of 20 ITP patients before treatment, 20 ITP patients after treatment and 14 normal individuals (control) were detected by immunofluorescence and flow cytometry. The result showed that the expression of CD4(+) CD25(high) in ITP group before treatment was evidently lower than that in treated ITP group and control (p < 0.01), but there was no remarkable difference between the treated ITP group and the control group p > 0.05). In conclusion, the expression of CD4(+) CD25(high) T cells in the ITP group before treatment was evidently lower than that in the control group, which becomes higher than before when the patients showed effective response to the treatment. Correlation of CD4(+) CD25(high) T cell expression rate in peripheral blood with platelet level was positive. Therefore the expression level of CD4(+) CD25(high) T cells can be used as an effective index to judge the ITP prognosis. Further study of CD4(+) CD25(high) T cells regarded as an immune target is needed.