Expression and significance of CD4+CD25+regulatory T cells and Th17 cells in idiopathic thrombocytopenic purpura

Objective To further investigate and verify the expression of CD4+CD25+regulatory T cells and Th17 cells,and their roles in idiopathic thrombocytopenic purpura(ITP). Methods There were 41 ITP patients were enrolled by the diagnostic criteria for ITP.The control group consisted of 41 healthy person.All specimens were morning fasting peripheral blood.The percentage of CD4+CD25+regulatory T cells and Th17 cells in the peripheral blood from patients and controls were examined with flow cytometric.ELISA was used to detect the plasma level of IL-17.Results The percentage of CD4+CD25+regulatory T cells in the peripheral blood of ITP patients was lower than the normal controls(P0.05),and significantly lower in refractory ITP patients,but there was no statistical difference between primary ITP patients and recurrent ITP patients(P0.05).After treatment,the percentage of CD4+CD25+Treg cells in the peripheral blood of primary ITP patients was higher than before(P0.05),but still lower than the normal controls(P0.05).The percentage of Th17 cells in ITP patients was markedly higher than that of the normal controls(P0.05).The plasma level of IL-17 was insignificantly changed between ITP patients and the normal controls(P0.05).Treg/Th17 of ITP patients was significantly lower than the normal controls(P0.05).Conclusion The reduction of CD4+CD25+Treg cells and the increase of Th17 cells do exist in the peripheral blood of ITP patients and lead to a loss of balance of Treg/Th17,that may play an important role in the pathogenesis and development of ITP.The degrees of CD4+CD25+Treg cells in the peripheral blood between the first-treated and relapsed ITP patients are not significant.Refractory ITP cases may be correlated with the low expression of CD4+CD25+Treg cells and the uncorrected imbalance of Treg/Th17.Clinical routine treatment could increase the CD4+CD25+Treg cells rate in the peripheral blood of ITP patients.