Changes and mechanisms of Th9, Th17 and CD4+CD25+Foxp3+ regulatory T cells in the develop-ment of adult primary immune thrombocytopenia / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the expression and significance of Th9, Th17 and CD4+CD25+Foxp3+regulatory T (Treg) cells as well as the related cytokines (IL-9, IL-17, TGF-β) in peripheral blood of patients with adult primary immune thrombocytopenia ( ITP) . Methods Peripheral blood samples were collected from 47 patients with ITP and 39 age-and sex-matched healthy subjects. The percentages of Th9, Th17 and CD4+CD25+Foxp3+Treg cells in peripheral blood samples were detected with flow cytometry. The levels of IL-9, IL-17 and TGF-βin serum samples were detected by enzyme linked immunosorbent assay ( ELISA) . Results Compared with healthy subjects, the percentages of Th9 and Thl7 cells and the concen-trations of IL-9 and IL-17 in patients with ITP were significantly increased [(1. 27±0. 31)% vs (0. 71± 0. 26)%, P<0. 05;(2. 01±0. 42)% vs (0. 97±0. 32)%, P<0. 05. (26. 52±7. 48) ng/L vs (16. 16± 5. 27) ng/L, P<0. 05;(10. 97±3. 94) ng/L vs (7. 14±2. 73) ng/L, P<0. 05]. The percentages of CD4+CD25+Foxp3+ Treg cells and the concentrations of TGF-β in patients with ITP were lower than those in healthy subjects [(4. 69±0. 85)% vs (7. 16±1. 92)%, P<0. 05. (3. 76±1. 28) μg/L vs (6. 41±1. 83)μg/L, P<0. 05]. Moreover, the blood platelet counts in patients with ITP were negatively correlated with the percentages of Th9 and Th17 cells and the concentrations of IL-9 and IL-17 (γs=-0. 349, P=0. 037;γs=-0. 392, P=0. 031;γs=-0. 436, P=0. 014;γs=-0. 401, P=0. 027), but were positively correlated with the percentages of CD4+CD25+Foxp3+ Treg cells and the concentrations of TGF-β (γs=0. 411, P=0. 024;γs=0. 407, P=0. 026). Conclusion The imbalanced distribution of Th9, Th17 and Treg cells and the abnormal expression of related cytokines (IL-9, IL-17 and TGF-β) in patients with ITP might be the possible immunological pathogenesis of ITP.