全反式维甲酸对于难治性ITP的疗效观察及其机理探讨

目的探讨加用全反式维甲酸ATRA对难治性特发性血小板减少性紫癜（RITP）的疗效及对患者外周血调节性T（CD4^＋CD25highT）细胞表达和辅助性T（Th）细胞因子的影响。方法应用流式细胞术测定28例RITP患者ATRA治疗前后及17例正常人外周血cD4^＋cD25^highT细胞的表达；ELISA法测定血清中转化生长因子β1（TGF—B1）、白介素（IL）-10、IL-4、IL-2、干扰素1（IFN-1）。结果ATRA对RITP的总有效率为53．6％，有效组治疗后患者外周血血小板计数达109．1±30．1×109／L，较治疗前明显升高（P〈0．01）；治疗有效组经ATRA治疗后CD4’CD25highT细胞阳性率及血清TGF—β1与IFN—γ水平高于治疗前（P〈0．05）；IL-4则明显低于治疗前（P〈0．05）；IL-2和IL-10治疗前后未见异常。结论ATRA对半数以上RITP患者有效，可能是通过提高调节性T细胞的表达，促进了RITP患者免疫紊乱向生理性平衡恢复。

Therapeutic Effect and Mechanism of All-trans-retinoic Acid Treatment in Refractory Idiopathic Thrombocytopenic Purpura

Objective To explore therapeutic effect of all-trans-retinoic acid （ATRA）treatment in refractory idiopathic thrombocytopenic purpura（RITP） and to investgate the alteration of peripheral blood CD 4 ＋ CD 25highT cell and serum cytokines after ATRA treatment. Methods The expression of peripheral blood CD 4 ＋ CD 25highT cells was detected by flow cytometry and the concentrations of serum transforming growth factor （TGF） - β1, interleukin （IL） - 10, IL-4, IL-2, interferon （IFN） -γwere detected by ELISA of 28 RITP patients before and after treatment and 17 normal individuals as controls. Results The overall response rates of ATRA treatment in RITP patients was 53.6% , the mean platelets count after treatment reached 109.1 ± 30.1 109/L, which was remarkable more than before（P 〈0. 01 ）. The expression of CD 4 ＋ CD 25highT cells in improved group after treatment was significantly higher than that before treatment（ P 〈 0.05 ） ;the concentrations of serum TGF-β1 and IFN--/in improved group were increased（P 〈0.05 ） ; while the concentration of serum IL-4 was decreased in the improved group after treatment（P 〈 0.05）. However, the concentrations of serum IL-10 and IL-2 were not changed during ATRA therapy period. Conclusion 53.6% of RITP patients were completely or partially recovered after ATRA treatment. ATRA may increase the expression of CD 4 ＋ CD 25high T cells in peripheral blood through TGF-β1, reduce the concentration of IL-4 and increase the concentration of IFN-＇y. All these effects would restore the physiologic balance from immune disturbance.