脂肪来源间充质干细胞调控原发免疫性血小板减少症小鼠Th细胞因子失衡

Immunoregulation of Adipose-derived Mesenchymal Stem Cells on Th Cytokines in Primary Immune Thrombocytopenic Mice

【目的】探讨脂肪来源的间充质干细胞(AMSCs)对原发免疫性血小板减少症(ITP)小鼠Th细胞因子失衡免疫调节变化及其特异性转录因子T盒子转录因子/GATA结合蛋白3(T-bet/GATA-3)的影响,并初步探讨其相关机制。【方法】选取人来源健康脂肪组织,分离培养AMSCs,观察生长形态和干细胞鉴定,选取增长稳定的传代AMSCs;将30只BALB/c小鼠随机分为正常对照组(Normal组)、ITP对照组(ITP/PBS组)及ITP实验组(ITP/AMSC组)并进行相应的处理,观察AMSCs对ITP实验组小鼠的治疗作用,Th1/Th2细胞因子及特异性转录因子表达变化,并进行对比分析。【结果】①获取的AMSCs增殖稳定,细胞表面抗原分子CD29、CD44及CD105高表达,CD14及CD45低表达,并鉴定具有多向分化能力,符合AMSCs细胞学特征。②通过AMSCs治疗,ITP实验组小鼠皮肤出血瘀斑明显改善,其血小板水平、Th2细胞转录因子GATA-3 mRNA表达及Th2因子IL-4及IL-10水平高于ITP对照组,同时Th1细胞转录因子T-bet mRNA及Th1因子IL-2、IFN-γ表达下降(均P<0.001)。【结论】ITP小鼠存在Th1/Th2细胞因子免疫失衡,以Th1细胞因子占主导的自身免疫性疾病,AMSCs可能通过对Th细胞的T-bet/GATA-3的转录调控,减少Th1因子分泌、增加Th2因子分泌,改善ITP免疫失衡,提高血小板水平。

【Objective】To explore the effects and the related mechanisms of AMSCs on Th cytokines and its specific transcription factors T-bet/GATA-3 in mice with ITP.【Methods】Healthy adipose tissues from human selected aforehand were used for isolation and culture of AMSCs.Then its growth morphology and stem-cell identification were observed,and the AMSCs with a stable growth situation were selected for next step test.Thirty BALB/c mice were randomly divided into the normal control group(Normal group),ITP control group(ITP/PBS group)and ITP experimental group(ITP/AMSC group),and treated accordingly to observe the therapeutic effect of AMSCs on ITP mice.The expressions of Th1/Th2 cyto⁃kines and the specific transcription factors were analyzed.【Results】①The obtained AMSCs proliferated stably with high expression of cell surface antigen molecules of CD29,CD44 and CD105,and low expression of CD14 and CD45.And the AMSCs were identified to have multidirectional differentiation ability,which was consistent with the cytological character⁃istics of AMSCs.②After AMSCs treatment,skin bleeding of ITP mice was significantly alleviated,and the platelet level,Th2 transcription factor GATA-3 mRNA expression and Th2 factors IL-4 and IL-10 levels were higher than those in the ITP control group.At the same time,the expression of Th1 transcription factor T-bet mRNA and Th1 factors IL-2 and IFN-γin the ITP experimental group decreased(all P<0.001).【Conclusions】There is the immune imbalance of Th1/Th2 cytokines in ITP mice.As a autoimmune disease and dominated by Th1 cytokines for ITP,AMSCs could reduce Th1 cytokines secretion and increase Th2 cytokines secretion by regulating T-bet/GATA-3,thus redressing the immune imbalance of ITP and improving platelet level.