中文摘要：

目的探讨再生障碍性贫血（aplastic anemia,AA）患者骨髓间充质干细胞（bone marrow mesenchymal stem cells,BM-MSCs）对正常CD4-细胞功能的影响。方法采集和分离15例AA患者和10例正常人BM-MSCs进行体外培养。倒置显微镜结合荧光共聚焦显微镜观察BM-MSCs的形态和生长情况,流式细胞术检测免疫表型,诱导BM-MSCs成骨和成脂,综合进行BM-MSCs鉴定。BM-MSCs与免疫磁珠负集的外周血CD4-细胞共培养观察其对CD4-细胞功能的影响,采用倒置显微镜和BrdU方法分析CD4-细胞的克隆形成和增殖能力,酶联免疫吸附实验（ELISA）检测CD4-细胞分泌的细胞因子水平。结果正常人和AA患者骨髓间充质干细胞均呈长梭形,辐射状或旋涡状贴壁生长;诱导后均向成骨细胞和脂肪细胞分化;均表达CD105、CD73、CD90、CD29、CD44、CD49e、CD166、CD13和HLA-ABC,不表达CD34、CD45和HLA-DR。与正常对照组比较,AA患者BM-MSCs抑制CD4-细胞克隆形成和增殖能力减弱（P〈0.05）。同时,AA患者BM-MSCs抑制CD4-细胞分泌肿瘤坏死因子α（TNF-α）和干扰素γ（IFN-γ）的能力明显低于正常对照组（P〈0.05）。结论 AA患者骨髓间充质干细胞在调节CD4-细胞免疫功能方面存在缺陷,可能进一步加重骨髓免疫损伤。

英文摘要：

Objective To investigate the influence of bone marrow mesenchymal stem cells（BM-MSCs）from aplastic anemia（AA）patients on CD4-cells function.Methods Both BM-MSCs from AA patients and healthy controls were isolated and cultured.The cells were identified by the morphology,immunophenotype markers and multiple differentiation capacities using flow cytometry,fluorescence confocal microscopy and immunoassay.Then,BM-MSCs were co-cultured with peripheral blood-derived CD4-cells to investigate the influence on CD4-cells function and secreted cytokines using enzyme-linked-immunosorbent assay（ELISA）.Results BM-MSCs from AA patients and healthy controls both expressed CD105,CD73,CD90,CD29,CD44,CD49e,CD166,CD13 and HLA-ABC,but lack of expressing CD34,CD45 and HLA-DR.They also formed a monolayer of bipolar spindle-like cells with a whirlpool-like array and differentiated into adipocytes and osteoblasts.However,BM-MSCs from AA patients were defected in suppressing the clonogenic and proliferation potential of CD4-cells（P0.05）.Meanwhile,BM-MSCs from AA patients were decreased in suppressing the production of tumor necrosis factor-α（TNF-α）and interferon-γ（IFN-γ）by CD4-cells（P0.05）.Conclusion BM-MSCs from AA patients were defective in maintaining the immune homeostasis associated with CD4-T cells,which might further aggravate the marrow failure.