骨髓间质干细胞对系统性红斑狼疮患者调节性T细胞的免疫调节作用

目的探讨自体与异体骨髓间质干细胞（MSCs）对系统性红斑狼疮（SLE）患者调节性T细胞的免疫调节作用。方法用Percoll密度梯度离心法从14例SLE患者和15例健康人骨髓中分离MSCs,同时用免疫磁珠（MACS）分离SLE患者外周血CD4^＋CD25^＋T细胞。将SLE患者外周血分离的淋巴细胞或CD4^＋CD25^＋T细胞与自体、异体MSCs共培养,观察MSCs对淋巴细胞及CD4^＋CD未T细胞增殖的影响,同时测CD4^＋CD25^＋T细胞分泌IL-10、转化生长因子（TGFβ）水平及细胞毒T淋巴细胞相关抗原4（CTLA-4）表达。结果自体与异体MSCs均抑制淋巴细胞增殖,其抑制率分别为56．32％、65．46％。MSCs以数量依赖性方式促进纯化CD4^＋CD25^＋T细胞增殖,分泌IL-10、TGFβ水平升高。结论MSCs可纠正SLE活动时CD4＋CD25^＋T细胞免疫缺陷,并抑制淋巴细胞过度活化,可能在自身免疫病的外周血造血干细胞和间质干细胞共移植或MSCs单独移植中发挥重要的免疫调节作用。

Immunoregulatory effect of bone marrow mesenchymal stem cells on regulatory T cells in patients with systemic lupus erythematosis

OBJECTIVE: To study the in vitro modulation of autogeneic and allogenic regulatory T lymphocytes proliferation by bone marrow mesenchymal stem cells (MSCs) in patients with systemic lupus erythematosis (SLE). METHODS: Human MSCs were separated with Percoll (1.073 g/ml) from bone marrow of patients with SLE or healthy subjects. The purity of MSCs was identified with the phenotypes by fluorescence actived cell sorter (FACS). The subset regulatory T cells in the peripheral blood of patients with SLE were isolated with magnetic activated cell sorting (MACS) CD4 and CD25 microbeads. Lymphocytes or CD4+ CD25+ T cells isolated from the peripheral blood of SLE patients were cocultured either with autologous MSCs or MSCs from healty donors. The proliferation activities of lymphocytes and CD4+ CD25+ T cells were investigated with methyl thiazolyl tetrazolium( MTr) test. The level of IL-10 and transforming growth factor beta (TGFbeta) was determined with enzyme-linked immunosorbent assay (ELISA). RESULTS: The lymphocyte activity in SLE was suppressed by autogeneic and allogeneic MSCs and the inhibition rate was 56.32% and 65.46%, respectively. A stronger immunosuppressive effect of allogeneic MSCs was detected. MSCs were capable of increasing the proportion of allogeneic and autogeneic regulatory T cells in a dose dependent fashion. MSCs stimulated CD4+ CD25+ T cells to produce IL-10 and TGFbeta. CONCLUSION: MSCs can suppress lymphocyte proliferation and increase CD4+ CD25+ T cells. MSCs might play important roles in immunosuppressant lymphocyte proliferation and be important to cooperate with autogeneic hematopoietic stem cells in transplantation.