同系大鼠骨髓间充质干细胞对同种异体胰岛刺激的T淋巴细胞的免疫调节作用

The immunoregulation of syngenic bone marrow mesenchymal stem cells on allogenic islets induced T lymphocytes

目的:研究同系大鼠骨髓间充质干细胞(Mesenchymal stem cell,MSC)对同种异体胰岛刺激的T淋巴细胞的免疫调节作用,以及对共培养胰岛胰岛素分泌的影响。方法:以Wistar大鼠胰岛作为刺激原,Lewis大鼠MSC及外周血T淋巴细胞作为共培养细胞,分为三组:实验组(A)20IEQ胰岛细胞、1×108 L-1 T淋巴细胞和1×107 L-1 MSCs共培养;药物对照组(B)20IEQ胰岛细胞与1×108 L-1 T淋巴细胞共培养并加入0.25μg/ml CsA;阳性对照组(C)20IEQ胰岛细胞与1×108 L-1 T淋巴细胞共培养。CCK-8检测共培养3天时T淋巴细胞对同种异体胰岛刺激的反应性,ELISA检测共培养3天时上清液IFN-γ、IL-2、IL-4和IL-10的含量,以及共培养胰岛的胰岛素分泌功能。结果:MSC与CsA均可抑制同种异体胰岛刺激的T淋巴细胞增殖,A组T淋巴细胞增殖率(17.10±2.7)%与B组(14.65±1.8)%间差异无统计学意义(P>0.05);C组IFN-γ、IL-2含量显著高于A组及B组,IL-10含量显著低于A及B组,差异有统计学意义(P<0.05);IL-4含量在A、B、C三组间差异均无统计学意义(P>0.05)。A组胰岛的胰岛素分泌水平显著高于B组和C组,差异有统计学意义(P<0.05);胰岛素刺激指数(2.37±0.52)显著高于B组(1.80±0.36),差异有统计学意义(P<0.05)。结论:MSC与CsA均可通过减少Th1类细胞因子的表达使受者Th1/Th2平衡向Th2方向偏移,抑制同种异体胰岛刺激的T淋巴细胞增殖。相对于CsA,MSC可以保持胰岛素高分泌水平和良好的糖刺激反应性,避免了CsA可能带来的毒性和副作用,具有一定的临床应用优势及前景。

Objective：To observe the immunoregulation of syngenic bone marrow mesenchymal stem cells（MSCs） on T lymphocytes,which induced by allogenic islets,and to further observe the influence on insulin secretion of islets.Methods：Isolated islets from Wistar rats as the stimulator.MSCs and T lymphocytes were isolated from Lewis rats.Experimental group（A）： the coculture system of 20IEQ islets,1×108 L-1 T lymphocytes and 1×107 L-1 MSCs;Drug group（B）： 20IEQ islets cocultured with 1×108 L-1 T lymphocytes then added 0.25 μg/ml CsA;the control group（C）： 20IEQ islets cocultured with 1×108 L-1 T lymphocytes.The proliferation of T lymphocytes was measured by CCK-8 assay on day 3.The concentration of IFN-γ,IL-2,IL-4 and IL-10 were detected by ELISA on day 3,as well as insulin.Results：Both MSC and CsA inhibited T lymphocytes proliferation,and there was no significant difference between group A（17.10±2.7）% and group B（14.65±1.8）%（P0.05）;the concentration of IFN-γ and IL-2 in group C was significantly higher than group A and B.IL-2,on the contrary,was lower in group C（P0.05）;there was no significant difference of IL-4 in group A,B and C（P0.05）;the concentration of insulin in group A was higher than group B and C（P0.05）;the stimulate index of insulin in group A（2.37±0.52）was higher than group B（1.80±0.36,P0.05）.Conclusion：MSC and CsA,due to the ability of changing cytokine secretion and affecting the balance of Th1/Th2 to Th2,reduced the proliferation of allogenic islets induced T lymphocytes.MSC could maintain a higher level of insulin secretion as well as insulin response to glucose,compared to CsA.