多发性骨髓瘤患者骨髓间充质干细胞免疫调节功能异常及其在骨髓瘤骨病中的作用

Impairment in immunoregulatory capability of mesenchymal stem cells from multiple myeloma patients and role of it in the pathogenesis of myeloma bone disease

目的 探讨多发性骨髓瘤（MM）患者骨髓间充质干细胞（MSCs）免疫调节功能及其对骨髓瘤骨病的影响.方法 分离MM患者和正常对照MSCs,流式细胞技术比较二者的免疫表型.Real-time PCR检测实验组及对照组MSCs的TGF-β1、TGF-β2、TGF-β3、IL-6、IL-3、TNF-α、FasL和NF-κB配体的受体激活物（RANKL）表达量.共培养系统与流式细胞术检测MSCs对T细胞增殖、凋亡和早期活化标志CD25和CD69表达的影响.Von kossa染色、real-time PCR和Western blot等技术检测T细胞对正常对照MSCs向成骨细胞分化的影响.结果 MM来源和正常对照MSCs具有相似的形态学和免疫表型.MM来源的MSCs表达TGF-β1、IL-6、IL-3、TNF-α和RANKL较正常对照MSCs增加,而TGF-β2、TGF-β3和FasL的表达下降.MM来源的MSCs对T细胞增殖的抑制作用明显减弱.正常对照MSCs较MM来源MSCs使更多T细胞静止于G0/G1期.正常对照MSCs明显促进T细胞凋亡,而MM来源的MSCs对T细胞的促凋亡作用减弱.正常对照MSCs明显抑制T细胞活化分子表达,而MM患者的MSCs此抑制作用明显降低.与MM患者的MSCs共培养后的T细胞以及直接来源于MM患者的T细胞均可以明显抑制正常对照MSCs向成骨细胞分化.结论 MM患者的MSCs免疫调节功能较正常对照MSCs降低,主要表现为抑制T细胞活化的功能减弱,而活化的T细胞可抑制MSCs向成骨细胞分化,此可能为骨髓瘤骨病发病机制之一.

Objective To deplore the immunoregulatory function changes of mesenchymal stem cells（MSCs）from multiple myeloma（MM）patients and its effects on the pathogenesis of myeloma bone disease.Methods MSCs from MM patients and normal controls were isolated and the immunophenotype was detected.Real-time PCR was performed to detect the expressions of TGF-β1,TGF-β2,TGF-β3,IL-6,IL3,TNF-α,FasL and RANKL of MSCs.Transwell coculture systems were performed between MSCs and T cells.Lymphocyte proliferative assay was employed to detect the effect of MSCs on T cell proliferation.The effect of MSCs on T cell cycle and T cell activation markers CD25 and CD69 expression were analyzed by flow cytometry.Cleaved caspase 3 protein by western blot and hoechst 33258 staining were employed to detect the apotosis of T cells.Influence of T cells on the osteogenesis potential of MSCs were detected by Von kossa stain,real-time PCR and Western blot.Results MSCs from both MM patients and normal controls possessed similar morphology and immunophenotypes.MM derived MSCs exhibited increased expressions of TGF-β1,IL-6,IL-3,TNF-α and RANKL and decreased expression of TGF-β2,TGF-β3 and FasL.The inhibitory effect of MM derived MSCs on T cell proliferative ability was attenuated compared to control MSCs.MSCs from normal controls silence more T cells in Go/G1 phase than those from MM patients.The daupening effect of MM derived MSCs on activation-induced T apoptosis seemed to be enhanced.Expression of T cell activation markers were significantly inhibited by MSCs from normal controls.Both T cells cocultured with MM deprived MSCs and T cells directly from MM patients inhibited osteogenesis potential of MSCs from normal controls.Conclusion MSCs from MM patients showed impaired immunoregulatory capability on T cells.The activated T cells,in turn,inhibited the osteogenesis potential of MSCs.This may participate in the pathogenesis of myeloma bone disease.