脐带组织源间充质干细胞调控ITP患者脾细胞释放抗血小板抗体的体外研究

Mesenchymal Stem Cells Derived from Human Umbilical Cord Tissue Modulate the Secretion of Antiplatelet Antibody from Splenocytes of ITP Patients In Vitro

为了探讨脐带组织来源的间充质干细胞(UC-MSC)免疫治疗特发性血小板减少性紫癜(ITP)的临床应用可能性,体外建立UC-MSC与ITP脾切除患者的脾脏单个核细胞共培养体系,用酶联免疫吸附试验(ELISA)法检测共培养上清液中IgG型抗血小板抗体(PAIgG)含量的变化。同时,用Brdu法研究UC-MSC对其中部分ITP患者血小板反应性T辅助淋巴细胞增殖的调节作用。结果表明,UC-MSC在体外试验中可刺激ITP患者脾细胞自发性释放PAIgG;UC-MSC在低剂量时(1∶100)抑制血小板诱导释放PAIgG;在高剂量(1:10)转为刺激作用。另外,UC-MSC还能抑制血小板反应性T辅助细胞的增殖,并呈一定的量效关系。结论:UC-MSC可体外影响ITP患者释放PAIgG,具体调控机制及临床应用价值有待深入研究。

The study was aimed to investigate the potential immunotherapeutical values of umbilical cord tissuederived mesenchymal stem cells （UC-MSC） on patients with chronic idiopathic thrombocytopenic purpura （ITP）. UCMSC was cocultured in vitro with splenocytes isolated from ITP patients who experienced splenectomy. The level of IgG antiplatelet antibody（PAIgG） was determined by a competitive micro-enzyme-linked immunosorbent assay （ELISA） method. The proliferation of platelet-reactive CD4 ^＋ T lymphocytes was also measured in the presence of UC-MSCs. The results showed that UC-MSCs could stimulate the spontaneous secretion of PAIgG in supematants; In the plateletinducing condition, UC-MSC inhibited the production of PAIgG at a low ratio of 1 UC-MSC to 100 splenocytes, but promoted at a high proportion of 1 UC-MSC to 10 splenocytes. Moreover, UC-MSC exerted a suppressive effect on proliferation of platelet-reactive T helper cells in a dose-dependent manner. It is concluded that the UC-MSCs can regulate secretion of antiplatelet antibodies in vitro. Its concrete regulation mechanism and potential immunotherapeutical value are need to further study.