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

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。

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

The study was aimed to investigate the potential immunotherapeutical values of umbilical cord tissue-derived mesenchymal stem cells(UC-MSC) on patients with chronic idiopathic thrombocytopenic purpura(ITP).UC-MSC 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 supernatants;In the platelet-inducing 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.