原发性胆汁性肝硬化（PBC）是一种器官特异性自身免疫病，发病机制不明且缺乏有效的治疗方法。间充质干细胞（MSCs）具有免疫调节、组织修复等生物学特性，已应用于临床治疗多种自身免疫病。我们前期研究发现PBC患者外周血CD4+CD25+调节性T细胞（Treg）比例下降，且与血清炎症因子IFN-γ等呈显著负相关，异体骨髓MSCs移植治疗polyI:C诱导的PBC动物模型有效，通过免疫调节发挥治疗作用。本课题拟进一步系统研究PBC肝脏局部及全身免疫异常、PBC骨髓MSCs功能异常，并通过观察异体MSCs移植治疗PBC动物模型及患者的疗效，深入探讨治疗机制，为异体MSCs应用于临床治疗PBC患者奠定理论基础。

Primary biliary cirrhosis (PBC) is an organ-specific autoimmune disease with unknown etiology and lack of effective treatment. Mesenchymal stem cells (MSCs) have immuno-regulatory and tissue repair properties, and have been used for treating many autoimmune diseases. We have demonstrated that peripheral CD4+CD25+ regulatory T cells percentage decreased in PBC patients and was negatively correlated with serum inflammatory factors like IFN-γ. Moreover, allogeneic MSCs transplantation was effective in treating polyI:C induced PBC models, which was mediated by immune-regulation. In the current study, we will determine the local and systemic immune abnormalities in PBC, as well as the functional defect of PBC bone marrow derived MSCs. Here we will illustrate the effect of allogeneic MSCs in treating PBC animal models as well as patients, and further to examine the therapeutic mechanisms. The conclusion of this study may provide deep insight in understanding the effect and mechanism of allogeneic MSCs in treating human PBC.