脐带间充质干细胞（UC-MSCs）在类风湿关节炎（RA）治疗中的潜在意义越来越受到关注，但其对RA效应细胞的免疫调控机制尚不清楚，大大限制了其临床应用。我们的前期研究发现，UC-MSCs高表达Galectin-1，因Galectin-1是一种免疫反应的负调控蛋白，因此我们推测UC-MSCs可能通过高表达Galectin-1来抑制RA效应细胞的增殖、活化，从而达到治疗的作用。本研究将系统探讨UC-MSCs调控RA患者T细胞及成纤维细胞样滑膜细胞（FLS）的作用及其可能通过Galectin-1发挥作用的分子机制；通过改变UC-MSCs中Galectin-1的表达，进一步探讨Galectin-1在UC-MSCs治疗CIA小鼠中的作用。该研究将为UC-MSCs调控RA效应细胞的分子机制及其临床应用提供理论和实验依据。。

The therapeutic potential of umbilical cord mesenchymal stem cells (UC-MSCs) in rheumatoid arthritis (RA) has attracted more and more attention, but the uncovered regulatory mechanism of UC-MSCs on RA effector cells greatly limits its clinical application. Our previous study showed Galectin-1 is highly expressed in UC- MSCs.Since Galectin-1 is an immune negative regulator, we hypothesize that UC-MSCs may inhibit RA effector cells through upregulation of Galectin-1. In this study, we will further investigate the potential effects of UC-MSCs on RA T cells and fibroblast-like synovial cells (FLS)through Galectin-1 dependent pathway. We will aslo study the signficance of Galectin-1 in UC-MSCs-based treatment by using CIA mouse model. Our study will provide more theoretical and experimental data for further understanding of the regulatory basis of RA effector cells by UC-MSCs.