抗体介导的排斥反应（AMR）是导致移植肾失功的最主要原因，但目前治疗标准不明确，副作用大，缺乏更加精准的治疗手段。我们前期研究表明，人脐带血MSC对小鼠肾移植后体液性排斥有确切的治疗效果。临床试验显示，人脐带血MSC安全性好，能显著保护肾小管内皮细胞的完整性，但是进入移植肾内的MSC数量较少，影响了治疗效果。既往研究提示缺血再灌注部位VCAM-1表达升高，抗VCAM-1抗体能有效降低该部位炎症细胞浸润和组织损伤。因此，本课题拟通过构建负载抗VCAM-1抗体的人脐带血MSC，在小鼠肾移植排斥模型中，诱导MSC靶向聚集于移植肾部位，实现抗VCAM-1抗体与MSC对肾移植术后AMR的双重治疗作用。同时，通过负载的叠氮显像物质，实现体内实时显像，明确MSC在移植肾内的分布和代谢规律。本课题将为了解MSC在肾移植中作用机制和变化过程，精准治疗移植肾术后AMR提供思路。

Antibody-mediated rejection (AMR) is the main cause of renal allograft loss after transplantation, which is lack of accurate treatment with fewer side effects. Our studies showed that umbilical-cord-derived MSC exerted positive effect on AMR. The preventive effect of MSC on renal tubular epithelial cell was also demonstrated in our clinical trial. However, treatment effect was limited because of the small number of MSC in transplanted kidney. Previous study found high expression of VCAM-1 was related with inflammatory cell infiltration and tissue injury in the post-ischemic kidney, which could be reversed by blockade of VCAM-1.Hence, targeted MSC loaded with anti-VCAM-1 antibody will be constructed in our study, and be used to achieve in vivo targeted and dual treatment of AMR in mouse kidney transplantation model. Additionally, distribution and metabolic mechanism of MSC in transplanted kidney will analyzed by fluorescence real-time imaging. The study will provide a new method for accurate treatment of AMR based on targeted effect mechanism of MSC loaded with anti-VCAM-1 antibody in transplanted kidney.