肝细胞外泌体miR-29a-3p通过调控Treg和Breg分化在肝移植急性排斥中的作用及机制

肝移植术后排斥严重影响患者生存，目前调控Treg和Breg分化已成为减轻肝移植排斥的热点。前期基因芯片检测发现急性排斥与未排斥者血清外泌体miR-29a-3p存在差异，且外泌体miR-29a-3p的量与Treg和Breg均呈负相关，肝移植急性排斥大鼠血清外泌体富含miR-29a-3p，将该外泌体与T和B细胞共培养，可抑制Treg和Breg分化，并证实该外泌体是由损伤肝细胞分泌。为此提出假说：移植肝中损伤肝细胞释放富含miR-29a-3p的外泌体通过miR-29a-3p/SMAD6和miR-29a-3p/NFAT5分别抑制Treg和Breg分化，促进急性排斥发生。本项目建立大鼠肝移植模型，采用流式细胞仪、质粒转染等手段，从分子、细胞、动物模型等方面研究，明确外泌体miR-29a-3p调控Treg和Breg分化及功能，影响急性排斥发生及机制。项目成功实施将为减轻肝移植急性排斥的发生提供新策略。

The rejection after liver transplantation seriously affects the survival of patients, and the regulation of Treg and Breg differentiation has become a hot spot to reduce the rejection of liver transplantation. Previous gene chip detection found that there was a difference between serum exosomal miR-29a-3p in patients with acute rejection and non-rejection, and that the exosomal miR-29a-3p levels were negatively correlated with Treg and Breg. The serum exosomes were extracted from rats with acute rejection and cultured with T and B cells, which significantly inhibited Treg and Breg differentiation. It has also been confirmed that miR-29a-3p-enriched exosomes are secreted by damaged hepatocytes. We hypothesized that the damaged hepatocytes in transplanted liver released miR-29a-3p-enriched exosomes, which inhibited Treg and Breg differentiation through miR-29a-3p/SMAD6 and miR-29a-3p/NFAT5, respectively, and that promoted acute rejection. This project establishes a rat liver transplant model, using flow cytometer, plasmid transfection and other means, from molecular, cell, animal model and other aspects of research, to clarify the exosomal miR-29a-3p regulates Treg and Breg differentiation and function, affecting the occurrence of acute rejection. The successful implementation of the project will provide a new strategy to reduce the occurrence of acute rejection of liver transplantation.