白细胞分化抗原74和CXC趋化因子配体9阳性巨噬细胞亚群在大鼠肝移植排斥反应中的作用

Changes and role of CD74 and CXCL9 positive macrophage subsets in rejection of rat liver transplantation

目的探讨在肝移植排斥反应中巨噬细胞亚群分类及变化。方法建立大鼠肝移植模型分为:免疫耐受组(B-B),将BN大鼠供体的肝脏移植至BN大鼠受体;免疫排斥组(L-B),将Lewis大鼠供体的肝脏移植至BN大鼠受体,使用单细胞RNA测序和高通量RNA测序区分大鼠移植肝巨噬细胞亚群,发现排斥反应高度差异的基因,免疫组化确定蛋白表达和细胞亚群的变化和分布。结果CD68阳性巨噬细胞在排斥组多于耐受组(P<0.05),巨噬细胞可分为9个亚群,排斥反应中巨噬细胞第8群的CXC趋化因子配体9(CXCL9)明显升高,第5群的白细胞分化抗原74(CD74)基因明显升高(P<0.05)。排斥反应中巨噬细胞差异基因综合第1位的是CD74,第2位是CXCL9。与耐受组比较,排斥组肝脏汇管区可见大量CD74阳性巨噬细胞浸润,并且在肝血窦CD74阳性巨噬细胞浸润也明显增加(P<0.05),在排斥肝脏汇管区和肝血窦可见大量CXCL9阳性巨噬细胞浸润以汇管区为著(P<0.05),在排斥肝脏汇管区CD14阳性细胞明显增加(P<0.05)。结论在肝移植排斥反应中CD74阳性巨噬细胞亚群和CXCL9阳性巨噬细胞亚群是促进肝移植排斥反应中的关键亚群,完善了巨噬细胞在肝移植排斥反应中作用机制。

Objective To explore the classification and changes of macrophage subsets in liver transplant rejection.Methods Rat liver transplantation model were established and divided into immune tolerance group(B-B),where the liver of BN rat donors was transplanted to BN rat recipients,and immune rejection group(L-B),in which the liver of Lewis rat donors was transplanted to BN rat recipients.Single-cell RNA sequencing and highthroughput RNA sequencing were used to distinguish the macrophage subsets of rat liver transplantation,and to find differential gene in rejection reactions.Immunohistochemistry was used to determine the changes and distribu⁃tion of protein expression and cell subsets.Results CD68 positive macrophages were higher in the rejection group than that in the tolerance group(P<0.05),and macrophages could be divided into 9 subsets.During the rejection reaction,the CXC chemokine ligand 9(CXCL9)in the 8th subsets of macrophages was significantly increased,while the gene for white blood cell differentiation antigen 74(CD74)in the 5th subsets was significantly increased(P<0.05).CD74 ranked first in the differential gene synthesis of macrophages during rejection,followed by CXCL9.Compared with the tolerance group,a large number of CD74 positive macrophages were observed in the hepatic portal area of the rejection group,and the infiltration of CD74 positive macrophages in the hepatic sinuses was also significantly increased(P<0.05),while a large number of CXCL9 positive macrophages were observed in the hepatic portal area and hepatic sinuses of the rejection group,especially in the portal area(P<0.05),and CD14 positive cells were significantly increased(P<0.05).Conclusions The CD74 positive macrophage subsets and CXCL9 positive macrophage subsets may be key subgroups in promoting liver transplant rejection,improving the mechanism of macrophage action in liver transplant rejection.