Macrophages in transplant rejection

Transplant rejection is one of the primary factors leading to loss of allograft function, and macrophages are involved in allograft rejection. Macrophages polarize into different phenotypes according to stimulation by different external factors. Different types of macrophages play distinct roles in inflammation, tumors, and autoimmune diseases and are involved in transplant rejection. In this review, we introduce the origin and migration of macrophages, outline the classification of macrophages and their polarization mechanisms, and review the currently understood mechanisms of their involvement in transplant rejection. Finally, we discuss the regulation of macrophage polarization and miRNA expression with respect to transplant rejection, which is important for the development of new anti-rejection therapies.     

ADAM17调控CGRP对血管紧张素Ⅱ诱导的血管平滑肌细胞增殖的抑制效应

目的阐明肿瘤坏死因子α转化酶(ADAM17)调控降钙素基因相关肽(CGRP)的抗血管平滑肌细胞(VSMC)增殖效应。方法以大鼠源性胸主动脉平滑肌细胞株(A10VSMC)为研究对象,采用RNA干扰抑制ADAM17表达;采用蛋白质免疫印迹和实时定量PCR检测蛋白和mRNA表达水平;采用噻唑蓝比色法评估细胞活性。结果 CGRP显著抑制血管紧张素Ⅱ介导的VSMC增殖。血管紧张素Ⅱ刺激24 h后,VSMC中ADAM17表达显著增加。CGRP预处理30 min能显著降低VSMC中ADAM17表达,而CGRP受体拮抗剂CGRP8-37可抑制或逆转上述效应。ADAM17 RNA干扰可显著抑制血管紧张素Ⅱ介导的VSMC增殖。结论降低ADAM17表达可能是CGRP抑制血管紧张素Ⅱ介导的VSMC增殖效应的机制。     

4-vinylcyclohexene diepoxide induces apoptosis by excessive reactive oxygen species and DNA damage in human ovarian granulosa cells

4-Vinylcyclohexene diepoxide (VCD) is a hazardous industrial material which is widely used in the production of fragrances, rubber tires, antioxidants, pesticides, flame retardants and plasticizers. Previous studies have shown that exposure to VCD damages the female reproductive system, but the effects and mechanisms of VCD exposure on human granulosa cells are not reported. In this study, we used a human granulosa cell line (SVOG) to explore the effects of VCD exposure and found that VCD exposure had toxic effects on SVOG cells in vitro. VCD exposure led to excessive accumulation of intracellular ROS, caused DNA damage in cells, altered the expression of some key genes related with apoptosis and oxidative stress, and ultimately inhibited the proliferative capacity of granulosa cells, resulting in increased apoptosis. Overall, our findings provide solid evidence showing that VCD exposure produces severe damage to human granulosa cells, which is helpful for understanding the reproductive toxicity of VCD and etiology of infertility.     

中药苦参水提取物抑制Th17细胞分化的研究

目的探讨苦参水提取物(Sophora flavescens aqueous extract,SFAE)对Th17细胞分化的影响。方法通过体外分离豚鼠淋巴结获取原代淋巴细胞,采用磁珠分选技术获得初始CD4^+T细胞。采用CCK-8法筛选SFAE对T细胞活力的最佳抑制浓度。通过白细胞介素-6(IL-6)和转化生长因子-β(TGF-β)诱导建立初始CD4^+T细胞向Th17细胞分化的细胞模型,并以SFAE进行干预;采用流式细胞仪检测各组Th17细胞比例,采用qRT-PCR及Western Blot法检测各组细胞中视黄酸相关的孤儿受体γt(RORγt)、信号转导子和转录激活子3(STAT3)、白细胞介素-17A(IL-17A)和白细胞介素-17F(IL-17F)的mRNA及蛋白表达水平。结果与对照组比较,SFAE浓度在0.01 mg·mL^-1时对初始CD4^+T细胞的活力有抑制作用(P<0.01),选择该浓度作为后续实验浓度。与对照组比较,模型组能明显上调CD4^+IL-17A+T细胞的比例(P<0.001),上调RORγt、STAT3、IL-17A、IL-17F mRNA及蛋白的表达(P<0.01,P<0.001)。与模型组比较,SFAE干预后模型处理组的CD4^+IL-17A+T细胞比例明显下调(P<0.05),STAT3、RORγt、IL-17A、IL-17F mRNA及蛋白表达水平均明显下调(P<0.05,P<0.01)。结论SFAE能够抑制Th17细胞分化,降低Th17细胞比例,其作用机制可能是通过抑制转录因子RORγt及STAT3的活性,降低IL-17A、IL-17F的表达。