【摘要】 目的:探讨胶原样结构巨噬细胞受体(MARCO)在细菌脂蛋白(BLP)耐受巨噬细胞吞噬能力增强过程中的作用。方法:分离、分化和培养骨髓来源的巨噬细胞(BMDMs),并制备BLP耐受细胞;利用流式细胞术和荧光显微镜检测并比较BLP耐受与非耐受细胞吞噬细菌的能力,同时用流式细胞术和qPCR检测BLP耐受对MARCO蛋白及mRNA表达的影响;进一步利用小干扰RNA下调MARCO表达,通过流式细胞术及荧光技术探讨MARCO对BLP耐受巨噬细胞吞噬能力的影响。结果:BLP耐受巨噬细胞吞噬细菌的量较非耐受巨噬细胞明显增加(P<0.05);同时BLP耐受巨噬细胞膜表面MARCO蛋白表达水平较非耐受细胞明显升高,并且在细菌刺激后进一步增加,MARCO的mRNA水平变化与蛋白水平变化一致;下调MARCO表达后,BLP耐受巨噬细胞对细菌的吞噬能力明显下降,提示BLP耐受巨噬细胞吞噬能力增强与巨噬细胞膜表面MARCO蛋白的表达上调有关。结论:BLP耐受通过上调巨噬细胞膜表面MARCO蛋白的表达,增强其对细菌的吞噬能力。更多还原

【Abstract】 AIM: To investigate the role of macrophage receptor with collagenous structure(MARCO), class A scavenger receptor, in enhancing the phagocytosis of bacterial lipoprotein(BLP) tolerized macrophages. METHODS: Bone marrow derived macrophages(BMDMs) was differentiated and cultured. BLP-tolerized macrophages were induced by treating the BMDMs with BLP for 24 h while the naive BMDMs were unstimulated. The phagocytic capacities of BLP-tolerized BMDMs and the naive BMDMs were detected by flow cytometry and fluorescence microscopy. Meanwhile, the effect of BLP tolerance on MARCO protein and mRNA expression was assessed by flow cytometry and qPCR. Furthermore, the small interference RNA was applied to down-regulate the expression of MARCO, and the effect of MARCO on the phagocytosis was measured by flow cytometry and fluorescent technique. RESULTS: Compared with the naive BMDMs, a prominently larger quantity of bacteria was engulfed by BLP-tolerized BMDMs(P<0.05). In addition, the protein expression of MARCO significantly increased in BLP-tolerized BMDMs, and then the MARCO protein further increased after stimulated with bacteria. The mRNA level of MARCO was consistent with the protein. Moreover, after down-regulation of MARCO, the phagocytic capacity of BLP-tolerized BMDMs was noticed to decline conspicuously, indicating that the enhanced phagocytosis of BLP-tolerized BMDMs displayed a substantial correlation with the up-regulation of the MARCO expression on BLP-tolerized macrophages. CONCLUSION: BLP tolerance enhances the phagocytosis of BMDMs through the up-regulation of MARCO.更多还原