Zhao Xiaoheng, Liu Lichun, Hegazy Abeer M, Wang Hong, Li Jie, Zheng Feifei, Zhou Yang, Wang Weimin, Li Jun, Liu Xiaoling, Lin Li
Department of Aquatic Animal Medicine, College of Fisheries, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, Hubei 430070, China.
Department of Aquatic Animal Medicine, College of Fisheries, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
Fish Shellfish Immunol. 2015 Apr;43(2):357-63. doi: 10.1016/j.fsi.2015.01.002. Epub 2015 Jan 9.
Mannose receptor (MR) is an important pattern-recognition receptor in macrophages and plays a critical role in immune responses. It is has been reported that mammalian macrophages are able to engulf a wide range of microorganisms mediated by Ca(2+)-dependent MR binding to terminal mannose residues which are frequently found on the pathogen surfaces. However, little is known about the MR-mediated phagocytosis in macrophages of fish. In this report, the distributions of MR in the macrophage and head kidney tissue from blunt snout bream were examined using MaMR specific antibody generated in our lab. Mannan and MaMR specific antibody inhibition experiments results collectively showed that MR was involved in the GFP-expressed E. coli engulfed in the macrophages, resulting in respiratory burst, nitric oxide production as well as inflammatory cytokines secretion, and the MaMR-mediated phagocytosis was Ca(2+)-dependent. These results will shed a new light on the immune functions of teleost MRs.
甘露糖受体（MR）是巨噬细胞中一种重要的模式识别受体，在免疫反应中起关键作用。据报道，哺乳动物巨噬细胞能够通过依赖钙离子的MR与病原体表面常见的末端甘露糖残基结合，吞噬多种微生物。然而，关于鱼类巨噬细胞中MR介导的吞噬作用知之甚少。在本报告中，我们使用实验室制备的MaMR特异性抗体，检测了团头鲂巨噬细胞和头肾组织中MR的分布。甘露聚糖和MaMR特异性抗体抑制实验结果共同表明，MR参与了巨噬细胞中吞噬表达绿色荧光蛋白的大肠杆菌的过程，导致呼吸爆发、一氧化氮产生以及炎性细胞因子分泌，并且MaMR介导的吞噬作用是依赖钙离子的。这些结果将为硬骨鱼MR的免疫功能提供新的见解。
