Laboratory of Invertebrate Immunological Defense and Reproductive Biology, School of Life Sciences, East China Normal University, Shanghai, China.
Laboratory of Invertebrate Immunological Defense and Reproductive Biology, School of Life Sciences, East China Normal University, Shanghai, China.
Dev Comp Immunol. 2022 Nov;136:104514. doi: 10.1016/j.dci.2022.104514. Epub 2022 Aug 14.
The inducible reductase of interferon gamma (IFN- γ), IFN-γ-induced lysosomal thiol reductase (GILT) is important in antiviral immunity, but its mechanism in invertebrate antimicrobial immunity is unclear. We determined that GILT protein was involved in the antibacterial immunity of Chinese mitten crab (Eriocheir sinensis). GILT protein was highly expressed in crab hemocytes and was significantly upregulated 6 h after bacterial stimulation. Recombinant E. sinensis GILT (rEsGILT) contained a CXXS active site that catalyzed disulfide bond reduction. Vibrio parahaemolyticus and Staphylococcus aureus were bound through interaction with peptidoglycan and lipopolysaccharide, respectively, and bacterial agglutination and clearance in the crabs was markedly promoted. Nevertheless, EsGILT exhibited no direct antibacterial or bactericidal activity. EsGILT also promoted crab hemocyte phagocytosis and played an anti-bacterial role, and inhibited hemocyte apoptosis. In summary, EsGILT promoted bacterial agglutination, clearance, and phagocytosis by recognizing and agglutinating pathogenic microorganisms and reduced the apoptosis level, indirectly participating in antibacterial reactions.
干扰素 γ（IFN-γ）诱导还原酶，即 IFN-γ诱导溶酶体硫醇还原酶（GILT），在抗病毒免疫中具有重要作用，但在无脊椎动物抗菌免疫中的机制尚不清楚。我们确定 GILT 蛋白参与了中华绒螯蟹（Eriocheir sinensis）的抗菌免疫。GILT 蛋白在蟹血细胞中高度表达，在细菌刺激后 6 小时显著上调。重组中华绒螯蟹 GILT（rEsGILT）含有一个 CXXS 活性位点，可催化二硫键还原。副溶血弧菌和金黄色葡萄球菌分别通过与肽聚糖和脂多糖相互作用而结合，并且螃蟹中的细菌聚集和清除明显得到促进。然而，EsGILT 没有直接的抗菌或杀菌活性。EsGILT 还通过识别和聚集病原菌促进蟹血细胞吞噬作用，并发挥抗细菌作用，同时抑制血细胞凋亡。总之，EsGILT 通过识别和聚集病原菌来促进细菌的聚集、清除和吞噬作用，并降低凋亡水平，从而间接参与抗菌反应。
