College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China; Postdoctoral Research Base, Henan Institute of Science and Technology, Xinxiang, China; Postdoctoral Research Station, Henan Agriculture University, Zhengzhou, China.
Amsterdam UMC, University of Amsterdam, Center for Experimental and Molecular Medicine, Amsterdam Infection & Immunity, Meibergdreef 9, 1105AZ Amsterdam, Netherlands.
J Microbiol Immunol Infect. 2019 Aug;52(4):516-525. doi: 10.1016/j.jmii.2019.03.003. Epub 2019 Mar 27.
Streptococcus suis (S. suis) type 2 (SS2) is an important zoonotic pathogen that causes swine streptococcosis, a widespread infectious disease that occurs in pig production areas worldwide and causes serious economic losses in the pork industry. Hosts recognize pathogen-associated molecular patterns (PAMPs) through pattern recognition receptors (PRRs) to activate both innate and acquired immune responses. However, S. suis has evolved multiple mechanisms to escape host defenses. Pathogenic proteins, such as enolase, double-component regulatory systems, factor H-combining proteins and other pathogenic and virulence factors, contribute to immune escape by evading host phagocytosis, reactive oxygen species (ROS), complement-mediated immune destruction, etc. SS2 can prevent neutrophil extracellular trap (NET) formation to avoid being trapped by porcine neutrophils and disintegrate host immunoglobulins via IgA1 hydrolases and IgM proteases. Currently, the pathogenesis of arthritis and meningitis caused by SS2 infection remains unclear, and further studies are necessary to elucidate it. Understanding immune evasion mechanisms after SS2 infection is important for developing high-efficiency vaccines and targeted drugs.
猪链球菌 2 型（SS2）是一种重要的人畜共患病病原体，可引起猪链球菌病，这是一种广泛存在于世界各地养猪地区的传染性疾病，给猪肉产业造成严重的经济损失。宿主通过模式识别受体（PRRs）识别病原体相关分子模式（PAMPs），从而激活先天和获得性免疫反应。然而，猪链球菌已经进化出多种机制来逃避宿主防御。致病蛋白，如烯醇酶、双组分调控系统、因子 H 结合蛋白和其他致病和毒力因子，通过逃避宿主吞噬、活性氧（ROS）、补体介导的免疫破坏等，有助于免疫逃逸。SS2 可以阻止中性粒细胞胞外陷阱（NET）的形成，从而避免被猪中性粒细胞捕获，并通过 IgA1 水解酶和 IgM 蛋白酶分解宿主免疫球蛋白。目前，SS2 感染引起关节炎和脑膜炎的发病机制尚不清楚，需要进一步研究阐明。了解 SS2 感染后的免疫逃逸机制对于开发高效疫苗和靶向药物非常重要。
