病原微生物荚膜多糖的生物学功能

荚膜多糖（capsular polysaccharide，CPS）是一种广泛存在于细菌、支原体、部分真菌等菌体表面的碳水化合物。同时，荚膜多糖有助于菌体抵抗干燥和低温等不利环境，并通过在菌体表面形成物理屏障阻碍宿主补体的杀伤与吞噬作用。在长期多种应激-压力环境下，病原菌已进化出多种免疫逃避机制并促进宿主感染；在非病原微生物中，荚膜多糖可正向调节宿主免疫作用，并拮抗机体免疫因子，保护宿主免受病原菌引起的炎症性疾病。本文将结合本团队的相关研究工作，对荚膜多糖的结构、合成调控机制、生物学功能、免疫逃避机制和致病机制，特别是荚膜多糖正向调节宿主免疫系统及其应用潜力等方面作一综述，为病原菌致病机制的研究和疫病的有效防控提供参考依据。

Research Progress on the Function and Immunity of Capsular Polysaccharide

Capsular polysaccharide(CPS)is a carbohydrate that is widely present on the surface of bacteria,mycoplasma,and some fungi.At the same time,CPS can help the bacteria resist the adverse environment such as dry and low temperature,and block the killing of host complement and phagocytosis by forming a physical barrier on the surface of bacteria.Under long-term multiple stress environments,pathogens have evolved a variety of immune escape mechanisms and promote host infection;among non-pathogenic microorganisms,CPS can positively regulate host immune function,and antagonize immune factors,to protect the host from inflammatory diseases caused by pathogens.This article will combine the relevant research works of our team to review the structure,synthesis regulatory mechanisms,biological function,immune evasion mechanism and pathogenic mechanism of CPS,especially the positive regulation of the host immune system by CPS and its application potential,to provide references for the research on pathogenic mechanisms of pathogenic bacteria and effective prevention and control of epidemic diseases.