Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health , Baltimore , MD , USA.
Virulence. 2019 Dec;10(1):822-831. doi: 10.1080/21505594.2018.1431087. Epub 2018 Aug 1.
The capsule of is its dominant virulence factor and plays a key role in the biology of this fungus. In this essay, we focus on the capsule as a cellular structure and note the limitations inherent in the current methodologies available for its study. Given that no single method can provide the structure of the capsule, our notions of what is the cryptococcal capsule must be arrived at by synthesizing information gathered from very different methodological approaches including microscopy, polysaccharide chemistry and physical chemistry of macromolecules. The emerging picture is one of a carefully regulated dynamic structure that is constantly rearranged as a response to environmental stimulation and cellular replication. In the environment, the capsule protects the fungus against desiccation and phagocytic predators. In animal hosts the capsule functions in both offensive and defensive modes, such that it interferes with immune responses while providing the fungal cell with a defensive shield that is both antiphagocytic and capable of absorbing microbicidal oxidative bursts from phagocytic cells. Finally, we delineate a set of unsolved problems in the cryptococcal capsule field that could provide fertile ground for future investigations.
荚膜是 的主要毒力因子，在该真菌的生物学中起着关键作用。在本文中，我们将荚膜作为一种细胞结构进行研究，并指出当前研究荚膜的方法存在的固有局限性。鉴于没有一种方法可以提供荚膜的结构，我们对隐球菌荚膜的认识必须通过综合来自非常不同方法学方法的信息来得出，包括显微镜、多糖化学和大分子物理化学。新兴的观点是，荚膜是一种精心调控的动态结构，会根据环境刺激和细胞复制不断重新排列。在环境中，荚膜保护真菌免受干燥和吞噬性捕食者的侵害。在动物宿主中，荚膜具有进攻和防御两种功能，它干扰免疫反应的同时，为真菌细胞提供一个防御盾牌，既能抗吞噬又能吸收吞噬细胞产生的杀菌性氧化爆发。最后，我们描述了隐球菌荚膜领域的一组未解决的问题，这些问题可能为未来的研究提供肥沃的土壤。
