Nguyen Thu N Y, Matangkasombut Oranart, Ritprajak Patcharee
Graduate program in Oral Biology, Faculty of Dentistry, Chulalongkorn University.
Research Unit on Oral Microbiology and Immunology and Department of Microbiology, Faculty of Dentistry, Chulalongkorn University.
J Oral Sci. 2018 Dec 27;60(4):557-566. doi: 10.2334/josnusd.17-0426. Epub 2018 Nov 15.
Mannan (mannosylated glycoproteins) in the outermost layer of the Candida cell wall may be the first molecules that interact with host dendritic cells (DCs) and activate immune responses that determine disease outcomes. However, little is known about how different mannan structures of common oral Candida species affect DC activation. The effects of heat-inactivated (HI) yeast cells and soluble mannan of Candida albicans, Candida parapsilosis, and Candida dubliniensis on bone marrow-derived DC (BMDC) responses were compared. HI Candida and the mannan exhibited different effects on BMDC activation and functions, which could be due to other carbohydrate compositions in the yeast cell wall. Among Candida mannan, the C. albicans mannan was the weakest stimulus and induced only interferon (IFN)-γ production. This suggests the possibility that C. albicans mannan may skew T helper (Th) responses from protective Th17 toward Th1. In contrast, C. parapsilosis mannan caused strong BMDC activation and high production of several proinflammatory cytokines which possibly promote hyperinflammation. Meanwhile, C. dubliniensis mannan induced moderate BMDC responses, which may correlate with its lower pathogenicity. Therefore, mannan of each Candida species play distinct roles in DC responses and may be involved in the immunopathogenesis and disease severity of oral candidiasis as well as other Candida infection.
念珠菌细胞壁最外层的甘露聚糖（甘露糖基化糖蛋白）可能是最先与宿主树突状细胞（DC）相互作用并激活免疫反应的分子，这些免疫反应决定了疾病的转归。然而，对于常见口腔念珠菌不同的甘露聚糖结构如何影响DC激活，人们了解甚少。比较了白色念珠菌、近平滑念珠菌和都柏林念珠菌的热灭活（HI）酵母细胞及可溶性甘露聚糖对骨髓来源DC（BMDC）反应的影响。HI念珠菌和甘露聚糖对BMDC的激活及功能表现出不同影响，这可能归因于酵母细胞壁中的其他碳水化合物成分。在念珠菌甘露聚糖中，白色念珠菌甘露聚糖是最弱的刺激物，仅诱导干扰素（IFN）-γ产生。这提示白色念珠菌甘露聚糖可能使辅助性T（Th）反应从具有保护性的Th17向Th1偏移。相比之下，近平滑念珠菌甘露聚糖引起强烈的BMDC激活及多种促炎细胞因子的高表达，这可能促进过度炎症反应。同时，都柏林念珠菌甘露聚糖诱导适度的BMDC反应，这可能与其较低的致病性相关。因此，每种念珠菌的甘露聚糖在DC反应中发挥不同作用，可能参与口腔念珠菌病以及其他念珠菌感染的免疫发病机制和疾病严重程度。
