Pan Guoqing, Bao Jialing, Ma Zhengang, Song Yue, Han Bing, Ran Maoshuang, Li Chunfeng, Zhou Zeyang
State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, PR China.
College of Life Sciences, Chongqing Normal University, Chongqing 401331, PR China.
Dev Comp Immunol. 2018 Jun;83:104-113. doi: 10.1016/j.dci.2018.02.004. Epub 2018 Feb 8.
Microsporidia are a group of fungi-like intracellular and unicellular parasites, which infect nearly all animals. As "master parasites", over 1400 microsporidian species have been described to date. Microsporidia infections in economical invertebrates (e.g., silkworm, shrimp) cause huge financial losses, while other microsporidia infections in daphnia, nematode, locust, honeybee and mosquito play important roles in the regulation of their population size. Research investigating invertebrate host responses following microsporidia infections has yielded numerous interesting results, especially pertaining to the innate immune response to these pathogens. In this review, we comparatively summarize the invertebrate host responses to various microsporidia infections. We discuss numerous critical events in host responses including ubiquitin-mediated resistance, production of reactive oxygen species, melanization and innate immune pathways, and the increased basic metabolism and the accumulation of juvenile hormone in infected hosts. Recent studies progressing our understanding of microsporidia infection are also highlighted. Collectively, these advances shed more light on general rules of invertebrate host immune responses and pathogenesis mechanisms of microsporidia, and concurrently offer valuable clues for further research on the crosstalk between hosts and intracellular pathogens.
微孢子虫是一类真菌样的细胞内单细胞寄生虫，可感染几乎所有动物。作为“寄生大师”，迄今为止已描述了1400多种微孢子虫物种。经济无脊椎动物（如蚕、虾）中的微孢子虫感染会造成巨大的经济损失，而水蚤、线虫、蝗虫、蜜蜂和蚊子中的其他微孢子虫感染在调节其种群数量方面发挥着重要作用。对微孢子虫感染后无脊椎动物宿主反应的研究产生了许多有趣的结果，特别是关于对这些病原体的先天免疫反应。在本综述中，我们比较总结了无脊椎动物宿主对各种微孢子虫感染的反应。我们讨论了宿主反应中的许多关键事件，包括泛素介导的抗性、活性氧的产生、黑化和先天免疫途径，以及受感染宿主中基础代谢的增加和保幼激素的积累。还强调了最近增进我们对微孢子虫感染理解的研究。总的来说，这些进展更清楚地揭示了无脊椎动物宿主免疫反应的一般规律和微孢子虫的致病机制，同时为进一步研究宿主与细胞内病原体之间的相互作用提供了有价值的线索。
