UPR9022, University of Strasbourg, Institut de Biologie Moléculaire et Cellulaire (IBMC), Modèles Insectes D'Immunité Innée (M3I) Unité Propre Recherche (UPR) 9022 du Centre National de la Recherche Scientifique (CNRS), Strasbourg, France.
Front Immunol. 2022 Apr 13;13:858360. doi: 10.3389/fimmu.2022.858360. eCollection 2022.
Microsporidia are obligate intracellular parasites able to infest specifically a large range of species, including insects. The knowledge about the biology of microsporidial infections remains confined to mostly descriptive studies, including molecular approaches such as transcriptomics or proteomics. Thus, functional data to understand insect host defenses are currently lacking. Here, we have undertaken a genetic analysis of known host defenses of the using an infection model whereby spores are directly injected in this insect. We find that phagocytosis does confer some protection in this infection model. In contrast, the systemic immune response, extracellular reactive oxygen species, thioester proteins, xenophagy, and intracellular antiviral response pathways do not appear to be involved in the resistance against this parasite. Unexpectedly, several genes such as seem to promote this infection. The prophenol oxidases that mediate melanization have different functions; presents a phenotype similar to that of whereas that of suggests a function in the resilience to infection. Similarly, and , which encode two cytokines secreted by hemocytes display a resilience phenotype with a strong susceptibility to .
微孢子虫是专性细胞内寄生虫，能够专门感染包括昆虫在内的多种物种。对微孢子虫感染生物学的了解仍然局限于大多数描述性研究，包括转录组学或蛋白质组学等分子方法。因此，目前缺乏用于了解昆虫宿主防御功能的功能数据。在这里，我们使用一种感染模型对 的已知宿主防御进行了遗传分析，在该模型中，孢子直接注射到这种昆虫中。我们发现吞噬作用确实能在这种感染模型中提供一定的保护。相比之下，全身性免疫反应、细胞外活性氧物质、硫酯蛋白、异源吞噬和细胞内抗病毒反应途径似乎不参与抵抗这种寄生虫。出乎意料的是，有几个基因，如 ，似乎促进了这种感染。介导黑化的酚氧化酶具有不同的功能； 呈现出与 相似的表型，而 则表明其在抵御感染方面的功能。同样，编码两种由血细胞分泌的细胞因子的 和 表现出对 的抗性表型，对 的敏感性很强。
