Korša Ana, Lo Lai Ka, Gandhi Shrey, Bang Corinna, Kurtz Joachim
Institute for Evolution and Biodiversity, University of Münster, Münster, Germany.
Department of Genetic Epidemiology, Institute of Human Genetics, University of Münster, Münster, Germany.
Front Microbiol. 2022 Apr 13;13:793143. doi: 10.3389/fmicb.2022.793143. eCollection 2022.
It is now well-established that the microbiome is relevant for many of an organism's properties and that its composition reacts dynamically to various conditions. The microbiome interacts with host immunity and can play important roles in the defenses against pathogens. In invertebrates, immune priming, that is, improved survival upon secondary exposure to a previously encountered pathogen, can be dependent upon the presence of the gut microbiome. However, it is currently unknown whether the microbiome changes upon priming treatment. We here addressed this question in a well-established model for immune priming, the red flour beetle exposed to the entomopathogenic bacterium (). After priming treatments, the microbiota composition of beetle larvae was assessed by deep sequencing of the V1-V2 region of the bacterial 16S rRNA gene. We compared the effect of two established routes of priming treatments in this system: injection priming with heat-killed and oral priming ingestion of filtered sterilized bacterial spore culture supernatants. For oral priming, we used several strains of known to vary in their ability to induce priming. Our study revealed changes in microbiome composition following the oral priming treatment with two different strains of , only one of which () is known to lead to improved survival. In contrast, injection priming treatment with the same bacterial strain did not result in microbiome changes. Combined with the previous results indicating that oral priming with depends on the larval microbiome, this suggests that certain members of the microbiome could be involved in forming an oral priming response in the red flour beetle.
现在已经充分证实，微生物群与生物体的许多特性相关，并且其组成会对各种条件做出动态反应。微生物群与宿主免疫系统相互作用，并在抵御病原体方面发挥重要作用。在无脊椎动物中，免疫致敏，即再次接触先前遇到的病原体时存活率提高，可能取决于肠道微生物群的存在。然而，目前尚不清楚微生物群在致敏处理后是否会发生变化。我们在此通过一个成熟的免疫致敏模型——暴露于昆虫病原细菌（）的赤拟谷盗来解决这个问题。在进行致敏处理后，通过对细菌16S rRNA基因V1-V2区域进行深度测序，评估甲虫幼虫的微生物群组成。我们比较了该系统中两种既定致敏处理途径的效果：用热灭活的进行注射致敏和口服致敏（摄入过滤灭菌的细菌孢子培养上清液）。对于口服致敏，我们使用了几种已知诱导致敏能力不同的菌株。我们的研究表明，用两种不同菌株进行口服致敏处理后，微生物群组成发生了变化，其中只有一种菌株（）已知能提高存活率。相比之下，用相同细菌菌株进行注射致敏处理并未导致微生物群变化。结合先前的结果表明，用进行口服致敏取决于幼虫的微生物群，这表明微生物群的某些成员可能参与了赤拟谷盗口服致敏反应的形成。
