Microbiota-gamma delta IEL-Paneth cell axis in host antimicrobial response

项目摘要。 维持完整的肠屏障对于防止粘膜微生物活化至关重要。 免疫力gd上皮内淋巴细胞（IEL）在上皮区室中广泛迁移， 作为抵抗腔抗原和侵入性肠道微生物的第一道防线， 参与调节潘氏细胞分泌抗菌肽。虽然微生物来源 分子有助于gd IEL稳态，特定的肠道细菌尚未与 gd IEL数目和/或功能改变。此外，gd IEL介导的 信号传导对潘氏细胞功能的影响还有待探索。在为此生成的初步数据中， 应用中，我们确定了5个扩增子序列变体（ASV），它们与 在稳态条件下gd IEL的扩张。我们还表明，从WT分离的上皮细胞， 具有扩大的gd IEL隔室的小鼠也表现出参与以下的基因的显著上调： 潘氏细胞抗菌肽的产生和分泌。因此，本建议旨在确定 个别的天体对Gd IEL腔室膨胀的贡献，并确定 显示这种过度增殖表型的WT小鼠中gd IEL-Paneth细胞串扰的程度。 使用结合独特鼠标模型和尖端成像的集成方法 技术在体外和体内，这些研究将是第一个确定的贡献， 个别个体在gd IEL增殖和监视行为的扩增中的表现，以及 阐明gd IEL是否直接促进潘氏细胞功能。更好地了解 微生物群-gdIEL-Paneth细胞轴可以鉴定新的治疗靶点以帮助宿主防御， 有助于维持克罗恩病患者的缓解。

PROJECT SUMMARY. Maintenance of an intact intestinal barrier is critical to prevent microbial activation of mucosal immunity. gd intraepithelial lymphocytes (IEL) migrate extensively within the epithelial compartment to serve as a first line of defense against luminal antigens and invasive enteric microbes, and have been implicating in regulating Paneth cell secretion of antimicrobial peptides. Although microbial-derived molecules contribute to gd IEL homeostasis, specific commensal bacteria have yet to be associated with alterations in gd IEL number and/or function. Moreover, the extent to which gd IEL-mediated signaling influences Paneth cell function has yet to be explored. In preliminary data generated for this application, we identified 5 amplicon sequence variants (ASV) that are strongly associated with the expansion of gd IELs under homeostatic conditions. We also show that epithelial cells isolated from WT mice with an expanded gd IEL compartment also exhibit a significant upregulation of genes involved in Paneth cell antimicrobial peptide production and secretion. Therefore, this proposal seeks to identify the contribution of individual commensals to the expansion of the gd IEL compartment and determine the extent of gd IEL-Paneth cell crosstalk in WT mice exhibiting this hyperproliferative phenotype. Using an integrated approach that combines unique mouse models and cutting edge imaging technologies both in vitro and in vivo, these studies will be the first to identify the contribution of individual commensals in the amplification of gd IEL proliferation and surveillance behavior, and elucidate whether gd IELs directly promote Paneth cell function. Developing a better understanding of the microbiota-gd IEL-Paneth cell axis may identify novel therapeutic targets to aid in host defense and help maintain remission in Crohn’s disease patients.