Investigating the skin-immune system in dirty mice

项目摘要 几十年来，小鼠模型一直是免疫学研究的有力工具，提供了令人难以置信的见解 我们对免疫系统的理解。然而，在许多情况下，小鼠的观察结果并不能转化为 人类环境中不断的微生物暴露在人类中产生了一种广泛而多样的 记忆T细胞群，包括组织驻留记忆T细胞（TRM）。皮肤TRM在人类中起着关键作用 皮肤健康和疾病。保持在无特定病原体（SPF）条件下的标准实验室小鼠缺乏免疫原性。 真正的记忆T细胞群，包括皮肤TRM，限制了它们在皮肤疾病研究中的效用， TRM可能是因果关系，也可能是促成关系。此外，我们现在知道微生物组极大地影响免疫力， 和炎症，但SPF小鼠的微生物组非常有限。最近的突破性工作表明， 实验室小鼠与宠物店小鼠共同饲养获得了一个强大的和多样化的记忆T细胞群， 人类的记忆T细胞群，包括皮肤TRM。此外，数据表明，调节性T细胞， 记忆B细胞和先天免疫细胞在共同饲养的“脏”小鼠中也发生了改变。不同微生物 暴露促使免疫细胞群发生了巨大的变化。脏老鼠可能有潜在的深远影响 对整个皮肤免疫学领域的影响，作为一个更像人类的小鼠模型， 翻译研究作为第一步，脏老鼠的皮肤免疫系统必须得到很好的表征， 这些小鼠在免疫介导的皮肤病模型中进行测试。在目标1中，我们将彻底描述 不同品系、性别、皮肤部位脏对照小鼠与清洁对照小鼠的皮肤免疫系统 不同的微生物暴露。因此，结果将广泛适用于皮肤免疫学社区。 我们将使用新的和传统的技术，包括单细胞RNA测序，批量RNA测序， 高通量TCR测序、高参数流式细胞术和组织免疫荧光染色， 显微镜在目标2中，我们将在两种免疫介导皮肤的创新模型中测试脏小鼠与干净小鼠 疾病、移植物抗宿主病和药物超敏反应。充足的人类数据支持 记忆T细胞，特别是皮肤TRM在这两种疾病中，但缺乏含有这些细胞的小鼠模型， 日期排除了机械审讯。我们假设脏老鼠会更好地模仿这两个人类 皮肤疾病，并将为研究皮肤TRM和疾病中的微生物组提供新的途径 发病机制向前发展。总之，这项创新工作是可行的，可推广的，并具有潜在的变革性 皮肤免疫学领域。

Project Summary Mouse models have served as a powerful tool in immunology research for decades, providing incredible insight into our understanding of the immune system. However, in many cases, observations in mice do not translate to humans. Constant microbial exposure from the environment generates in humans an expansive and diverse memory T cell population, including tissue resident memory T cells (TRM). Skin TRM play critical roles in human skin health and disease. Standard laboratory mice maintained in specific pathogen free (SPF) conditions lack a true memory T cell population, including skin TRM, limiting their utility in the study of skin diseases where skin TRM may be causal or contributory. Moreover, we now know that the microbiome greatly influences immunity and inflammation, yet SPF mice have a very restricted microbiome. Recent ground-breaking work demonstrated that laboratory mice co-housed with pet shop mice acquire a robust and diverse memory T cell population akin to memory T cell populations in humans, including skin TRM. Moreover, data suggested that regulatory T cells, memory B cells and innate immune cells were also altered in the co-housed “dirty” mice. Diverse microbial exposure drove this dramatic shift in immune cell populations. Dirty mice could have a potentially profound impact on the entire field of skin immunology, by serving as a more human-like mouse model for translational research. As a first step though, the skin immune system of dirty mice must be well-characterized, and these mice tested in models of immune-mediated skin disease. In Aim 1, we will thoroughly characterize the skin immune system in dirty versus clean control mice of different strains, sex, skin site, and as a consequence of varying microbial exposure. Results will therefore be broadly applicable to the skin immunology community. We will use both novel and traditional techniques including single cell RNA sequencing, bulk RNA sequencing, high throughput TCR sequencing, high parameter flow cytometry and tissue immunofluorescence staining with microscopy. In Aim 2, we will test dirty versus clean mice in innovative models of two immune-mediated skin diseases, graft-versus-host-disease and drug hypersensitivity reaction. Ample human data support a role for memory T cells, particularly skin TRM in both diseases but lack of a mouse model containing these cells has to- date precluded mechanistic interrogation. We hypothesize that dirty mice will superiorly model these two human skin diseases and will provide a novel avenue for investigating skin TRM and microbiome in disease pathogenesis going forward. In sum, this innovative work is feasible, generalizable, and potentially transformative to the field of skin immunology.