Response of kidney resident macrophages to proximal tubule injury

项目摘要 这个NIH F30应用程序描述了一个为期四年的指导研究和职业发展的PI计划， 马修·张这一建议的科学前提是集中在肾脏驻留巨噬细胞的作用 以及它们对急性肾损伤（阿基）的反应。阿基是一种主要并发症，影响高达20%的住院患者 60%的重症患者。尽管死亡率和发生频率很高，但靶向治疗 治疗阿基的方法尚未成功开发。先天免疫系统，特别是巨噬细胞， 在阿基的发病机制和愈合中起重要作用，并可能成为未来治疗的重要组成部分。 初步研究表明，涉及肾脏驻留巨噬细胞（KRM）的研究数量正在增加 它们在肾内稳态和损伤愈合中至关重要。KRM调节对阿基的反应，但 其作用机制尚不清楚。在这里，我们将阐明分子和细胞 KRM如何维持和恢复损伤后的肾功能。我们初步的单细胞 RNA测序数据表明，KRM群体由几个未描述的亚群组成， 不同的功能。空间转录组学表明，这些亚群居住在不同的微环境中， 并且至少一个似乎响应于损伤而迁移到近端小管。我们还发现， 在小鼠和人类中表达高水平的补体蛋白和模式识别分子C1 q。 我们的中心假设是KRM亚群对肾损伤有明确的转录反应， C1 q依赖性的PTEC损伤。我们将通过单细胞和空间 转录组学和各种体外和体内实验，包括使用C1 q缺陷的小鼠 KRM中的表达和近端小管特异性损伤模型。了解各种参与 KRM亚群和C1 q，KRM产生的最丰富的蛋白质之一，将有显着的 影响我们对阿基治疗靶向机制的理解。拟议的培训 PI计划由共同导师Anupam Agarwal（医学博士）和James乔治（博士）赞助。纳入 培训计划的经验，将帮助马修发展在三个主要领域：1）严格的免疫 急性肾损伤的研究，包括熟悉现有文献，批判性评价 2）严格的高级生物信息学培训， 下一代测序分析和3）职业和专业发展，包括赠款和 论文写作、科学交流以及将研究成果转化为临床应用。 该提案推动了严格的科学研究关键免疫学所需技能的发展， 高级生物信息学技能是PI未来作为肾脏科医生-科学家的职业生涯所必需的， 精准医疗和免疫介导的肾脏疾病。

PROJECT SUMMARY This NIH F30 application describes a four-year plan for mentored research and career development for the PI, Matthew Cheung. The scientific premise of this proposal is focused on the role of kidney resident macrophages and their responses to acute kidney injury (AKI). AKI is a major complication affecting up to 20% of hospitalized and 60% of critically ill patients. Despite the high mortality rate and frequency of occurrence, targeted therapies to treat AKI have not been successfully developed. The innate immune system, particularly macrophages, are important in the pathogenesis and healing in AKI and will likely be an important component of future therapies. Studies involving kidney resident macrophages (KRMs) are increasing in number as preliminary studies suggest that they are crucial in renal homeostasis and healing from injury. KRMs modulate the response to AKI, but the mechanism of their contribution remains unknown. Here, we will elucidate the molecular and cellular mechanisms that govern how KRMs maintain and restore renal function after injury. Our preliminary single-cell RNA sequencing data suggest that the KRM population consists of several undescribed subpopulations with distinct functions. Spatial transcriptomics shows that these subpopulations reside in distinct microenvironments and at least one appears to migrate to the proximal tubules in response to injury. We have also found that KRMs in both mice and humans express high levels of the complement protein and pattern recognition molecule C1q. Our central hypothesis is KRM subpopulations have a defined transcriptional response to renal injury and react to PTEC damage in a C1q-dependent manner. We will test this hypothesis through single-cell and spatial transcriptomics and a variety of in vitro and in vivo experiments, including the use of mice deficient in C1q expression in KRMs and a model of proximal tubule-specific injury. Understanding the involvement of the various KRM subpopulations and of C1q, one of the most abundant proteins produced by KRMs, will have a significant impact on our understanding of mechanisms that can be targeted for the treatment of AKI. The proposed training plan for the PI is sponsored by co-mentors Anupam Agarwal, MD, and James George, PhD. Included in the training plan are experiences that will help Matthew develop in three major areas: 1) rigorous immunological research in acute kidney injury, which includes developing familiarity with the existing literature, critical evaluation of data, and training in the responsible conduct of research; 2) rigorous training in advanced bioinformatics and next-generation sequencing analysis and 3) career and professional development, including grant and manuscript writing, scientific communications, and the translation of research findings to clinical applications. This proposal drives the development of skills required for rigorous scientific research critical immunology and advanced bioinformatics skills necessary for the PI’s future career as a nephrology physician-scientist focused on precision medicine and immune-mediated kidney diseases.