Modulation of the biliary immune niche by the microbiome

项目总结/摘要 胆道疾病和炎症，包括小儿胆道闭锁和原发性硬化性胆管炎， 肝衰竭的主要原因慢性胆道炎症，这可能与存在 胆结石是发展胆管癌的危险因素，胆管癌是一种罕见但致命的恶性肿瘤。急性 胆囊炎症或胆囊炎占所有胆道疾病住院的20%， 通常需要手术干预，如果不治疗，死亡率很高。一起，胆道疾病， 包括常见的胆结石，是人类健康的巨大负担。胆道炎症起着 在各种常见和罕见胆道疾病的进展中具有明确的作用，但是我们对 胆道内的炎症和免疫过程非常有限。 处于稳态的肝外胆管树中的常驻免疫细胞群从未如此 特征，以及宿主或环境因素是否会影响胆道生态位的发育， 从未被探索过。目前尚不清楚驻留的胆汁免疫细胞是否会影响发育和进展 胆道疾病在我的博士后培训期间，我开发了一种可重复的组织消化方法， 高活力的免疫、上皮和基质细胞群。单细胞RNA测序显示， 在小鼠胆囊/肝外胆管中以稳态存在多种常驻免疫细胞， 包括先天性淋巴细胞、适应性淋巴细胞、嗜中性粒细胞、巨噬细胞和树突细胞。在 胆管细胞研究过程-罕见的化学感受上皮细胞，具有已知的免疫调节作用 特性-我发现胆管免疫生态位在没有簇细胞的情况下改变，并且对 宿主的微生物组状态。我的数据表明，微生物组和胆管上皮细胞（包括簇状细胞） 细胞）调节胆道免疫小生境的建立。在这个提案中，我将测试微生物组的作用， 和微生物代谢产物在设置胆汁免疫“基调”，并将确定在调节的作用， 胆汁免疫细胞组成。我将测试胆系免疫生态位的改变是否在体内平衡，特别是 中性粒细胞的存在或不存在可以影响胆固醇结石疾病的进展。到 为了实现这些目标，我与肝脏/胆道生物学和微生物组专家建立了合作关系 操作，并建立了职业发展计划，将有助于增加计算 独立这些研究将揭示宿主因素和胆道炎症之间的新联系， 治疗靶向胆道上皮细胞和微生物组影响胆道健康的潜力， 疾病

PROJECT SUMMARY/ABSTRACT Biliary tract disease and inflammation, including pediatric biliary atresia and primary sclerosing cholangitis, are leading causes of liver failure. Chronic biliary inflammation, which can be associated with the presence of gallstones, is a risk factor for development of cholangiocarcinoma, a rare but deadly malignancy. Acute inflammation of the gallbladder, or cholecystitis, accounts for 20% of all biliary tract disease hospitalizations, usually requires surgical intervention and has significant mortality if left untreated. Together, biliary tract disease, including common gallstones, represents an enormous human health burden. Biliary tract inflammation plays clear roles in progression of various common and rare biliary diseases, however our understanding of inflammation and immune processes within the biliary tract are exceedingly limited. The resident immune cell populations in the extrahepatic biliary tree at homeostasis have never been characterized, and whether host or environmental factors can influence the development of the biliary niche has never been explored. It is unknown if resident biliary immune cells could impact development and progression of biliary disease. During my postdoctoral training, I developed a reproducible tissue digest method that yields highly viable immune, epithelial, and stromal cell populations. Single cell RNA sequencing revealed that there is a diversity of resident immune cells present at homeostasis in the mouse gallbladder/extrahepatic bile ducts, including innate lymphoid cells, adaptive lymphocytes, neutrophils, macrophages, and dendritic cells. In the course of studying biliary tuft cells—rare, chemosensory epithelial cells with known immunomodulating properties—I found that the biliary immune niche is altered in the absence of tuft cells, and is also sensitive to the microbiome-status of the host. My data suggest that the microbiome and biliary epithelial cells (including tuft cells) regulate the establishment of the biliary immune niche. In this proposal, I will test the role of the microbiome and microbial metabolites in setting biliary immune “tone,” and will define a role for tuft cells in regulating the biliary immune cell make-up. I will test whether alterations in the biliary immune niche at homeostasis, specifically the presence or absence of neutrophils, can impact the progression of cholesterol gallstone disease. To accomplish these aims, I have formed collaborations with experts in liver/biliary biology and microbiome manipulations, and have established a career development plan that will facilitate increasing computational independence. These studies will reveal new links between host factors and biliary inflammation, with the potential for therapeutic targeting of biliary epithelial cells and the microbiome to impact biliary health and disease.