Modulation of immune cell phenotype by hormone-producing epithelia in autoimmune endocrinopathies

在自身免疫性内分泌疾病中，自身反应性T细胞不适当地靶向分泌细胞， 组织损伤和荷尔蒙分泌的消失。最常见的自身免疫性疾病之一， 桥本氏甲状腺炎，提供了一个理想的模型，以破译激素的生产是如何失去了自身免疫性疾病 内分泌疾病令人惊讶的是，只有20-40%的桥本甲状腺炎患者表现出激素的损失 生产（甲状腺功能减退）。其余的患者保留激素的生产，尽管免疫浸润的细胞。 甲状腺（甲状腺功能正常）。了解激素的产生是如何保存的需要解剖的相互作用 在浸润性T细胞和产生细胞毒性的上皮细胞之间，如甲状腺细胞。为了应付这一挑战， 我对桥本甲状腺炎患者的甲状腺进行了单细胞RNA测序， Graves病（甲状腺自身免疫的一种自身抗体驱动形式）和那些没有自身免疫性甲状腺疾病的人 疾病我们已经确定了一个转录独特的甲状腺细胞群体，在生长发育过程中显著扩增。 桥本甲状腺炎和异位表达II类MHC。此外，我们的初步数据显示， 甲状腺浸润性CD 4 + T细胞群似乎可以区分Graves病和桥本氏病 甲状腺炎已知上皮细胞在发炎组织中表达MHCII，但是不知道这些细胞是否表达MHCII。 细胞在体内将抗原呈递给CD 4 + T细胞。我们假设MHCII+甲状腺细胞呈递抗原， 调节CD 4 + T细胞的表型，导致炎症环境的全面变化。我们进一步 假设MHCII+甲状腺细胞的转录表型在甲状腺功能正常和甲状腺功能减退中不同 桥本氏甲状腺炎。为了验证这些假设，我将比较转录和功能表型， 甲状腺功能正常和甲状腺功能减退的桥本甲状腺炎和Graves病中的MHCII+甲状腺细胞（目的1）。然后我将 确定甲状腺浸润性自身反应性T细胞在这些条件下的差异（目的2）。这个项目可能 更广泛地定义了在自身免疫性疾病中组织功能是如何保留的。 该提案提出了一个五年计划，米歇尔Rengarajan博士在免疫学培训，以破译如何 上皮免疫相互作用是内分泌自身免疫的基础。Rengarajan博士将成为医学讲师 在哈佛医学院（HMS）和马萨诸塞州总医院（MGH）。她将执行提议的 在Andrew Luster博士和Alexandra-Chloe Villani博士的指导下工作。Rengarajan博士概述了一个 职业发展计划侧重于单细胞基因组学，上皮免疫相互作用，抗原特异性T 细胞，并在科学沟通和领导力的额外培训。Rengarajan博士的长期目标是 发展一个独立的研究项目，研究自身免疫性内分泌疾病的机制基础。的 本提案中概述的实验和培训计划， 环境，以及HMS和MGH可用的资源将成功地将Rengarajan博士定位为她的第一个 R 01和一个独立的职业生涯作为一个物理学家，科学家。

In autoimmune endocrine disease, self-reactive T cells inappropriately target hormone-producing cells, leading to tissue damage and obliteration of hormone production. One of the most common autoimmune diseases, Hashimoto’s thyroiditis, offers an ideal model to decipher how hormone production is lost in autoimmune endocrine disease. Surprisingly, only 20-40% of patients with Hashimoto’s thyroiditis exhibit loss of hormone production (hypothyroid). The remainder of patients retain hormone production despite immune infiltration of the thyroid (euthyroid). Understanding how hormone production is preserved requires dissection of interactions between infiltrating T cells and hormone-producing epithelial cells, such as thyrocytes. To address this challenge, I have performed single-cell RNA sequencing in human thyroid from patients with Hashimoto’s thyroiditis, Graves’ disease (an autoantibody-driven form of thyroid autoimmunity) and those without autoimmune thyroid disease. We have identified a transcriptionally unique population of thyrocytes that is significantly expanded in Hashimoto’s thyroiditis and ectopically expresses class II MHC. In addition, our preliminary data indicate several thyroid-infiltrating CD4+ T cell populations that appear to distinguish Graves’ disease from Hashimoto’s thyroiditis. Epithelial cells are known to express MHCII in inflamed tissue, however it is not known whether these cells present antigen to CD4+ T cells in vivo. We hypothesize that MHCII+ thyrocytes present antigen to and modulate the phenotype of CD4+ T cells, leading to global changes in the inflammatory environment. We further hypothesize that the transcriptional phenotype of MHCII+ thyrocytes differs in euthyroid and hypothyroid Hashimoto’s thyroiditis. To test these hypotheses, I will compare the transcriptional and functional phenotype of MHCII+ thyrocytes in euthyroid and hypothyroid Hashimoto’s thyroiditis and Graves’ disease (Aim 1). I will then determine how thyroid-infiltrating self-reactive T cells differ among these conditions (Aim 2). This project may define how tissue function can be preserved in autoimmune disease more broadly. This proposal presents a five-year plan for Dr. Michelle Rengarajan to train in immunology to decipher how epithelial-immune interactions underly endocrine autoimmunity. Dr. Rengarajan will be an Instructor in Medicine at Harvard Medical School (HMS) and Massachusetts General Hospital (MGH). She will perform the proposed work under mentorship from Drs. Andrew Luster and Alexandra-Chloe Villani. Dr. Rengarajan has outlined a career development plan focused on single-cell genomics, epithelial-immune interactions, antigen-specific T cells, with additional training in scientific communication and leadership. Dr. Rengarajan’s long-term goal is to develop an independent research program studying the mechanistic basis of autoimmune endocrinopathies. The experiments and training plan outlined in this proposal, with the collaborative opportunities, intellectual environment, and resources available at HMS and MGH will successfully position Dr. Rengarajan for her first R01 and an independent career as a physician-scientist.