In situ analysis of functional endocrine, vascular, and immune cell interactions during early postnatal development of the human pancreas

如果1型糖尿病的原因尚不清楚，主要是因为人类胰岛及其 与免疫系统的相互作用尚未研究。糖尿病研究界现在正在 在啮齿动物糖尿病模型中获得的结果与人类情况缺乏相关性。在 在回应中，有一个新的协调一致的努力，以获得和研究有关材料，即人类 胰腺，在健康和疾病。这项研究计划的长期目标是了解 以及在向糖尿病状态发展过程中在人胰岛中发生的生理变化。的 本申请的目的是确定内分泌、血管和免疫区室如何成熟 并且在胰岛的出生后发育期间在功能上相互作用。我们将专注于青少年的成熟 这是因为它是一个阶段，在此期间，早期出现的自身免疫性是强烈相关的， 易患1型糖尿病最重要的假设是β细胞介导的 自身免疫性与胰岛细胞分子表型的发育改变以及 胰岛结构的变化。我们认为成熟过程使胰岛易受炎症影响 并促进自身免疫的发展。拟议研究的基本原理是， 是什么使这个小岛变得脆弱不仅有助于解释它的垮台，而且还为干预提供了线索。 战略布局因此，该项目与NIH的使命相关，并对研究目标做出响应 来自NIDDK的资助机会公告，题为“人类高分辨率探索”， 胰岛组织环境”。在初步数据的指导下，我们将通过追求三个具体的假设来测试我们的假设。 目的：（1）确定胰岛内分泌细胞功能成熟的机制，（2）确定如何 建立血管功能的内分泌控制，和（3）确定表型的变化， 胰岛驻留巨噬细胞的行为。在第一个目标下，我们将研究大规模的结构和功能 β细胞和α细胞达到其全部分泌潜力所需的变化。在这三个目标中，我们将记录 细胞反应与功能成像和测量激素释放的活胰腺切片从供体 0至10岁。这些研究将通过对从细胞中分选的细胞的scRNA-seq分析来补充。 孤立的小岛在第二个目标下，我们将确定内分泌细胞如何建立对细胞的控制。 血管周细胞，胰岛中血流的主要调节器。在第三个目标下，我们将研究 胰岛驻留巨噬细胞的表型和功能在胰岛成熟过程中发生变化。的 拟议的研究是重要的，因为预期的结果可以揭示发展过程， 削弱胰岛的天然防御能力并引发局部免疫细胞的异常反应。知道这些 过程是至关重要的，以提出干预目标，旨在预防1型糖尿病的发展。

If the causes of type 1 diabetes are not known it is mainly because the human pancreatic islet and its interactions with the immune system have not been studied. The diabetes research community is now coming to terms with the lack of relevance to the human situation of results obtained in rodent models of diabetes. In response, there is a new concerted effort at obtaining and studying the relevant material, namely the human pancreas, in health and disease. The long-term goal of this research program is to understand the anatomical and physiological changes that occur in the human islet during the progression towards the diabetic state. The objective of this application is to determine how the endocrine, vascular and immune compartments mature and interact functionally during the postnatal development of the islet. We will focus on the juvenile maturation period because it is a stage during which early-arising autoimmunity is strongly correlated with the predisposition towards overt type 1 diabetes. The overarching hypothesis is that the onset of beta cell-directed autoimmunity is causally related to developmental alterations in the molecular phenotypes of islet cells and to changes in islet architecture. We propose that maturation processes make islets susceptible to inflammation and facilitate the development of autoimmunity. The rationale for the proposed research is that understanding what makes the islet vulnerable will not only help explain its downfall but also provide clues for intervention strategies. This project is thus relevant to the mission of the NIH and is responsive to the research objectives of the Funding Opportunity Announcement from the NIDDK entitled “High-Resolution Exploration of the Human Islet Tissue Environment”. Guided by preliminary data, we will test our hypothesis by pursuing three specific aims: (1) determine the mechanisms of functional maturation of islet endocrine cells, (2) determine how endocrine control of vascular function is established, and (3) determine changes in the phenotype and behavior of islet resident macrophages. Under the first aim, we will study the massive structural and functional changes needed for beta and alpha cells to reach their full secretory potential. In all three aims, we will record cellular responses with functional imaging and measure hormone release in living pancreas slices from donors aged 0 to 10 years old. These studies will be complemented by scRNA-seq analyses of cells sorted from isolated islets. Under the second aim, we will determine how the endocrine cells establish control of the vascular pericyte, the major regulator of blood flow in the islet. Under the third aim, we will examine how the phenotype and function of the islet resident macrophages changes during the maturation of the islet. The proposed research is significant because the anticipated results could reveal developmental processes that diminish the islet’s natural defenses and trigger abnormal responses from local immune cells. Knowing these processes is crucial to propose intervention targets aimed at preventing the development of type 1 diabetes.