Role of macrophage evolution in hepatic adaptation to alcohol.

项目标题：巨噬细胞进化在肝脏酒精适应中的作用 项目摘要/摘要 急性酒精性肝炎(AH)是一种由酗酒引发的严重炎症性肝病。这种病 30天内的死亡率约为20%。AH最显著的特征之一是它只影响 少数酗酒者表明，大多数人都受到保护，不会患上酒精性肝脏 疾病的机制尚不清楚。我们最近的研究表明，小鼠暴露在酒精环境中会导致早期 肝巨噬细胞(M-Φ)群的改变，库普弗细胞损失高达50%，并进入浸润性 巨噬细胞。10天后，Kupffer细胞数量恢复，但它们的基因表达模式 更像是抗炎的M2巨噬细胞。酒精暴露35天后，肝脏M-Φ基因的表达 随着一些经典的M2标记的减少和基因的发育，模式进一步变化 与恢复性MΦ表型相关的表达模式。巨噬细胞数量的变化与 肝脏对脂多糖挑战的敏感度发生变化。我们假设“丢失的”库普弗细胞 迅速被“适应性”巨噬细胞取代，导致肝脏炎症最小。这 适应性巨噬细胞的形成需要库普弗细胞来源的凋亡小体和Th2细胞因子，如IL4 和IL13。促炎和抗炎M-ΦS的平衡与肝脏适应性M-Φ群体的性质 随着时间的推移发生变化，因此在长期接触酒精的情况下，可能会失去适应性，肝脏可能会发炎 发生。更好地了解适应性巨噬细胞的性质和导致其 酒精性肝病的形成、维持和丢失将为酒精性肝病的治疗提供新的途径。我们 我将以以下具体目标探索这一假说：目标1：确定起源、基因表达 酒精暴露后出现的小鼠肝脏MΦ亚型的模式和功能特性。 我们将使用谱系追踪技术和单细胞RNA测序来确定 巨噬细胞群存在。然后我们将分离适应性巨噬细胞群以确定它们的 体内和体外的功能特性。目标2：定义负责生产和生产的信号 维持酒精适应性M-Φ种群。我们将研究特定的凋亡小体的作用 受体，不同来源的凋亡体的影响，肝内凋亡体形成的时间， 以及肝细胞衍生因子在适应性巨噬细胞群形成中的作用。目标3：实现 确定促进人类酒精适应的巨噬细胞/单核细胞群。这些 实验将利用小鼠在前两个目标中的发现来识别酒精适应性巨噬细胞 人类中的种群。这将通过对肝脏尸检中巨噬细胞的免疫组织化学分析来完成。 非饮酒者和长期饮酒者无肝病的标本，以及患者的肝脏组织 患有酒精性肝炎。这些将与这些患者组中的循环血单核细胞进行比较，最终 将与从酒精性肝硬变患者肝移植外植体中分离的巨噬细胞进行比较 与酒精无关的病因所致的肝硬变。这些研究将增强我们对巨噬细胞如何 表型变化保护肝脏免受酒精的影响，将识别导致这些变化的信号，并将 定义哪些变化可以保护人类免受酒精性肝病的侵袭。这项研究的长期目标是 发展巨噬细胞导向疗法调整酒精性肝炎的病程并增强抗病毒作用 在广泛的炎症性肝病中具有炎症和组织修复作用。

PROJECT TITLE: Role of macrophage evolution in hepatic adaptation to alcohol PROJECT SUMMARY / ABSTRACT Acute alcoholic hepatitis (AH) is a severe inflammatory liver disease triggered by binge drinking. The disease has a 30-day mortality of approximately 20%. One of the most striking features of AH is that it affects only a small minority of heavy drinkers suggesting that most individuals are protected from developing alcoholic liver disease by as yet unknown mechanisms. We have recently shown that alcohol exposure in mice causes early changes in liver macrophage (MΦ) populations with a loss of up to 50% of Kupffer cells and entry of infiltrating macrophages. By 10 days, Kupffer cell numbers are restored but their gene expression patterns have become more like anti-inflammatory M2 macrophages. By 35 days of alcohol exposure, the hepatic MΦ gene expression pattern changes further with a decrease in some of the classic M2 markers and the development of a gene expression pattern associated with a restorative MΦ phenotype. The macrophage population changes correlate with changes in the sensitivity of the liver to a challenge with LPS. We hypothesize that the “lost” Kupffer cells are rapidly replaced by “adaptive” macrophages leading to a state in which liver inflammation is minimal. This adaptive macrophage formation requires Kupffer cell-derived apoptotic bodies and Th2 cytokines such as IL4 and IL13. The balance of pro-and anti-inflammatory MΦs and the nature of the hepatic adaptive MΦ populations change over time so that with prolonged alcohol exposure, adaptation can be lost and liver inflammation can occur. Better understanding of the nature of the adaptive macrophages and the factors that lead to their formation, maintenance and loss would provide new approaches for the therapy of alcoholic liver disease. We will explore this hypothesis with the following specific aims: Aim 1: To determine the origins, gene expression patterns and functional properties of the mouse liver MΦ subtypes that appear after alcohol exposure. We will use lineage tracing techniques and single cell RNA sequencing to define the origin and diversity of the macrophage populations present. We will then isolate the adaptive macrophage populations to determine their functional properties both in vivo and in vitro. Aim 2: To define the signals responsible for production and maintenance of alcohol adaptive MΦ populations. We will examine the role of specific apoptotic body receptors, the impact of different sources of apoptotic bodies, timing of apoptotic body formation within the liver, and the role of hepatocyte derived factors in the formation of adaptive macrophage populations. Aim 3: To identify macrophage/monocyte populations that contribute to alcohol adaptation in humans. These experiments will leverage the mouse findings made in the first two aims to identify alcohol adaptive macrophage populations in humans. This will be done by immunohistochemical analysis of macrophages in liver autopsy specimens from non-drinkers and chronic alcohol drinkers without liver disease, and liver explants from patients with alcoholic hepatitis. These will be compared to circulating blood monocytes in these patient groups and finally will be compared with macrophages isolated from liver transplant explants of patients with alcoholic cirrhosis and cirrhosis due to etiologies unrelated to alcohol. These studies will enhance our knowledge of how macrophage phenotype changes protect the liver from alcohol, will identify the signals responsible for these changes and will define which changes protect humans from alcoholic liver disease. The long-range goal of this research is to develop macrophage directed therapies to modulate the course of alcoholic hepatitis and enhance anti- inflammatory and tissue restorative effects in a wide range of inflammatory liver diseases.