Role of Bone Marrow-Derived Myeloid Cells in Alcohol Liver Disease

描述（由申请人提供）：晚期酒精性肝病（ALD）的唯一有效治疗方法是肝移植。因此，有必要更好地了解其发病机制，以促进治疗的发展。有证据表明，肝巨噬细胞（Macs）起着重要的作用;然而，迄今为止的研究尚未区分常驻Macs，枯否细胞（KCs），从浸润骨髓来源的髓样细胞（BMMC），在病理条件下补充KCs。我们检测了BMMCs，并将其与酒精处理的小鼠肝脏中的KCs区分开来。我们假设，在ALD期间招募到肝脏中的BMMCs根据ALD的微环境和严重程度呈现不同的表型和功能。拟议研究的具体目的是：（目的1），研究酒精处理导致肝脏BMMC蓄积的机制。a）收获来自乙醇喂养小鼠的肝脏以检查IL-1b、IL-6、S100 A8/A9、HSP 72和考克斯-2的信使表达水平。B）将通过使用中和抗体和IL-1 R-/-小鼠来研究IL-1 B和S100 A8/A9在BMMC的肝脏蓄积中的特异性参与。c）STAT 3 hep/-小鼠将用于检查酒精暴露后肝细胞特异性STAT 3信号传导在肝脏中BMMC积累中的作用。(Aim 2）、检测轻、晚期ALD患者骨髓基质细胞的表型和功能。a）用含5%乙醇的Lieber-Decarli饮食慢性喂养小鼠模拟轻度ALD。利用此模型，我们将研究骨髓基质细胞在促进酒精诱导的微循环障碍的修复中的功能，并检查VEGF和MMPs在介导这种功能中的作用。在这些研究中，将使用CD 11b-DTR小鼠和抗Gr-1抗体来消耗BMMC。B）其中用“西方饮食”随意喂养小鼠并灌胃注入乙醇的混合模型具有在小鼠中发现的酒精性脂肪性肝炎（ASH）和肝纤维化的特征。 晚期ALD患者。该模型将用于检查BMMC的表型，并研究其对肝损伤的贡献。(Aim 3）、探讨轻、晚期ALD患者BMMC表型的分子调控规律。a）将在ALD的混合模型中测量内毒素和损伤相关分子模式（DAMP）分子的全身和肝脏水平。B）通过给小鼠施用利福昔明抗生素和DAMP抑制剂来研究内毒素和DAMP对混合模型中BMMC的促炎性活化和肝损伤的贡献。c）将分别研究与轻度ALD和ASH相关的BMMC中的STAT 3活化和STAT 1/NF-kB活化。

DESCRIPTION (provided by applicant): The only effective treatment for advanced alcohol liver disease (ALD) is liver transplantation. It is imperative to better understand the pathogenesi in order to advance therapeutic development. Evidence suggests that hepatic macrophages (Macs) play an important role; however research to date has not distinguished resident Macs, Kupffer cells (KCs), from infiltrating bone marrow-derived myeloid cells (BMMCs), which replenish KCs during pathological conditions. We detected BMMCs and distinguished them from KCs in the liver of mice treated with alcohol. We hypothesize that the BMMCs recruited into the liver during ALD assume different phenotypes and functions, depending on the microenvironment and severity of ALD. The Specific Aims of the proposed studies are: (Aim 1), investigate the mechanisms of hepatic BMMC accumulation as result of alcohol treatment. a) Livers from ethanol-fed mice will be harvested to examine message expression levels of IL-1b, IL-6, S100A8/A9, HSP72, and COX-2. b) The specific involvement of IL-1b and S100A8/A9 in hepatic accumulation of BMMCs will be investigated by using neutralizing antibodies and IL-1R-/- mice. c) The STAT3hep/- mice will be utilized to examine the role of hepatocyte-specific STAT3 signaling in BMMC accumulation in the liver after alcohol exposure. (Aim 2), Determine the phenotypes and functions of BMMCs in mild and advanced ALD. a) Chronic feeding of mice with 5% ethanol-containing Lieber-Decarli diet simulates mild ALD. Using this model, we will investigate the function of BMMCs in promoting the repair of alcohol-induced microcirculation disorder, and examine the roles of VEGF and MMPs in mediating such function. The CD11b-DTR mice and anti-Gr-1 antibody will be employed to deplete BMMCs in these studies. b) A hybrid model, in which mice are fed ad libitum with "Western diet" and intragastrically infused with ethanol, shares characteristics of alcoholic steatohepatitis (ASH) and liver fibrosis found in patients with advanced ALD. This model will be employed to examine the phenotype of BMMCs, and investigate their contribution to liver injury. (Aim 3), Dissect the molecular regulations of BMMC phenotypes in mild and advanced ALD. a) The systemic and hepatic levels of endotoxin and damage-associated molecular pattern (DAMP) molecules will be measured in the hybrid model of ALD. b) The contributions of endotoxin and DAMPs to pro-inflammatory activation of BMMCs and liver damage in the hybrid model will be investigated by administering mice with rifaximin antibiotic, and inhibitors of DAMPs. c) STAT3 activation and STAT1/NF-kB activation in BMMCs associated with mild ALD and ASH, respectively, will be investigated.