Macrophages and attenuation of inflammation resolution in APOL1 nephropathy

APOL1 肾病中巨噬细胞和炎症消退的减弱

• 批准号: 10624214
• 负责人: Jennie J LIn
• 金额: $ 62.76万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-20 至 2027-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10624214
• 关键词: Acceleration; Address; Affect; African Trypanosomiasis; African ancestry; Alleles; American; Anti-Inflammatory Agents; Apolipoproteins; Apoptotic; Attenuated; Automobile Driving; Biological Factors; Biological Models; Biology; Black race; Cells; Cholesterol Homeostasis; Chronic; Chronic Kidney Failure; Coculture Techniques; Code; Complex; Cytokine Signaling; DNA; Development; Disease; Disease Progression; End stage renal failure; Endoplasmic Reticulum; Functional disorder; Genes; Genetic Transcription; Genetic study; Genotype; Goals; Health Care Costs; Homeostasis; Human; Human Genetics; Immune; Immune response; Impairment; In Vitro; Individual; Inflammation; Inflammatory; Injury; Injury to Kidney; Innate Immune Response; Interferon Type II; Interleukin-10; Interleukin-4; Investigation; Kidney; Kidney Diseases; Link; Macrophage; Measures; Mediating; Mitochondria; Modeling; Molecular Chaperones; Natural Immunity; Pathogenesis; Pathway interactions; Patients; Phagocytes; Phenotype; Play; Primates; Process; Proteins; Quality of life; Reactive Oxygen Species; Resolution; Respiration; Risk; Risk Factors; Role; Signal Transduction; Signaling Protein; Sterility; Stimulus; Stress; Testing; Therapeutic; Tissues; Transgenic Mice; United States; Validation; Variant; Work; attenuation; biological adaptation to stress; cell type; comorbidity; disease phenotype; endoplasmic reticulum stress; experience; genome editing; genomic locus; health difference; high risk; immune function; in vivo; induced pluripotent stem cell; inhibitor; insight; kidney cell; kidney fibrosis; kidney repair; lipid metabolism; metabolic abnormality assessment; mitochondrial dysfunction; mitochondrial metabolism; mortality; novel; pathogen; podocyte; protein activation; protein function; response; response to injury; risk variant; socioeconomics; tissue repair; transcriptomics

PROJECT SUMMARY Individuals who self-identify as Black in the United States experience disproportionately higher rates of developing chronic kidney disease (CKD) and experiencing CKD progression to end-stage kidney disease (ESKD). A portion of this health difference is not explained by socioeconomic and traditional risk factors, necessitating the study of other biological factors contributing to disease pathogenesis. Human genetics studies have identified and validated two common coding variants in the primate-specific Apolipoprotein L1 (APOL1) gene that contribute to high rates of proteinuric CKD in patients with African ancestry. These alleles, termed G1 and G2, evolved and became common due to the survival advantage they confer against African trypanosomiasis. Despite their role in primate innate immunity, not much is known about the role immune cells such as macrophages, which contribute to kidney injury and repair, play in APOL1 nephropathy. To address this gap, we propose to use genome-edited induced pluripotent stem cell (iPSC) derived macrophages and transgenic mice to investigate how G1 and G2 APOL1 alter macrophage function to promote kidney disease. We focus on the macrophage due to its dual role in innate immune responses to pathogens and contribution to kidney injury and fibrosis. In preliminary studies, we have generated genome-edited G1 iPSCs sharing an isogenic background with G0 controls and found that G1 iPSC derived macrophages maintain higher expression of proinflammatory genes under multiple conditions. Because chronic sterile macrophage inflammation can drive kidney disease, we are investigating mechanisms by which G1 and G2 APOL1 promote a sustained proinflammatory macrophage phenotype and maladaptive tissue repair. In various complex diseases including CKD, resolution of tissue inflammation requires anti-inflammatory reprogramming of immune cells and clearance of apoptotic cells by macrophages via efferocytosis. Additionally, macrophage inflammation can be induced by stress or dysfunction of the endoplasmic reticulum (ER), which has been implicated in APOL1 biology in other cell types. Therefore, we hypothesize that G1 and G2 macrophages undergo impaired anti-inflammatory reprogramming and inefficient efferocytosis through enhanced ER stress, thereby contributing to non-resolving kidney inflammation and APOL1 nephropathy. To test this central hypothesis, we will delineate which ER stress pathways G1 and G2 APOL1 perturb (Aim 1), investigate anti-inflammatory signaling and mitochondrial dysfunction in the attenuation of reparative reprogramming of G1 and G2 macrophages (Aim 2), and determine the mechanisms by which G1 and G2 APOL1 impair efferocytosis (Aim 3). The proposed investigations will test a novel hypothesis that APOL1 risk alleles amplify kidney injury through macrophage dysfunction. Elucidating the macrophage’s role in APOL1 nephropathy will offer critical insight for developing complementary strategies to treat APOL1 disease through enhancing macrophage-mediated tissue repair.

项目概要 在美国，自认为是黑人的个人经历的比例要高得不成比例。 患有慢性肾病 (CKD) 并经历 CKD 进展为终末期肾病 （ESKD）。这种健康差异的一部分无法用社会经济和传统风险因素来解释， 需要研究导致疾病发病机制的其他生物因素。人类遗传学研究 已鉴定并验证了灵长类动物特异性载脂蛋白 L1 (APOL1) 中的两个常见编码变体 导致非洲血统患者蛋白尿 CKD 发生率高的基因。这些等位基因，称为 G1 和 G2，由于相对于非洲人具有生存优势而进化并变得普遍 锥虫病。尽管免疫细胞在灵长类动物先天免疫中发挥着重要作用，但人们对免疫细胞的作用知之甚少 例如巨噬细胞，它有助于肾脏损伤和修复，在 APOL1 肾病中发挥作用。 为了解决这一差距，我们建议使用基因组编辑的诱导多能干细胞（iPSC）衍生的 巨噬细胞和转基因小鼠研究 G1 和 G2 APOL1 如何改变巨噬细胞功能以促进 肾脏疾病。我们关注巨噬细胞，因为它在对病原体的先天免疫反应中发挥双重作用， 导致肾损伤和纤维化。在初步研究中，我们已经生成了基因组编辑的 G1 iPSC 与 G0 对照共享同基因背景，发现 G1 iPSC 衍生的巨噬细胞保持较高水平 多种条件下促炎基因的表达。因为慢性无菌巨噬细胞 炎症可能导致肾脏疾病，我们正在研究 G1 和 G2 APOL1 促进的机制 持续的促炎巨噬细胞表型和适应不良的组织修复。在各种复杂疾病中 包括 CKD 在内，组织炎症的解决需要免疫细胞的抗炎重编程和 巨噬细胞通过胞吞作用清除凋亡细胞。此外，巨噬细胞炎症还可 由内质网 (ER) 的应激或功能障碍引起，这与 APOL1 生物学有关 在其他细胞类型中。因此，我们假设 G1 和 G2 巨噬细胞的抗炎功能受损 通过增强内质网应激而导致重编程和低效的胞吞作用，从而导致非解决性问题 肾脏炎症和 APOL1 肾病。为了检验这个中心假设，我们将描述哪些 ER 压力 通路 G1 和 G2 APOL1 扰乱（目标 1），研究抗炎信号传导和线粒体 G1 和 G2 巨噬细胞修复性重编程减弱功能障碍（目标 2），并确定 G1 和 G2 APOL1 损害胞吞作用的机制（目标 3）。拟议的调查将测试 一种新的假设，即 APOL1 风险等位基因通过巨噬细胞功能障碍放大肾损伤。阐明 巨噬细胞在 APOL1 肾病中的作用将为制定补充策略提供重要见解 通过增强巨噬细胞介导的组织修复来治疗 APOL1 疾病。