Modelling mechanisms of progressive chronic kidney disease in APOL1 high-risk live-donors using BAC-Transgenic mice

使用 BAC 转基因小鼠模拟 APOL1 高危活体供体的进行性慢性肾病的机制

• 批准号: 10726804
• 负责人: Shuta Ishibe
• 金额: $ 25.13万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10726804
• 关键词: APOL1 gene; Acceleration; Address; Affect; African ancestry; Age; Age Months; Albuminuria; Alleles; American; Antihypertensive Agents; Bacterial Artificial Chromosomes; Biochemical; Biological Models; Blood Pressure; Blood Pressure Monitors; Chronic; Chronic Kidney Failure; Clinical Data; Data; Development; Disease; Disparity; Doxycycline; Epidemiology; Excision; Focal and Segmental Glomerulosclerosis; Funding; Future; Genes; Genetic Transcription; Glomerulonephritis; Goals; Grant; Human; Hypertension; Immune; Immunologics; Inflammatory; Injections; Interferon Type II; Kidney; Kidney Diseases; Kidney Transplantation; Laboratories; Lesion; Light; Living Donors; Medicare; Modeling; Mus; Mutation; NPHS2 protein; Nephrectomy; Nephrons; Nucleic Acids; Pathogenesis; Patients; Phenotype; Physiological; Population; Positioning Attribute; Predisposition; Proteinuria; Public Health; Renal function; Research; Risk; Risk Factors; Role; Seminal; Sodium; Sodium-Restricted Diet; Source; Systemic blood pressure; T-Cell Activation; Telemetry; Testing; Therapeutic; Transgenic Mice; Transplantation; Variant; Viral; blood pressure elevation; catalyst; cohort; dietary salt; differential expression; disorder risk; feeding; follow-up; hemodynamics; high risk; high salt diet; human data; immune activation; improved; in vivo; inflammatory milieu; insight; kidney cell; morphometry; mouse model; novel; novel therapeutics; overexpression; podocyte; pre-clinical; promoter; pure line; risk variant; skills; systemic inflammatory response; tool

Technical Abstract Americans with African ancestry (AAs) make up 12-15% of the US population, but account for 35% of ESKD. This disparity is partly attributed to the carriage of exonic variants in APOL1 (G1, G2 risk alleles) within AAs, while all ancestries carry the major allele (G0). Only 10-15% with risk- genotype develop progressive CKD, suggesting “second hits” are needed. In kidney transplantation, the risk of progressive CKD in living donors (LDs) is a vital concern. Compared to white LDs, AA-LDs have a higher risk of CKD/ESKD along with increased risks of hypertension and inflammatory glomerulonephritis. Since the identification of APOL1-G1/G2 risk-genotypes, whether and how risk-genotype among AA-LDs contributes to the observed increased post- donation ESKD risk in AAs has remained a central question. In human LDs, significantly long follow-up times will be needed to understand actual donation-attributable risk with APOL1-variants. In light of these data, delineating the “second or third hits” that would modify disease risk in LDs with APOL1 risk-genotype, needs examination using a suitable model system. Here, we take advantage of our human BAC transgenic mice (BAC-Tg) expressing physiologic levels of APOL1 G0, G1, or G2 which we identify as recapitulating observed human immunologic and kidney phenotypes including CKD. We perform unilateral nephrectomy to model live donation, and specifically examine two putative second hit phenomena. In aim-1, we will test the hypothesis that nephrectomized G1- and G2- BAC-Tg develop hypertension-related progression of CKD. To induce hypertension in our mice, we will use models of dietary salt-loading, and also test sodium restriction as a therapeutic strategy. Detailed hemodynamic and histo-morphometric studies will provide mechanistic insight in this aim. Based on our recent identification of an immunologic role for APOL1-G1 and G2 variants, in Aim-2 we will mimic systemic immune activation in nephrectomized BAC-tg lines. Our goal here is to define the role and mechanism of Ifng-induced glomerulopathy in APOL1 BAC transgenic mice post-nephrectomy using novel doxycycline- inducible IFNG-expressing BAC-Tg lines. Novel Podocin rtTA TRAP mice will be utilized to identify differentially expressed genes to identify mechanisms in the pathogenesis of APOL1- induced FSGS, simultaneously comparing podocytes from uninephric and binephric mice. This proposal combines an array of different skill sets and unique tools to address critically important mechanistic and epidemiologic questions in transplantation, with the potential to reveal novel therapeutics for APOL1 - a profoundly unmet need.

技术摘要 非洲裔美国人 (AA) 占美国人口的 12-15%，但占 35% 的 ESKD 这种差异部分归因于 APOL1（G1， G2 风险等位基因）在 AA 内，而所有祖先都携带主要等位基因（G0），只有 10-15% 具有风险。 基因型发展为进行性 CKD，表明需要“第二次打击”。 移植后，活体供体 (LD) 进展性 CKD 的风险是一个至关重要的问题。 与白人 LD 相比，AA-LD 患 CKD/ESKD 的风险更高，同时患高血压的风险也更高 自从 APOL1-G1/G2 风险基因型的鉴定以来， AA-LD 中的风险基因型是否以及如何导致观察到的术后增加 AA 中的捐赠 ESKD 风险仍然是人类 LD 中的一个核心问题。 需要后续时间来了解 APOL1 变体的实际捐赠归因风险。 根据这些数据，描述将改变 LD 疾病风险的“第二次或第三次打击” 对于 APOL1 风险基因型，需要使用合适的模型系统进行检查。 我们的人类 BAC 转基因小鼠 (BAC-Tg) 表达生理水平的 APOL1 的优势 我们认为 G0、G1 或 G2 概括了观察到的人类免疫学和肾脏 表型包括 CKD。我们进行单侧肾切除术来模拟活体捐赠，以及 在目标 1 中，我们将具体检查两个假定的第二击现象。 肾切除的 G1- 和 G2- BAC-Tg 会导致高血压相关的 CKD 进展。 为了在我们的小鼠中诱发高血压，我们将使用饮食盐负荷模型，并测试钠 限制作为一种治疗策略将进行详细的血流动力学和组织形态学研究。 基于我们最近对免疫作用的鉴定，提供了这一目标的机制见解。 对于 APOL1-G1 和 G2 变体，在 Aim-2 中，我们将模拟系统免疫激活 我们的目标是明确 Ifng 诱导的肾切除 BAC-tg 系的作用和机制。 使用新型强力霉素治疗 APOL1 BAC 转基因小鼠肾切除术后肾小球病 新型 Podocin rtTA TRAP 小鼠将用于表达可诱导的 IFNG 的 BAC-Tg 小鼠。 鉴定差异表达基因以确定 APOL1- 发病机制 诱导 FSGS，同时比较非肾病和双肾病小鼠的足细胞。 该提案结合了一系列不同的技能和独特的工具来解决关键问题 移植中的重要机制和流行病学问题，有可能揭示 APOL1 的新疗法——这是一个尚未得到满足的需求。

项目成果

Advancing mouse models for transplantation research.

推进移植研究的小鼠模型。

• 发表时间: 2024-01-12
• 作者: Cravedi, Paolo;Riella, Leonardo V;Ford, Mandy L;Valujskikh, Anna;Menon, Madhav C;Kirk, Allan D;Alegre, Maria;Alessandrini, Alessandro;Feng, Sandy;Kehn, Patricia;Najafian, Nader;Hancock, Wayne W;Heeger, Peter S;Maltzman, Jonathan S;Mann
• 通讯作者: Mann