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 非洲血统的美国人（AAS）占美国人口的12-15％，但占 ESKD的35％。这种差异部分归因于Apol1中的外显子变体载体（G1， G2风险等位基因）在AAS内，而所有祖先都带有主要等位基因（G0）。只有10-15％的风险 - 基因型会发展为渐进式CKD，建议需要“第二击”。在肾脏 移植，生物捐助者（LDS）的进行性CKD的风险是至关重要的问题。比较的 对于白色LDS，AA-LDS的CKD/ESKD风险较高，高血压风险增加 和炎症性肾小球肾炎。由于鉴定了apol1-g1/g2风险基因型，因此 AA-LDS之间的风险基因型以及如何促进观察到的增加之后的增加 AAS中的ESKD风险仍然是一个核心问题。在人类LD中，很长 需要进行后续时间来了解Apol1变化的实际捐赠局部风险。 鉴于这些数据，描绘了“第二次或第三次命中”，以改变LDS的疾病风险 使用APOL1风险基因型，需要使用合适的模型系统进行检查。在这里，我们接受 我们的人类BAC转基因小鼠（BAC-TG）的优势表达Apol1的生理水平 G0，G1或G2，我们识别为概括性观察到的人类免疫学和肾脏 包括CKD在内的表型。我们进行单侧肾切除术以模拟实时捐赠，并 在AIM-1中，我们将检验以下假设 CKD的肾切除型G1-和G2-BAC-TG发育与高血压相关的进展。到 在我们的小鼠中诱导高血压，我们将使用饮食中的盐载型，并测试钠 限制是一种治疗策略。详细的血流动力学和组织术研究将 在此目标中提供机械洞察力。根据我们最近对免疫学作用的识别 对于Apol1-G1和G2变体，在AIM-2中，我们将模仿全身免疫激活 肾脏切除型BAC-TG系。我们的目标是定义IFNG诱导的作用和机制 新型强力霉素 - 可诱导IFNG的BAC-TG系。新型的Podocin RTTA陷阱小鼠将用于 识别不同表达的基因，以鉴定Apol1-发病机理中的机制 诱导的FSG，仅比较了单脑和二元小鼠的足细胞。 该提案结合了各种不同技能和独特工具，以解决批判性地解决 移植中的重要机械和流行病学问题，有可能揭示 APOL1的新型疗法 - 深刻未满足的需求。