Models and Gene Therapies for AAT Deficiency

项目摘要（总体） α-1抗胰蛋白酶缺乏症（AATD）是由SERPINA 1基因突变引起的。的 E342 K（PI*Z）突变型等位基因在欧洲血统中非常常见，并且E342 K（PI*Z）突变型等位基因在欧洲血统中非常常见，并且E342 K（PI * Z）突变型等位基因在欧洲血统中非常常见。 纯合子编码分泌受损的蛋白质，导致AAT血清水平不足。 由于AAT通常保护肺中的弹性蛋白不被降解，因此有效AAT的丧失触发了 肺部炎症，气道阻塞和肺气肿，这是主要的生命限制 AATD的表现。本提案中的项目旨在寻求许多平行的 开发AATD基因治疗的策略。这些策略中的大多数都围绕着使用 基于重组腺相关病毒（rAAV）的载体，一种平台技术， 在其他遗传疾病的治疗上非常成功。在项目1中，将优化rAAV载体， 在基因定义的动物模型（包括小鼠和雪貂）中进行研究， 转基因重建研究使用调节条件转基因系统比较 两个相关的潜在目标替代水平（11µM和25µM）和临床相关 将研究终点。在项目2中，新型CRISPR变体将用于基因编辑， 基础编辑和主要编辑策略来治疗AATD。在项目3中，我们将自然筛选 从中国西部偏远人群中获得的AAV衣壳文库， 用于AATD基因治疗的功效和安全性增强的衣壳。在项目4中，我们将 使用新型Treg和CAR-Treg策略选择性调节抗载体免疫应答。 也将有两个核心。核心A将为每个项目提供重要的矢量 免疫学测定，其可以识别由于宿主对AAV的免疫应答而导致的限制 衣壳、AAT转基因或Cas9衍生蛋白。核心B将提供动物模型， 用于测试优化的rAAV载体、基因和/或其组合的动物模型中的生理学测量 编辑工具和免疫调节方法。项目调查人员有以下跟踪记录： 我们预计未来几年将继续进行互动和合作。

Project Summary (OVERALL) Alpha-1 antitrypsin deficiency (AATD) is caused by mutations in the SERPINA1 gene. The E342K (PI*Z) mutant allele is very common among those of European ancestry, and E342K homozygotes encode a protein with impaired secretion, resulting in deficient AAT serum levels. Since AAT normally protects elastin in the lung from degradation, loss of effective AAT triggers lung inflammation, airways obstruction and emphysema, which is the primary life-limiting manifestation of AATD. The projects within this proposal seek to pursue numerous parallel strategies to develop a gene therapy for AATD. Most of these strategies revolve around the use of recombinant adeno-associated virus (rAAV)-based vectors, a platform technology that has been very successful for other genetic diseases. In Project 1, optimized rAAV vectors will be studied in genetically defined animal models (including mice and ferrets) in comparison with transgenic reconstitution studies using a regulated conditional transgenic system to compare two relevant potential target replacement levels (11µM and 25µM) and clinically relevant endpoints will be studied. In Project 2, novel CRISPR variants will be used for gene editing, base editing and prime editing strategies to treat AATD. In Project 3, we will screen naturally occurring AAV capsid libraries obtained from remote populations in Western China to identify capsids with enhanced efficacy and safety for AATD gene therapy. Finally, in project 4, we will use novel Treg and CAR-Treg strategies to selectively modulate anti-vector immune responses. There will also be two cores. Core A will provide each project with important Vector Immunology assays, which can identify limitations due to host immune responses to AAV capsids, the AAT transgene or to Cas9-derived proteins. Core B will provide animal models and physiologic measurements in the animal models for testing of optimized rAAV vectors, gene editing tools and immune modulation approaches. Program investigators have a track record of interactions and collaborations that we anticipate will continue in future years.