Cabanes-Creus Marti, Navarro Renina Gale, Liao Sophia H Y, Baltazar Grober, Drouyer Matthieu, Zhu Erhua, Scott Suzanne, Luong Clement, Wilson Laurence O W, Alexander Ian E, Lisowski Leszek
Translational Vectorology Research Unit, Children's Medical Research Institute, The University of Sydney, Westmead, NSW 2145, Australia.
Gene Therapy Research Unit, Children's Medical Research Institute and The Children's Hospital at Westmead, The University of Sydney, Westmead, NSW 2145, Australia.
Mol Ther Methods Clin Dev. 2021 Apr 24;21:607-620. doi: 10.1016/j.omtm.2021.04.010. eCollection 2021 Jun 11.
Recent successes in clinical gene therapy applications have intensified the interest in using adeno-associated viruses (AAVs) as vectors for gene delivery into human liver. An inherent intriguing characteristic of AAVs is that vector variants vary substantially in their ability to transduce hepatocytes from different species. This has historically limited the value of preclinical studies using rodent models for predicting the efficiency of AAV vectors in liver-targeted gene therapy clinical studies. In this work, we aimed to investigate the key determinants of the observed differential interspecies transduction abilities among AAV variants. We took advantage of domain swapping strategies between AAV-KP1, a newly identified variant with enhanced murine liver tropism, and AAV3b, which functions poorly in mice. The systematic comparison of AAV3b/AAV-KP1 chimeric variants allowed us to identify a threonine insertion at position 265 within variable region I (VR-I) as the key residue that confers murine hepatic transduction to human-derived clade B (AAV2-like) and clade C (AAV3b-like) variants. We propose to use this insertion to generate phylogenetically related AAV surrogates in support of toxicology and dosing studies in the murine liver model.
临床基因治疗应用的近期成功加剧了人们对使用腺相关病毒（AAV）作为将基因递送至人肝脏的载体的兴趣。AAV的一个内在有趣特征是载体变体在转导不同物种肝细胞的能力上有很大差异。这在历史上限制了使用啮齿动物模型进行临床前研究以预测AAV载体在肝靶向基因治疗临床研究中的效率的价值。在这项工作中，我们旨在研究AAV变体间观察到的种间转导能力差异的关键决定因素。我们利用了AAV-KP1（一种新鉴定的具有增强的小鼠肝脏嗜性的变体）和在小鼠中功能不佳的AAV3b之间的结构域交换策略。对AAV3b/AAV-KP1嵌合变体的系统比较使我们能够确定可变区I（VR-I）中第265位的苏氨酸插入是赋予人源B类（AAV2样）和C类（AAV3b样）变体小鼠肝脏转导能力的关键残基。我们建议使用这种插入来生成系统发育相关的AAV替代物，以支持在小鼠肝脏模型中的毒理学和剂量研究。
