Novel human liver-tropic AAV variants define transferable domains that markedly enhance the human tropism of AAV7 and AAV8

Marti Cabanes-Creus; Renina Gale Navarro; Erhua Zhu; Grober Baltazar; Sophia H Y Liao; Matthieu Drouyer; Anais K Amaya; Suzanne Scott; Loan Hanh Nguyen; Adrian Westhaus; Matthias Hebben; Laurence O W Wilson; Adrian J Thrasher; Ian E Alexander; Leszek Lisowski

doi:10.1016/j.omtm.2021.11.011

Novel human liver-tropic AAV variants define transferable domains that markedly enhance the human tropism of AAV7 and AAV8

Mol Ther Methods Clin Dev. 2021 Nov 25:24:88-101. doi: 10.1016/j.omtm.2021.11.011. eCollection 2022 Mar 10.

Authors

Marti Cabanes-Creus¹, Renina Gale Navarro¹, Erhua Zhu², Grober Baltazar¹, Sophia H Y Liao¹, Matthieu Drouyer¹, Anais K Amaya², Suzanne Scott^{2

3}, Loan Hanh Nguyen¹, Adrian Westhaus^{1

4}, Matthias Hebben⁵, Laurence O W Wilson³, Adrian J Thrasher⁴, Ian E Alexander^{2

6}, Leszek Lisowski^{1

7

8}

Affiliations

¹ Translational Vectorology Research Unit, Children's Medical Research Institute, The University of Sydney, Westmead, NSW 2145, Australia.
² Gene Therapy Research Unit, Children's Medical Research Institute & The Children's Hospital at Westmead, The University of Sydney, Westmead, NSW 2145, Australia.
³ Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW 2113, Australia.
⁴ Great Ormond Institute of Child Health, University College London, WC1N 1EH London, UK.
⁵ LogicBio Therapeutics, 65 Hayden avenue, Lexington, 02421 MA, USA.
⁶ Discipline of Child and Adolescent Health, The University of Sydney, Sydney Medical School, Faculty of Medicine and Health, Westmead, NSW 2145, Australia.
⁷ Vector and Genome Engineering Facility, Children's Medical Research Institute, The University of Sydney, Westmead, NSW 2145, Australia.
⁸ Military Institute of Medicine, Laboratory of Molecular Oncology and Innovative Therapies, 04-141 Warsaw, Poland.

Abstract

Recent clinical successes have intensified interest in using adeno-associated virus (AAV) vectors for therapeutic gene delivery. The liver is a key clinical target, given its critical physiological functions and involvement in a wide range of genetic diseases. Here, we report the bioengineering of a set of next-generation AAV vectors, named AAV-SYDs (where "SYD" stands for Sydney, Australia), with increased human hepato-tropism in a liver xenograft mouse model repopulated with primary human hepatocytes. We followed a two-step process that staggered directed evolution and domain-swapping approaches. Using DNA-family shuffling, we first mapped key AAV capsid regions responsible for efficient human hepatocyte transduction in vivo. Focusing on these regions, we next applied domain-swapping strategies to identify and study key capsid residues that enhance primary human hepatocyte uptake and transgene expression. Our findings underscore the potential of AAV-SYDs as liver gene therapy vectors and provide insights into the mechanism responsible for their enhanced transduction profile.

Keywords: AAV; adeno-associated vectors; bioengineered vectors; bioengineering; gene therapy; liver-tropic; preclinical liver model; recombinant vectors; xenograft model.