Preclinicai studies utilizing different AAV serotypes have demonstrated efficient gene transfer in animal models and stable correction of hemophilia in murine and canine models has been achieved. Early clinical trial data suggest that achievement of therapeutic levels of clotting factors is feasible in human subjects. However, the latter clinical trials have also underscored two major challenges, namely, a large patient cohort displaying pre-existing humoral immunity against AAV capsids and potential hepatotoxiclty associated with administration of high vector dose. The current proposal is focused on designing next generation AAV vectors that display potentia! to evade preexisting anti-capsid neutralizing antibodies (NAbs) and transduce human hepatocytes with high efficiency. To achieve such, we will utilize three complementary AAV capsid engineering techniques and two translational components, namely, a mouse model with humanized fiver and human serum containing anti-AAV capsid NAbs. In synergy with Project 1 of this PPG, we will first establish the hepatotropism of AAV clades with rationally altered antigenic epitopes in humanized mice. In the second and third aims, we will utilize a novel chemical engineering strategy and a combinatorial directed evolution approach, respectively to mask the antigenicity of hepatotropic AAV vectors. The proposed studies should (a) provide structural insight into the antigenicity and hepatotropism of AAV vectors, (b) humanized AAV vectors for preclinical evaluation in large animal models of hemophilia (Projects 3 &4) and (c) optimized vector candidates for clinical trials.

Public Health Relevance

Eariy clinical trial data suggest that gene therapy of bleeding disorders might be feasible in human subjects. The current proposal is focused on tackling clinically relevant challenges, namely preexisting neutralizing antibodies and the need for humanized AAV vectors validated in translational animal models. This project will enable development of new AAV vectors simultaneously capable of enhanced gene transfer to human liver and escaping nrefixistina humoral immunitv in human subjects.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Research Program Projects (P01)
Project #
Application #
Study Section
Heart, Lung, and Blood Program Project Review Committee (HLBP)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of North Carolina Chapel Hill
Chapel Hill
United States
Zip Code
Chai, Zheng; Samulski, R Jude; Li, Chengwen (2018) Nab Escaping AAV Mutants Isolated from Mouse Muscles. Bio Protoc 8:
Sun, Junjiang; Shao, Wenwei; Chen, Xiaojing et al. (2018) An Observational Study from Long-Term AAV Re-administration in Two Hemophilia Dogs. Mol Ther Methods Clin Dev 10:257-267
Chai, Zheng; Zhang, Xintao; Rigsbee, Kelly Michelle et al. (2018) Cryoprecipitate augments the global transduction of the adeno-associated virus serotype 9 after a systemic administration. J Control Release 286:415-424
Tse, Longping V; Moller-Tank, Sven; Meganck, Rita M et al. (2018) Mapping and Engineering Functional Domains of the Assembly-Activating Protein of Adeno-associated Viruses. J Virol 92:
Albright, Blake H; Storey, Claire M; Murlidharan, Giridhar et al. (2018) Mapping the Structural Determinants Required for AAVrh.10 Transport across the Blood-Brain Barrier. Mol Ther 26:510-523
Tse, Longping Victor; Klinc, Kelli A; Madigan, Victoria J et al. (2017) Structure-guided evolution of antigenically distinct adeno-associated virus variants for immune evasion. Proc Natl Acad Sci U S A 114:E4812-E4821
Liang, Katharine J; Woodard, Kenton T; Weaver, Mark A et al. (2017) AAV-Nrf2 Promotes Protection and Recovery in Animal Models of Oxidative Stress. Mol Ther 25:765-779
Wang, M; Sun, J; Crosby, A et al. (2017) Direct interaction of human serum proteins with AAV virions to enhance AAV transduction: immediate impact on clinical applications. Gene Ther 24:49-59
Chai, Zheng; Sun, Junjiang; Rigsbee, Kelly Michelle et al. (2017) Application of polyploid adeno-associated virus vectors for transduction enhancement and neutralizing antibody evasion. J Control Release 262:348-356
Berry, Garrett E; Tse, Longping V (2017) Virus Binding and Internalization Assay for Adeno-associated Virus. Bio Protoc 7:

Showing the most recent 10 out of 46 publications