Mingling life imaging and cell subpopulations expression analysis in NHP lungs targeted with exosome associated double AAV vectors

The National Institute of Allergy and Infectious Diseases awarded the Regents of the University of Minnesota a $437,250 Project Grant under the Allergy and Infectious Diseases Research program (CFDA 93.855) on June 25, 2025, with completion targeted for May 31, 2027. This research initiative focuses on advancing gene therapy delivery for lung-specific diseases by evaluating adeno-associated virus (AAV) vector systems packaged within extracellular vesicles. The project combines non-invasive in vivo imaging techniques with post-necropsy analysis to assess AAV-mediated gene expression in airway cell subpopulations, particularly basal stem cells, using non-human primate models to evaluate feasibility and safety prior to clinical translation.

The deliverables encompass comprehensive mechanistic data and technical characterization of exosome-associated double AAV vector efficacy in achieving clinically relevant gene transfer to airway epithelium. By leveraging the University of Minnesota's research capabilities and facilities in Minnesota, the project will generate critical preclinical evidence regarding transduction efficiency, cell-type specificity, and long-term transgene expression patterns to support the development of improved gene therapy approaches for patients with genetic or acquired lung disorders.

Abstract

Gene therapy provides a universal therapeutic option for patients with genetic or acquired disorders that can potentially benefit a broad patient populations. However, up to date several gene therapy clinical trials for lung- specific diseases, while well addressing safety concerns, have failed to demonstrate clear therapeutic benefits among the participated patients. This dismal reality is most likely attributed to the inability to achieve clinically- relevant gene transfer efficacy in the airway epithelium, and particularly to airway basal stem cell or basal cell. Recently, we have demonstrated the ability of AAV serotype 6 (AAV6) vectors to achieve widespread and efficient transgene expression in the human airway epithelial cell (AEC) in in vitro and in the mouse models in vivo. Importantly, subsets of the lung cell, such as basal cells, were targeting that provides anticipation for possible long-term gene expression in highly renewable layer of airways. Additionally we showed in our most recent published collaborative studies higher transduction efficiency over commonly used aavs by extracellular vesicles associated AAV (EV-AAV) to the mouse lungs and human AEC cultured in air-liquid interface conditions. The large cargo of average EVS (100-200 NM) allows accumulation of multiple AAV particles (20-25 NM), and, unlike AAV, EVS enter cells multiple by ways that do not depend on receptor abundance. These important findings lead to the development of current proposal that combines non-invasive in vivo imaging with post-necropsy analysis of AAV-mediated gene expression in subpopulations of airway cells in non-human primates (NHP) model. NHP models play a critical role in feasibility and safety modeling for the development of therapeutics. The mechanistic underpinning is expected to provide critical information for the design of next-generation gene therapy vectors targeting lung, which can be used for wide range of pulmonary diseases required reliable expression of therapeutic modalities across airways.