Discovering human cell-compatible gene therapy virus variants via optimized screening in mouse models

Area of Science:

• Gene Therapy
• Virology
• Molecular Biology

Background:

• Intravenous injection of viral vectors is the standard gene therapy administration route.
• Naturally occurring viruses used as vectors lack specific tissue tropism for targeted disease treatment.
• Adeno-associated viruses (AAVs) are common vectors but require improved organ specificity.

Purpose of the Study:

• To develop a method for rapidly generating adeno-associated virus (AAV) variants with enhanced organ targeting.
• To improve the safety and efficacy of gene therapy by reducing off-target infections.
• To create AAV variants that specifically target human liver cells.

Main Methods:

• Directed viral capsid evolution to engineer AAV variants.
• Utilizing organ-specific humanized mouse models for in vivo screening.
• Employing in vitro and in vivo virus screening to identify optimal variants.

Main Results:

• Successfully generated modified AAV variants with rapid, directed evolution.
• Demonstrated robust liver targeting, specifically favoring chimeric human liver cells over murine hepatocytes.
• Observed augmented targeting and reduced off-target organ infection in certain variants.

Conclusions:

• The developed process enables rapid engineering of tissue-specific viral vectors for gene therapy.
• Optimized AAV variants enhance safety and efficacy by improving target organ specificity and reducing off-target effects.
• This approach offers a significant advancement in tailoring gene therapy for specific diseases.