Protein Carrier Adeno-Associated Virus

Area of Science:

• Molecular Biology
• Biotechnology
• Gene Therapy

Background:

• Adeno-associated virus (AAV) is a key vector for gene therapy, primarily delivering DNA.
• The capacity of AAV to deliver protein payloads remains largely unexplored.
• Expanding AAV's utility requires novel delivery mechanisms beyond nucleic acids.

Purpose of the Study:

• To engineer a protein-carrying AAV (pcAAV) capable of packaging and delivering protein payloads.
• To investigate the efficiency and factors influencing protein packaging within AAV capsids.
• To demonstrate the therapeutic potential of AAV-mediated protein delivery.

Main Methods:

• Engineered AAV capsids by inserting binding domains on the interior surface.
• Mediated protein packaging via interactions between binding domains and protein tags during capsid assembly.
• Validated packaging of diverse proteins including fluorescent proteins, Cas9, Cre recombinase, and APEX2.
• Assessed packaging efficiency based on insertion site, viral protein isoform, and target protein localization.

Main Results:

• Successfully demonstrated packaging of multiple proteins within engineered AAV capsids.
• Showcased that packaging efficiency is influenced by specific engineering strategies and protein characteristics.
• Confirmed successful cellular entry and protein payload delivery by pcAAV.
• Verified that delivered enzymes retained their biological activity post-packaging.
• Established that this protein packaging capability is applicable across multiple AAV serotypes.

Conclusions:

• Adeno-associated virus (AAV) has been successfully engineered as a versatile protein delivery vehicle (pcAAV).
• This advancement significantly broadens the scope of AAV applications in biomedical research and therapy.
• pcAAV technology opens new avenues for protein-based therapeutics and diagnostics.