Receptor-guided AAV Tropism Engineering via MATCH.

Area of Science:

• Biochemistry
• Molecular Biology
• Gene Therapy

Background:

• Controlling viral tropism is crucial for effective gene delivery.
• Adeno-associated viruses (AAVs) are promising gene therapy vectors but lack precise targeting.
• Current methods for retargeting AAVs are often inefficient or lack control.

Purpose of the Study:

• To develop a modular method for programmable retargeting of AAVs.
• To enable site-specific covalent conjugation of targeting proteins to AAV capsids.
• To engineer AAV vectors with enhanced tropism for specific cell types and tissues.

Main Methods:

• Developed MATCH (Modulation of AAV Tropism through Conjugation to Homing proteins), a biochemical method using SpyTag/SpyCatcher system for protein conjugation.
• Incorporated SpyTag peptide into AAV capsid loops for site-specific attachment of SpyCatcher-linked targeting proteins.
• Utilized mosaic AAV-DJ and AAV9 capsids with controlled SpyTag incorporation for tunable ligand display.

Main Results:

• MATCH-AAVs conjugated to anti-CD3 antibodies efficiently transduced human T cells in vitro.
• TfR1-targeted MATCH-AAV9 showed up to an 84-fold increase in brain transduction in vivo compared to wild-type AAV9.
• Demonstrated receptor-dependent transduction and blood-brain barrier crossing with TfR1-targeted vectors.
• Developed a one-pot "Mix-and-MATCH" production strategy yielding functional, targeted AAVs.

Conclusions:

• MATCH provides a versatile and generalizable synthetic-biology approach for rational AAV tropism engineering.
• This method enables scalable production of custom AAV vectors for research and therapeutic applications.
• Programmed retargeting of AAVs via covalent protein conjugation offers a powerful tool for gene therapy development.