# Therapeutic Application and Structural Features of Adeno-Associated Virus Vector

## TL;DR

This paper discusses how adeno-associated virus (AAV) is used in gene therapy and the structural features important for its effectiveness and safety.

## Contribution

The paper emphasizes the importance of understanding AAV capsid structure and receptor interactions to improve gene therapy safety and efficacy.

## Key findings

- AAV uses proteoglycans as receptors, but different sugar chains affect binding.
- Understanding capsid structure and receptor modifications is crucial for biopharmaceutical efficacy.
- Improving gene transfer efficiency and reducing non-target cell infection is necessary for safer therapies.

## Abstract

Adeno-associated virus (AAV) is characterized by non-pathogenicity, long-term infection, and broad tropism and is actively developed as a vector virus for gene therapy products. AAV is classified into more than 100 serotypes based on differences in the amino acid sequence of the capsid protein. Endocytosis involves the uptake of viral particles by AAV and accessory receptors during AAV infection. After entry into the cell, they are transported to the nucleus through the nuclear pore complex. AAVs mainly use proteoglycans as receptors to enter cells, but the types of sugar chains in proteoglycans that have binding ability are different. Therefore, it is necessary to properly evaluate the primary structure of receptor proteins, such as amino acid sequences and post-translational modifications, including glycosylation, and the higher-order structure of proteins, such as the folding of the entire capsid structure and the three-dimensional (3D) structure of functional domains, to ensure the efficacy and safety of biopharmaceuticals. To further enhance safety, it is necessary to further improve the efficiency of gene transfer into target cells, reduce the amount of vector administered, and prevent infection of non-target cells.