AAV (Adeno-Associated Virus) capsids library refers to a collection of genetically engineered AAV capsids that are used for research and applications related to AAV-based gene delivery and gene therapy.

AAV is a small, non-pathogenic virus that has gained significant interest in the field of gene therapy due to its ability to efficiently deliver genetic material into cells. The AAV capsid is the protein shell that surrounds the viral genome and plays a crucial role in determining the tropism (cellular targeting) and transduction efficiency of AAV vectors.

The library enables researchers to screen and select AAV capsid variants with desired characteristics for specific applications. For example, they can search for capsids with improved tissue tropism, enhanced transduction efficiency, reduced immunogenicity, or altered payload capacity. By testing different capsids from the library, researchers can optimize AAV vectors for targeted gene delivery to specific cell types or tissues.