Adeno-associated virus (AAV) packaging

Service introduction

        Adeno-associated virus (AAV) is a single-stranded DNA virus belonging to the Parvoviridae family. AAV can infect a variety of cells and is currently the leading tool for gene therapy.

        AAV is a defective virus that requires a helper virus (such as adenovirus or herpes simplex virus) to replicate and produce progeny AAV. AegiBio uses the helper-free AAV system to produce recombinant AAV without the need for a helper virus. In this system, the rep and cap genes are transferred from the viral vector to the helper plasmid pAAV-RC, while the AAV ITRs remain in the viral vector. The majority of the adenoviral gene products (including E2A, E4, etc.) required for AAV virion production are provided by the pHelper plasmid, while the remaining adenoviral gene products are provided by the host cells that stably express the adenoviral E1 gene. With the help of the helper plasmid, only the two ITRs at the ends are needed to package the exogenous fragment into the AAV virion. Therefore, the space left after the transfer of the rep and cap genes can allow the insertion of the exogenous gene into the viral genome.

Service advantages

        High safety: Recombinant AAV vectors (rAAV) are derived from non-pathogenic wild-type AAV. So far, no wild-type AAV that is pathogenic to humans has been found. The rAAV has also removed most of the wild-type AAV genome elements in the gene sequence, which further ensures safety.

        Low immunogenicity: The animal experiments cause little immune response.

        Wide host range: It can infect both dividing and non-dividing cells.

        Stable expression: It can mediate the long-term stable expression of exogenous genes in the body.

        Stable physical properties: It is resistant to chloroform and cannot be inactivated at 60℃.

Provided services

        AAV vector construction;

        Packaging of interfering AAV (shRNA and miRNA);

        Packaging of overexpressed AAV.

Provided products

Technical procedures

Tips

【Different serotypes of AAV virus vectors】

       Studies have found that AAV has many serotypes. The main difference between AAV vectors of different serotypes is the capsid protein. Before AAV enters the cell, it first binds to the corresponding receptor on the cell surface through the capsid protein and then attaches to the cell surface. Subsequently, through the interaction with other complex receptors, it initiates the biological activities of intracellular transport of viral particles. Therefore, different AAV serotypes have different affinities for different tissues and cells, which reflects the difference in transfection efficiency of AAV serotypes for different organs. Currently, AAV can be divided into 12 serotypes, AAV1-AAV12. AegiBio can select the AAV virus of the corresponding serotype for packaging according to the type of tissue or organ.