Expertise in Adeno Associate Virus Packaging

AAV introduction

AAV is a small linear single-stranded DNA parvovirus with a diameter of 20 nm, a molecular weight of 3.9 MegaDaltons, and 60 monomers of VP1, VP2, and VP3 in a ratio of 1:1:10. It is replication-deficient and has traditionally required co-infection with a helper adenovirus or herpes virus for replication and infection.  Its advantages include being non-pathogenic and low immunogenic to humans. It also has high transduction efficiency and long-term transgenic expression and broad host range including both dividing and none-dividing cells. These advantages make AAV a most promising tool for gene therapy and biomedical research.

AAV genome

AAV genome is about 4.7 kilobases long comprised of inverted terminal repeats (ITRs), rep and cap.  Rep proteins are required for AAV genome replication and Cap proteins are composed of virus capsid.

AAV packaging

We are currently using PEI to co-transfect pAAV, pAAV-RC, and pHelper into HEK 293A cells to package AAV. We are conducting iodixanol gradient ultracentrifugation or precipitate and PEG / aqueous two-phase partitioning to produce higher titer and purity AAV vectors. We also provide heparin or AVB affinity purification upon customer request.