AAV5-CAG-NLuc-2A-mCherry

Recombinant adeno-associated viruses (rAAV) are promising viral vectors for gene delivery applications. These viruses belong to the single-stranded DNA (ssDNA) packaged Parvoviridae and Dependovirus genera. Hundreds of AAV genotypes have been sequenced from multiple mammalian species, and to date, 12 serotypes (AAV1 to AAV12) have been defined for human and non-human primate isolates. Based on antigenic reactivity and sequence similarity, these 12 serotypes can be divided into eight genotypes, clades A to F, and clonal isolates AAV4 and AAV5. These groups are represented by AAV1 to AAV9, with AAV1 and AAV6 belonging to the same clade A due to their high sequence similarity and antigenic cross-reactivity. The sequence identity of representative members is approximately 55% to 99%, with AAV4 and AAV5 being the most divergent from each other and from other members.

Transgenes packaged in the prototypical human serotype AAV2 have been effective in correcting genetic diseases of the eye, brain, muscle, liver, and lung in animal models and have been successfully used to treat blindness and muscular dystrophy in humans. However, other serotypes have shown improvements in gene delivery related to the capsid sequence in certain tissues compared to AAV2. For example, in studies packaging the same transgene, AAV5 was more effective than AAV2 in transducing neurons and lung tissue. At the apical surface of airway epithelial cells, AAV5 was 20-fold and 50-fold more potent than AAV2 in vivo and in vitro, respectively, and was as effective as AAV8 in expressing coagulation factor IX systemically for the treatment of hemophilia. These observations have fueled efforts to develop AAV5 as a vector for the treatment of genetic diseases.