Syn-jGCaMP7c AAV (Serotype 9)

Adeno-associated virus (AAV) was first discovered in 1965 and was considered a "biological curiosity" but has continued to fascinate a small number of researchers. AAV is a single-stranded DNA virus that is non-pathogenic to humans, has low immunogenicity but high transduction efficiency, and is incapable of self-replication. Recombinant AAV (rAAV) can stably express gene products, either from unintegrated episomes in quiescent tissues or by integration into actively dividing tissues, provided that they are engineered with appropriate homology arms. After determining the complete nucleotide sequence, molecularly cloning the wild-type (WT) AAV genome, and demonstrating the remarkable ability of WT AAV to site-specifically integrate AAV DNA into the long arm of human chromosome 19 (19q13.3), two independent research groups subsequently developed the first recombinant AAV vectors. Further improvements have followed, and interest in this vector system has continued to grow exponentially over the past two decades. Following the first approval of rAAV therapy for the U.S. market, rAAV gene therapy and passive vaccines have rapidly gained attention and investment. Nearly 200 rAAV clinical trials for various indications have been completed, and many investigational new drug applications are under various stages of review by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA). AAV vectors have been used to treat a variety of human diseases, such as Leber's congenital amaurosis, lipoprotein lipase deficiency, hemophilia B, aromatic L-amino acid decarboxylase deficiency, choroideremia, Leber's hereditary optic neuropathy, hemophilia A, and spinal muscular atrophy, with unexpectedly significant clinical efficacy. Multiple AAV serotypes are now available, and they have shown clinical efficacy in animal models for a variety of human diseases.