Syn-Cre-GFP AAV (Serotype Retrograde)

Viral vectors are an important tool for introducing transgenes into specific neuronal populations and are by far the best choice for achieving targeted genetic access to projection neurons by entering axon terminals and transporting their payload retrogradely to the nucleus. Many naturally evolved neurotropic viruses exhibit retrograde transmission during their life cycle, including rabies virus, poliovirus, and herpes simplex virus (HSV). Among them, rabies virus is particularly neuroinvasive and spreads rapidly in the nervous system via transcellular transfer. However, its potential for biological research and gene therapy has been hampered by its high toxicity, although efforts are underway to reduce its toxicity. Recombinant adeno-associated viruses (rAAVs) have emerged as an effective platform for in vivo gene therapy because they mediate high levels of transgene expression, are nontoxic, and elicit minimal immune responses. These properties were central to the decision to approve the first full approval of rAAV-mediated gene therapy for lipoprotein lipase deficiency. rAAVs have shown great promise in clinical trials for a range of neurological diseases and are one of the most widely used vectors in neuroscience research. Since the initial discovery that AAVs can undergo retrograde transport, rAAVs have been able to retrogradely access projection neurons of specific circuits to a limited extent. AAV serotype retrograde delivery systems can be used alone or in combination with Cre recombinase driver lines to achieve long-term, high-level transgene expression sufficient to effectively interrogate neural circuit function and perform genome editing in targeted neuronal populations.