Adeno-Associated Virus & Retinal Gene Transfer

Adeno-Associated Virus (AAV) is a non-pathogenic, single-stranded DNA genome-containing, helper virus-dependent member of the parvovirus family. AAV particles are non-enveloped, icosahedral and small (~26 nm in diameter), and wild-type AAV has never been shown to cause disease in humans or animals.Recombinant AAV can be used to efficiently and stably deliver foreign genes to ocular cells. There are a number of different serotypes of AAV that have been identified and serotype 2, AAV2, was the first to be tested in retinas of animals and humans. AAV2 is the serotype that is being used in clinical trials for Leber's Congenital Amaurosis (LCA) due to RPE65 mutations, Choroideremia and age-related macular degeneration. Subretinal delivery of AAV2 appears to be safe using the doses that have been tested to date, and there are signs of efficacy in the studies of LCA. Members of CAROT have played key roles in carrying out the preclinical safety and efficacy studies and designing and carrying out the clinical trials for LCA-RPE65 that are taking place at the Children's Hospital of Philadelphia (CHOP).  CAROT is also carrying out the preclinical studies necessary to use AAV2 to launch gene therapy clinical trials for Choroideremia and other diseases.

While AAV2 appears useful and safe, there may be other AAV serotypes which will expand opportunities for targeting additional retinal diseases. CAROT plays a major role in evaluating novel AAV serotypes and is also engineering AAVs which may be uniquely suited to treat specific forms of blinding disease.

CAROT sponsors a retina-specific AAV Research Core Facility under the directorship of Shangzhen Zhou