WESTPORT, CT (Reuters Health) Apr 27 - Using a viral vector gene delivery technique, researchers have successfully restored sight in a canine model of Leber congenital amaurosis (LCA), a disease that causes near-total blindness in human infants.
In a study reported in the May issue of Nature Genetics, Dr. Jean Bennett, from the University of Pennsylvania in Philadelphia, and colleagues assessed the ability of gene therapy to restore vision in dogs with a naturally occurring mutation in the retinal pigment epithelium (RPE) 65 gene. Similar mutations have been seen in infants with LCA.
The researchers used a recombinant adeno-associated virus (AAV) vector to deliver the wild-type RPE65 gene to dogs. After intraocular injection of AAV-RPE65, various visual function tests confirmed that vision was, in fact, restored.
"A logical question leading from our results is whether subretinal injection of AAV-RPE65 would also correct the functional defects found in humans with LCA due to RPE65 mutations," the authors state. "Currently, there is no treatment for LCA and related early-onset retinal degenerative diseases."
Dr. Bennett's team believes that "if long-term preservation of structure despite loss of function is a feature of RPE-associated retinopathy, delivery of RPE65 to defective RPE cells could conceivably restore some functional vision to humans as well." ... |
