Hydrogel-mediated co-transplantation of retinal pigmented epithelium and photoreceptors restores vision in an animal model of advanced retinal degeneration.

We demonstrate a novel approach to reverse advanced stages of blindness using hydrogel-mediated delivery of retinal pigmented epithelium (RPE) and photoreceptors directly to the degenerated retina of blind mice. With sodium iodate (NaIO3) injections in mice, both RPE and photoreceptors degenerate, resulting in complete blindness and recapitulating the advanced retinal degeneration that is often observed in humans. We observed vision restoration only with co-transplantation of RPE and photoreceptors in a hyaluronic acid-based hydrogel, and not with transplantation of each cell type alone as determined with optokinetic head tracking and light avoidance assays. Both RPE and photoreceptors survived significantly better when co-transplanted than in their respective single cell type controls. While others have pursued transplantation of one of either RPE or photoreceptors, we demonstrate the importance of transplanting both cell types with a minimally-invasive hydrogel for vision repair in a degenerative disease model of the retina.