Tom Reh, PhD
Our lab is focused on the development and repair of the retina, the light sensitive tissue of the eye. We apply the information we obtain from our developmental studies to develop methods for retinal repair using human embryonic stem cells, induced pluripotent cells, or through the stimulation of endogenous repair mechanisms. We have been particularly interested in the role of the Notch signaling pathway in retinal development and repair. We have developed methods for directing human ES cells to a retinal progenitor fate, and are exploring the molecular mechanisms that further restrict their identity to rod and cone photoreceptors. We have found that transplantation of photoreceptors derived from human ES cells can restore light response to mice with congenital blindness. Although our studies in amphibians and birds have shown that endogenous repair mechanisms can regenerate retinal cells in non-mammalian vertebrates, recent work from the lab also demonstrates a limited potential for the endogenous repair of the retina after damage, from a population of support cells known as Muller glia. We are working to determine the molecular mechanisms that limit their capacity for regeneration in mammals by determining their differences from non-mammalian vertebrates.