The retina is a thin layer of tissue lining the back of the eye. In humans, more than 80 percent of sensory information is acquired through vision. Many blinding diseases such as age-related macular degeneration (AMD) and glaucoma, involve the permanent loss of retinal cells, especially the light-sensing photoreceptors or the retinal ganglion cells, which connect the retina to the brain. Currently, there is no effective treatment to replenish these lost cells and to repair the damaged retinas. Recent advancements in stem cell technology have enabled scientists to propagate and coax pluripotent stem cells to develop into retinal cells that can potentially be used for this repair. However, despite the progress, major challenges remain to produce the desired cell types on demand, and to efficiently integrate these stem cell-derived neurons into a pre-existing retinal neural circuit. The proposed research will study how naïve, non-committed stem cells progressively develop into photoreceptor cells and ganglion cells, two of the most-often damaged retinal neuronal types. The investigation will combine advanced molecular genetic technologies and stem cell cultures to monitor retinal cell differentiation more effectively and to optimize conditions that promote photoreceptor and ganglion cell production. Knowledge gained from these studies will enhance our abilities to control the production of retinal cell types for integration and repair of diseased retinas.
Blinding eye diseases have devastating effects on human perception and daily activities. According to the Centers for Disease Control and Prevention (CDC), approximately 80 million people in the United States have eye diseases that could lead to vision loss. Thus, vision loss is among the top ten disabilities affecting the health and well being of Americans. The State of California is one of the most populated states in the United States and thus has vast patient population afflicted with various forms of vision loss. For example, over 215,00 people are afflicted with age-related retinal degeneration (AMD) in California now. The rising cost of healthy care and social services required to treat these and other blinding eye diseases thus creates an enormous burden to individual California citizens, as well as to the overall Californian economy. Stem cell therapies aimed at restoring vision in these patients would not only improve the patient care that California can offer its citizens, but also enhance and strengthen the leading position of California in ocular stem cell research and clinical therapy. The proposed research, with the help of CIRM funding, seeks to gain fundamental knowledge about stem cell-derived retinal precursor cells that will be crucial for developing these stem cell-based replacement and repair therapies.