Cell Transplants for Macular Degeneration
From the MIT Technology Review: "Rats genetically engineered to lose their sight can be protected from blindness by injections of human neural stem cells ... a startup in Palo Alto, CA, plans to use the positive results to file for approval from the U.S. Food and Drug Administration to begin human trials. The company is already testing the cells in children with a rare, fatal brain disorder called Batten's disease. ... The company's cells are isolated from human fetal tissue and then grown in culture. To determine whether these cells can protect against retinal degeneration, scientists studied rats that were genetically engineered to progressively lose their photoreceptors - cells in the retina that convert light into neural signals. These animals are commonly used to model macular degeneration and retinitis pigmentosa, two major causes of blindness that result from cell loss in the retina. Researchers injected about 100,000 cells into the animals' eyes when the rats were 21 days old. ... the cells migrate over time, forming a layer between the photoreceptors and a layer of tissue called the retinal pigment epithelium, cells which nourish and support the photoreceptors. ... the cells protected vision in the part of the retina in which they were implanted."
Link: http://www.technologyreview.com/biomedicine/25647/?a=f