Other Key AMD-Related Research Initiatives
Complement Factor H (CFH) gene — In early 2005, FFB-funded researchers identified variations in a gene known as CFH, which are implicated in as many as 50 percent of all cases of AMD. In early 2006, these same investigators found that variations in CFH along with variations in two other newly identified genes, factor B (BF) and complement component (C2), are present in 74 percent of AMD cases.
Though the environmental and genetic causes of AMD are complex and not completely understood, these landmark findings confirm a genetic influence on the development of AMD. And, these genes give a clear target for the development of future, more effective therapies. Specifically, the CFH finding strongly suggests that the immune system and related inflammatory responses are key factors in the development of AMD. Future therapies may be directed toward stopping the effects of CFH variations and other related genes.
Scientists believe more AMD–related genes will be identified in the near future. FFB continues to fund genetic research for AMD, because the identification of genetic risk factors will give experts the best targets for preventions and cures.
FFB’s Stem Cell Consortium — FFB oversees a consortium of investigators working to advance the development of stem cell therapies to regenerate retinal tissue, and restore vision in people significantly affected by AMD and other retinal degenerative diseases. Stem cell therapies also show promise as neuroprotective treatments, providing protection for the remaining, functioning photoreceptors of people affected by AMD and other diseases.
Though stem cell treatments are still at an early stage of development, they are a key priority of The Foundation, because of their overwhelming potential to save and restore vision.
Some background on stem cells: A stem cell is an immature cell that has the potential to become any number of cells in organs and tissue, including photoreceptors and other retinal components. Theoretically, a stem cell can replicate indefinitely, yielding an unlimited supply of cells.
Therapeutic stem cells can be derived from a variety of sources including: bone marrow, embryos, umbilical cord blood (after child birth), and a variety of adult human organs and tissue.
One of the challenges in developing stem cell treatments is prodding the immature cells to become vital, functioning photoreceptors and other mature cells. Also, researchers must ensure that the immune system of the recipient doesn’t reject the transplanted cells.
Retinal transplantation — A Phase II human study of retinal transplantation is in progress for people with severe vision loss, including those affected by AMD. Though the investigation is still at an early stage, researchers are making encouraging progress. The researchers are perfecting the procedure for transplanting delicate retinal tissue, minimizing tissue rejection, and testing methods to get the transplanted retinas to integrate with the recipients’ tissues.
Artificial retinas (retinal chips) — Though still in the early stage of development, artificial retinas offer hope for people who have lost all or most of their vision from advanced retinal degenerative diseases, including AMD. Numerous retinal chip studies are underway throughout the world. Most of these studies are investigating the optimal location of the chip within the eye, as well as the chip’s long-term viability and compatibility with existing tissue.
Most artificial retinas are being designed to replace lost photoreceptors and other retinal tissue. The artificial devices are designed to convert light into images, and send them back to the brain via the optic nerve.
One device, designed by Mark Humayan, M.D., Ph.D., Doheny Eye Institute, University of California, Los Angeles, is in a human clinical trial, and is enabling patients to see light and basic shapes. This device includes a video camera, which is mounted on a pair of glasses. Images from the camera are relayed to the artificial chip, which in turn sends them to the optic nerve. Humayan’s device is modeled after the cochlear implant, which gives a rudimentary hearing capability to people who are deaf. Humayan and his colleagues are working on a new model of the device, which should improve the recipient’s ability to perceive detail. FFB funded early studies of this artificial retina.