We have been hearing about stem cells for years, but have always been told that stem cell technology is in the future. The future has arrived. Advanced Cell Technology, a company based in Santa Monica, Calif., is the sponsor for the first two clinical trials involving implanting stem cells in human eyes.
These trials are being conducted on patients with age-related macular degeneration in the United States and Stargardt’s disease in the United Kingdom. The clinical trial centers in the U.S. include the Jules Stein Eye Institute at UCLA School of Medicine in Los Angeles, Bascom Palmer Eye Institute in Miami, Wills Eye Institute in Philadelphia, and Mass Eye and Ear in Boston.
At Retina Consultants of Southwest Florida’s annual Eye Research Symposia earlier this year, Dr. Dean Eliott, the principal investigator at Mass Eye and Ear, spoke about his experience with stem cells. For more information about these clinical trials, please visit linicaltrials.gov.
The purpose of these early trials is to evaluate the safety and tolerability of stem cell implantation in humans. These two studies are expected to be completed by early 2014. Once stem cells are proven to be safe and tolerable by humans, additional clinical trials may begin to determine the effectiveness of stem cells on specific eye diseases.
Knowing the types of stem cells is essential in understanding stem cell research.
» Human Embryonic Stem Cells: These cells are taken from embryos from eggs that were fertilized in vitro, or in a laboratory. These cells are undifferentiated, or not assigned to become a specific cell type, so they can become any cell type. Diseases that may be treated with these types of stem cells include Parkinson’s disease, diabetes, muscular dystrophy, heart disease, traumatic spinal cord injury, vision and hearing loss, and much more. This type of stem cell is especially important in the field of retina research because it has potential to treat degenerative retinal diseases such as age-related macular degeneration, Stargardt’s Disease, retinitis pigmentosa, and a variety of other disorders.
» Adult/Somatic Stem Cells: These cells are taken from mature tissues. They may be found in the following tissues: brain, bone marrow, peripheral blood, blood vessels, skeletal muscle, skin, teeth, heart, digestive tract, liver, ovarian epithelium and testis. It was previously thought that these cells could only become cell types associated with the tissues they were taken from. Scientists are now working on ways to “reprogram” these types of stem cells to become undifferentiated like embryonic cells.
» Induced pluripotent stem cells: These are adult/somatic stem cells that have been reprogrammed, or undifferentiated. This is exciting news for two reasons: First, if these cells can be taken from a patient, and new tissue can be grown, then implanted into the same patient, the tissue will perfectly match that patient and will be less likely to be rejected. Second, this type of stem cell will eliminate controversy surrounding the use of human embryonic stem cells.
Scientists will continue to study all applications of stem cells, and will continue to learn and develop new strategies for treatment or cures, offering hope to patients with debilitating diseases such as age-related macular degeneration.