The ability to accurately measure small improvements in visual function is critical now that researchers are beginning to evaluate experimental therapies in humans. In response to the need for standardized visual function tests, The U.S. Foundation Fighting Blindness has been working with leading visual assessment experts to formulate standards for measuring visual function in low vision patients. Such standards will enable the research community to ensure the therapeutic results of experimental treatments like retinal cell transplants are real and verifiable. Another challenge facing transplantation is the need for identifying suitable donor tissue sources. At the symposium, Foundation-funded work was presented showing that transformed RPE cells can delay photoreceptor degeneration and limit deterioration of vision when transplanted into an animals model.
Transformed cells have the ability to reproduce themselves in large quantities in culture.
If transplantation becomes a viable treatment option for patients, the demand for donor cells will require an abundant supply. Transformed cells may provide such a supply. While it is disappointing that these first transplants have not yet demonstrated conclusive success in halting or delaying vision loss or in restoring lost vision, these experiments have helped immeasurably in further defining the remaining obstacles confronting this experimental therapy. The questions that these human transplant studies raise will clearly drive the next generation of laboratory experiments. The Foundation remains optimistic that from continued laboratory and clinical research, effective therapies can emerge.