EyeWorld Asia-Pacific March 2018 Issue

22 EWAP FEATURE March 2018 a donor that otherwise would have too low of an endothelial cell count to be transplanted. Dr. Mehta said their research has shown the ability to expand cells almost 240-fold. “With that number, it allows you to take one donor cornea and make enough cells to treat 90 patients. Now we have something that could be a cell therapy ap- proach,” he said, and “you’ve alle- viated this issue on donor stress.” Preliminary research for this technique involved establishing the best media to create a proliferative, morphologically sound endothelial monolayer. 12 Dr. Mehta said they now use two different types of me- dia to culture cells, one for expan- sion and the other to stabilize the morphology of the cells. Animal testing has shown successful re-endothelialization with cultivated human donor cells, delivered either on a carrier or via injection. 13–14 For the car- rier method, endothelial cells are cultivated on a thin slice of human tissue—a biodegradable carrier is also in the works, Dr. Mehta said— and implantation and postopera- tive protocol follows exactly as in a DSEK. For injection, the patient’s Descemet’s is left intact, but Dr. Mehta uses a specially designed instrument (ASICO, Westmont, Il- linois) to scrape off the endothelial cells. From there, the cultivated en- dothelial cells are injected and the patient lays face down for 3 hours. Dr. Mehta said there are certain indications where one technique might be favored over the other. For example, patients with no bul- lous keratopathy, no Descemet’s scarring could fare well with cell injection, while a patient with a lot of central guttae would be better with cultivated cells transplanted on a carrier. While culturing endothelial cells is resource intensive, Dr. Me- hta said they performed analysis to determine the actual cost of cul- tured endothelial cell transplants vs. traditional donor transplants. 15 He said even if the number of pos- sible cultured cells from one donor could only treat 60–70 patients, the cost to treat one cornea in this way is about $400, compared to $3,000 for a full donor cornea. “A lot of countries don’t have access to tissue, but even if you do have access, that’s still a significant reduction in cost,” he said. Alternative - from page 21