Researchers Just Made a Historic Breakthrough in Stem Cell Research

The news: The medical journal Lancet published a game-changing study Wednesday that has huge implications for the entire field of stem cell therapy.

In the first-ever human embryonic stem cell study approved by the Food and Drug Administration and carried out on human subjects, researchers treated 18 patients with two incurable eye conditions — age-related macular degeneration (the most common cause of vision loss in people over age 60) and Stargardt macular degeneration — over a three-year period. While the goal of the study was to evaluate the safety of stem cell transplants, researchers discovered that the procedure was also effective, with the majority of patients reporting significantly improved eyesight.

The successful trials mean scientists have provided the first evidence that stem cells from human embryos can be a safe and effective source of therapies for eye diseases.

"Our results suggest the safety and promise of stem cells to alter progressive vision loss in people with degenerative diseases and mark an exciting step towards using embryonic stem cells as a safe source of cells for the treatment of various medical disorders," study leader Steven Schwartz of the Jules Stein Eye Institute told the Telegraph.

This is huge for the future of stem cell research. While critics have plenty of moral objections to stem cell therapy, there are medical concerns as well. Because stem cells come from other donors and can grow into any cell type, there is the possibility that, after the procedure, those treated could develop tumors or have an autoimmune reaction.

But the Lancet study was designed to prevent the latter scenario, as the transplants took place in the eye's retinal space, which has no immune cells. The patients received injections of 50,000 to 150,000 retinal pigment cells — created from stem cells donated from in vitro fertilization procedures — and were given medication to suppress their immune systems. And the fact that patients not only avoided dangerous side effects but benefited from the procedure bodes well for future stem cell research.

"This is the first report showing that the cells are safe in the long term and that they can actually help people," Robert Lanza, chief scientific officer at Advanced Cell Technology, which funded the study, told CNN. "You can turns these into insulin-producing cells for diabetes, heart cells to treat heart disease. They can be turned into nerve cells to treat Alzheimer's disease or Parkinson's disease or stroke."

And of course, it's also good news for the patients. The fact that the study exceeded the researchers' expectations means that many of the study participants have experienced an improvement in their quality of life. "Our goal was to prevent further progression of the disease, not reverse it and see visual improvement," Lanza said. "But seeing the improvement in vision was frosting on the cake."

Human trials of stem cell therapy are still few and far between. But the positive results of this study will hopefully allow more in the future.