Growth in technology and intellectual capital has made cell-based therapies a potent weapon in the fight against blindness.
“When I think of stem-cell-based therapies and technology, the word ‘momentum’ is paramount. In many ways, we’ve beaten the curve to this point.”
That’s Dr. David Gamm, a clinician-researcher whose career began not long after Dr. James Thomson, a colleague at the University of Wisconsin, discovered a way to grow human embryonic stem cells — cells that can be coaxed into becoming any kind of human tissue — in 1998. Several years later, Dr. Thomson derived what are called induced pluripotent stem cells, or iPS cells, from adult blood. Now, with Foundation funding, he, Dr. Gamm and others are hard at work turning iPS cells into potentially vision-restoring retinal cells.
There are two reasons for this turn of events. “One, scientific technology has grown exponentially, with sophisticated techniques and concepts evolving,” Dr. Gamm, M.D., Ph.D, explains. “And, two, very talented individuals are entering the field.” The Foundation, he adds, is a leader in facilitating stem cell research targeting retinal diseases. “That’s part of its history — identifying promising areas and getting in right off the bat, so it can initiate and maintain momentum.”
In 2013, the Foundation awarded Dr. Gamm and his team $900,000 to develop a “retinal patch,” a two-layered set of stem cells designed to replace two types of cells damaged by various retinal diseases — photoreceptors and retinal pigment epithelial (RPE) cells. Says Dr. Gamm: “The analogy I like to use is, if your car doesn’t run and you don’t have pistons or a carburetor, putting just a carburetor or pistons back in isn’t going to get it to run. You need both.”
Fixing a retina, however, isn’t as simple. In stem cell research, there are three broad areas of momentum at present, according to Dr. Gamm: cell manufacture, cell installation and therapy evaluation. The first is farthest along, with RPE, in particular, “a relatively easy cell type to grow,” he says. But mixing RPE cells with photoreceptors, then installing them in the retina “and having them survive, make the right connections and continue to function — a lot of work needs to be done.” And evaluation comes into play only after installation.
Thankfully, many labs worldwide are working hard on the installation challenge, with each one learning from the others. Dr. Gamm expects major advancements within the next 10 years.
Another notable area of stem cell research receiving Foundation funding is disease modeling. Because iPS cells are derived from skin or blood, “samples from people affected by retinal diseases are sent to us,” Dr. Gamm explains. iPS cells are then created, directed to turn into retinal cells and placed in a dish, where they’re tested with various treatments. Only those that work will be shuttled toward clinical trials. “So instead of just shooting from the hip,” Dr. Gamm says, “we can customize therapies based on the actual dysfunctions that are going on at the cellular level.”
With so many stem cell options, Dr. Gamm is reminded of the Foundation’s “diversified portfolio” approach to fighting blindness — one featuring not just stem cell, but gene and drug therapies too. “The Foundation,” he says, “does a great job applying the right amount of emphasis to different fields and identifying new ones.”