When it comes to designing stem-cell-based treatments for retinal diseases, Dennis Clegg, Ph.D., is one of the go-to researchers. He not only heads his own lab at the University of California at Santa Barbara; he’s the recipient of a CIRM grant for a treatment of age-related macular degeneration, and can turn complicated science into a compelling narrative, as this TED Talk demonstrates.
It’s thus no surprise that Dr. Clegg is part of an all-star research team designing a “retinal patch” project funded by FFB. He and I recently spoke about his work as well as the great promise of stem-cell research.
Please describe the “retinal patch” project and your role in it.
The idea is to generate a patch that would consist of a scaffold and two different retinal cell types that are sometimes missing in people with retinal diseases—photoreceptors and retinal pigment epithelium (RPE) cells. Both would be derived from induced pluripotent stem (iPS) cells, where you can take a skin biopsy and convert it into whatever kind of cell you need.
My group was the first to show you could make functional RPE cells from iPS cells. Now, we’re teaming up with Dr. David Gamm’s group, which will make the photoreceptors. Then we’ll try to combine them and basically rebuild the outer retina.
And you’re supervising another project, targeting AMD?
The FFB-funded project is really building on four years of another project using human embryonic stem cells to make RPE for the treatment of age-related macular degeneration. That’s a $20 million project funded by the California Institute for Regenerative Medicine, our state-funded stem-cell-research program. That project involves five universities, and our role, again, is to make the RPE cells.
We’re targeting the dry form of AMD, for which there is no treatment. We’ve been successful in a rat model, and we’re now carrying out crucial studies the FDA needs to see for an application for a Phase I clinical trial. We’re hoping to launch that at the end of 2014, beginning of 2015.
What motivates you to do this work?
There’s incredible potential in stem-cell research to treat blinding eye diseases. The eye is a really good place to develop cellular therapies, as compared to other tissues. Refined surgical techniques have already been developed, and the eye is easily accessible. Thanks to sophisticated imaging technology, there are also many ways to measure visual acuity to see if a treatment is working.
That’s compared to treating, say, a spinal cord injury, where you inject millions of cells into a spinal cord, and then it’s hard to know the results. The eye is a really good place to start.
It also seems as if stem-cell research is advancing relatively quickly.
It is. The first human embryonic stem cells were isolated in 1998, but these iPS cells were first described in humans in 2007, so that’s just a few years ago. And already we’re pushing toward clinical trials. In fact, in Japan, they’re going forward with a trial for the wet version of AMD. That’s the speed of light when it comes to scientific research, when you move so quickly from the basic level, discovery in a laboratory, to application in a clinical trial.
In developing retinal-disease treatments, what role does FFB play?
The Foundation’s role is crucial. It supports a lot of what’s called translational, or pre-clinical, research—what goes on before projects arrive in clinical trials. And to go from the basic discovery of making a cell in a lab to assembling all the data you need to present to the FDA for a clinical trial is an area where FFB provides support and basically moves the needle forward in very significant ways.
What do you foresee happening with potential treatments in the next decade?
It’s a very exciting time. Not only our group but a number of other groups are going forward with clinical trials using RPE cells for macular dystrophies. If you think about it, stem-cell research is similar to the space program in the 1960s—it’s the very early days, very experimental. We’re making these constructs and trying them out, and we don’t know which ones are going to be successful.
Different scaffolds are being tried, different cell lines, different types of applications. I think it’s a great way to go at it. It’s not going to happen overnight, but when we look back 10 years from now, we’re going to see at least one treatment getting into practice.
Pictured, above: Dr. Dennis Clegg