A World Spinning Fast from Stem Cells
News last week that Japanese scientists had discovered a much easier way of reprogramming cells into an embryonic state was too late to make it on to Science Channel’s fascinating “Stem Cell Universe” hosted by Stephen Hawking Feb. 4.
But it just goes to show you how fast the field is moving.
As if we weren’t aware of it already, the television special reminds us that we are on the brink of a new age of medicine, one that allows us to dream of using stem cells not just to grow new tissue but perhaps entire organs. Or to coax the thousands of cable-like axons in spinal nerve cells to extend far enough so that severed spinal cords can be reconnected—and paralysis reversed. Or to store our own stem cells at an early age—and use them later on to help renew and repair the cells that cause us to age. Or to re-engineer harvested cells from cadavers to build artificial organs, an idea that Doris Taylor of the Texas Heart Institute has done in rats. By applying decellurization Taylor’s lab siphoned off all of the cells from a dead organ and then seeded the protein scaffold left behind with stem cells matched to the donor. Taylor believes this approach may allow us to create artificial organs that can circumvent the long-term threat of tissue rejection that organ recipients now face.
Ten or 20 years ago, these experiments would have all sounded like material for a sci-fi flick, now some of the best minds of science think we may be on the cusp of a new way of treating disease, and inarguably one of the brightest minds in science is promoting the advances on a cable channel. Forward-thinking or overly-optimistic? Certainly, research funders are encouraged. A recent report by EuroStemCell, which was formed in 2010 to unite more than 90 European stem cell and regenerative medicine labs, finds that stem cell research sector is growing more than twice as fast (7%) as the global research average (2.9%). The report looked at the growth and development of the stem cell field as a whole, including embryonic stem (ES) cell and induced pluripotent stem (iPS) cell research.
Despite a crippling recession and Congressional gridlock that have kept government spending flat in recent years, the US National Institutes Health—the largest public funder of biomedical research in the world—also cites encouraging numbers, though who knows if this trend can continue. The agency is expected to spend more on stem cell research in fiscal year 2014—about $1.3 billion—than it did in 2009 (about a $1 billion.)
The California Institute of Regenerative Medicine (CIRM) is also helping pave the path to clinical translation of stem cells by not only providing strategic funding from the $3 billion that was appropriated in 2004 for California-based stem cell research but by also providing education resources, scientific guidance and creating partnerships with industries and resources for stem cell researchers.
And within Big Pharma, New Jersey-based giant Johnson & Johnson announced earlier last month that it planned to purchase a $12.5 million option in a small California-based biotech that recently went public. Capricor Therapeutics is about start a Phase II study of a new, potentially more efficient stem cell therapy approach that relies on alogeneic stem cells from donors to regenerate damaged hearts. As reported in Fierce Biotech, it is rare for BigPharma to “gamble on a field that is trying to make a comeback.”
The fact that researchers continue to make game-changing strides in how to make stem cells viable in the lab—including last week’s groundbreaking studies in Nature1,2 describing the induction of pluripotency in cells from a newborn mouse without the use of extrinsic transcription factors, chemical manipulation or nuclear transfer—is reason to be optimistic that stem cell therapies might be more widely commercialized in the not-too-distant future. Researchers were able to induce pluripotency without having to introduce foreign DNA—the researchers did it by stressing the adult cells in an acid bath.
Rosalba Sacca, director, scientific development at Charles River and an expert in genetically engineered mouse models, said advances like this might one day open the door to wider use of in vitro tests for human cell models—where cells from patients are the target of the candidate drug compound—and less reliance on animal models.
But for all the promise of stem cells and stem cell-based, we cannot lose sight of potential safety concerns of these long-term and sometimes irreversible therapies—a point that got a bit lost in the Science Channel special—and the importance of determining the best way to predict these risks before use in humans. “The fact is that issues of safety are still unresolved,” said Shawna Jackman, Senior Research Scientist in the Photobiology and Cellular Therapeutic Safety group at Charles River’s Preclinical Services site in Horsham, Pa. Jackman notes that regulatory agencies are balancing potential benefits with potential risks when providing regulatory oversight for these unique products as the industry and requirements for safety assessments evolve. The FDA finalized the first specific guidance for cell therapies last fall to provide recommendations for preclinical safety assessments prior to clinical trials.
Hawking, who notes he was born too soon to enjoy this “Golden Age of Science,” cautions that big science discoveries like these carry much power—but also great risk. Whether stem cells become the magic bullet or a ticking time bomb is a matter of debate, though Hawking clearly remains optimistic.
Nature 505 doi:10.1038/nature12968 2014
Nature 505 doi:10.1038/nature12969 2014