Stem Cell Research Races Toward the Clinic
Nov. 3, 2000 -- How close are researchers to solving the mysteries of paralysis? Close enough to believe it may happen, according to new research out of Johns Hopkins and other institutions around the country. In fact, through the use of what's called stem cells, scientists may be bearing down on treatments not only for some types of paralysis, but also for other conditions such as Parkinson's disease, stroke and traumatic brain injury.
Like a magician pulling a rabbit out of his hat, researchers are managing to rapidly generate large numbers of nerve cells -- neurons -- out of the most unlikely places, including adult bone marrow and even the brains of donors who have been dead for more than 20 hours. And if the cells can be shown to work in humans as they have in animals, they hold the promise for dramatic improvements of many conditions.
New research being unveiled this week at a meeting of neuroscientists in New Orleans show the many possible treatments that could be developed through the use of immature cells known as stem cells, which are now being coaxed in the lab to become different types of nerve cells. The process of causing a cell to mature into a specific type of cell is called differentiation.
Scientists at Johns Hopkins report, for instance, that they've restored movement of newly paralyzed mice and rats by injecting neural stem cells into the animals' spinal fluid. Fifty percent of these stem cell-treated rodents recovered the ability to place the soles of both or one of their hind feet on the ground.
Hopkins' researcher Jeffrey Rothstein, MD, PhD, says in a written statement that "this research may lead most immediately to improved treatments for patients with paralyzing motor neuron diseases such as amyotrophic lateral sclerosis [also called ALS or Lou Gehrig's disease] and another disorder, spinal motor atrophy."
These conditions are caused by disease and not injury. "Under the best research circumstances," Rothstein says, "stem cells could be used in early clinical trials within two years."
This is not the only advance being touted at the conference. Researchers admit to being both highly pleased and surprised by their ability to rapidly induce these cell changes.
"From multiple points of view it's extremely exciting when viewed from the bedside. When viewed from a basic science point of view of what we thought we knew about cell fates, cell commitment, and development, it's just as exciting," say Ira Black, MD, chairman of neuroscience at the Robert Wood Johnson Medical School in Piscataway, N.J.
In addition to providing investigators with new, potentially limitless sources of human stem cells, the discoveries promise to help stem-cell researchers steer their way around the roadblocks thrown in their paths by people who for religious or political reasons oppose the use of stem cells derived from human embryos.