NEW YORK — A few months ago, Dr. Thomas Einhorn was treating a patient with a broken ankle that wouldn't heal, even with multiple surgeries. So he sought help from the man's own body.
Einhorn drew bone marrow from the man's pelvic bone with a needle, condensed it to about four teaspoons of rich red liquid and injected that into the man's ankle.
Four months later, the ankle was healed. Einhorn, chairman of orthopedic surgery at Boston University Medical Center, credits "adult" stem cells in the marrow injection. He tried it because of published research from France.
Einhorn's experience isn't a rigorous study. But it's an example of many innovative therapies doctors are studying with adult stem cells — cells typically taken from bone marrow and blood, not embryos.
For all the emotional debate that began about a decade ago on allowing the use of embryonic stem cells, it's adult stem cells that are in human testing today. An extensive review of stem-cell projects and interviews with two dozen experts reveal a wide range of potential treatments.
Adult stem cells are being studied in people who suffer from multiple sclerosis, heart attacks and diabetes. Early results suggest stem cells can help some patients avoid leg amputation.
Recently, researchers reported they restored vision to patients whose eyes were damaged by chemicals.
Apart from these efforts, transplants of adult stem cells have become a standard life- saving therapy for perhaps hundreds of thousands of people with leukemia, lymphoma and other blood diseases.
"That's really one of the great success stories of stem- cell biology that gives us all hope," says Dr. David Scadden of Harvard, who notes stem cells are also used to grow skin grafts. "If we can re-create that success in other tissues, what can we possibly imagine for other people?"
Some of the new approaches, like the long-proven treatments, are based on the idea that stem cells can turn into other cells.
Einhorn said the ankle-repair technique, for example, apparently works because of cells that turn into bone and blood vessels. But for other uses, scientists say they're harnessing the apparent abilities of adult stem cells to stimulate tissue repair or to suppress the immune system.
"That gives adult stem cells really a very interesting and potent quality that embryonic stem cells don't have," says Rocky Tuan of the University of Pittsburgh.
One major focus of adult- stem-cell work for about a decade has been the ailing heart. In treating heart attack, for example, studies show stem-cell injections help the heart pump blood a bit better, said Dr. Warren Sherman of Columbia University.
Another heart-related condition under study is critical- limb ischemia, where blood flow to the leg is so restricted by artery blockage that it causes pain and may require amputation. The goal here is to encourage growth of new blood vessels by injecting stem cells into the leg.
One success is Rodney Schoenhardt of Metairie, La.
Schoenhardt had already had surgery on both legs for the disease, and his surgeon was talking about amputating his left leg. For research by Dr. Gabriel Lasala of TCA Cellular Therapy, Schoenhardt got 40 shots in each leg about 18 months ago, with stem cells going into his left calf and a placebo dose into the other. Soon, he said, the pain in his left leg was gone.
Schoenhardt, 58, now mows his lawn, and he remodeled his living room to fix damage from Hurricane Katrina.
"My wheelchair is in my garage, collecting dust," he said. "I'm even thinking about taking up a little tennis again."
Among the other diseases being studied for stem-cell treatments:
• Multiple sclerosis. In MS, the body's immune system repeatedly assaults brain and spinal-cord tissues, which can cause numbness in the limbs, paralysis or vision loss.
Last year, Dr. Richard Burt of Northwestern reported a small trial in patients with early MS that was aimed at rebooting the immune system to stop the attacks. He removed stem cells from the patients' blood, destroyed their immune systems and then reinjected them with their own cells to build a new immune system.
To his surprise, most patients improved. He's now conducting another trial to provide firmer evidence of improvement.
• Type 1 diabetes. It's also caused by a misguided attack by the immune system, this time on insulin-producing cells. Burt and colleagues reported last year that the "rebooting" strategy allowed some patients to go without insulin for four years.
• Cancers such as melanoma and kidney cancer. The idea is to transplant cells to produce a new immune system that will attack the diseases. Earlier work around a decade ago failed to give lasting benefit, but new approaches aim for better results, said Dr. Michael Bishop of the National Cancer Institute.