Texas Gov. Rick Perry received an injection of his own stem cells during spinal fusion surgery last month and wants his state to be a leader in the use of adult stem cells in medical treatment.

But using a concentrated mixture of adult stem cells to fuse bone hasn't been tested in any major U.S. trials, raising questions of whether a governor (and reportedly a potential Republican presidential candidate) should be advocating an unproven medical procedure.

Perry and a state representative who has multiple sclerosis championed a healthcare bill that created an adult stem cell bank in Texas. A month after Perry signed that bill into law, his friend, Stanley Jones, MD, a Houston-based orthopedist, performed spinal fusion surgery on the governor using Perry's own stem cells to treat a recurring spinal injury, according to an article in the Texas Tribune.

The Tribune also said that Jones is a major advocate for adult stem cell therapy: Jones says he was cured of his debilitating arthritis after receiving injections of his own stem cells in Japan.

Experts contacted by ABC News/MedPage Today, who weren't familiar with the specifics of Perry's surgery, guessed that the governor had mesenchymal stem cells cultured from a biopsy of his own marrow or fat, that those cells were concentrated in a lab, and then were reinjected onto a scaffold-like device implanted in the spine.

Following the surgery, according to the Texas Tribune, Perry and Jones reportedly urged the Texas Medical Board to hold a meeting to explore ways to regulate the procedure in Texas.

The procedure is similar to spinal fusion surgery using a piece of bone harvested from the patient's own iliac crest to fuse two or more vertebrae. However, mesenchymal stem cells have a higher stem cell concentration than what is found in the iliac crest, and after the cells are spun in a centrifuge, the stem cells become even more concentrated.

Mesenchymal stem cells differ from iliac bone cells because they are multipotent, meaning they can turn into bone, fat, cartilage, muscle, and skin.

There have not been any phase III clinical trials that tested the utility and safety of stem cell spinal fusion procedures, nor have there been any published trials of the procedure in the U.S.

A Chinese study randomized 56 patients with degenerative disc disorder, lumbar instability, or spinal stenosis to receive either their own iliac crest bone, or enriched mesenchymal stem cells from bone marrow. The mesenchymal stem cells were enriched and spun, which researchers found greatly increased the concentration of stem cells. They concluded the enriched mesenchymal stem cells are "a good bone substitute in posterior spinal fusion."

Nick Shamie, MD, president of the American College of Spine Surgery and an associate professor at UCLA, said he used a similar method in patients and has had "numerous" examples of success. In one case, Shamie treated a young woman who was suffering from painful vertebra slippage for 12 years. He used her own stem cells to fuse her spine, and two-and-a-half months after surgery she is pain-free, he told MedPage Today.

However, there is some concern about what happens to cells when they are concentrated.

Bryon Petersen, PhD, a stem cell researcher at Wake Forest Baptist Medical Center, in Winston-Salem, N.C., said that culturing cells in a lab for a long period of time could potentially have a "deleterious" effect on the cells and transform them into potentially cancer-causing cells. Those cells must be carefully weeded out before being injected into a patient, he said in an email to MedPage Today and ABC News.

However, he added that the idea of using one's own stem cells to cure an ailment -- "self healing self" as he phrased it -- is a "very real possibility" and a "technology that the United States should actively be pursuing."

While Shamie and Peterson expressed excitement about stem cell spinal fusion, other experts contacted by ABC News/MedPage Today said the procedure is untested and not ready to be marketed to the American public.

George Daley, MD, PhD, a professor of biological chemistry and molecular pharmacology at Harvard Medical School, pointed to the dearth of evidence on the value of injecting mesenchymal stem cells, and said he worries that the procedure is being done based on anecdotes or observational trials.

"I suspect that what is going on here is part of the world-wide rush to commercialize stem cells prematurely, to capitalize on the hype and [make] a buck, long before the treatments have been proven safe and effective," Daley said in an email.

Richard Fessler, MD, professor of neurological surgery at Northwestern University's Feinberg School of Medicine, echoed Daley's sentiments.

"Although this is a promising technology for the future, at this point there is minimal evidence that it is effective in humans," he said in an email.

Jonathan Moreno, PhD, professor of biomedical ethics at the University of Pennsylvania, was harsher in his assessment:

"The medical claims being made for this 'treatment' are nonsense," he said, also in an email.

Moreno dismissed the science of the procedure, but said the political ramifications of the Perry situation are especially interesting: "Namely, how talk of a stem cell industry in Texas would cause anxiety among cultural conservatives that such an effort could involve more controversial forms of research, like embryonic stem cells," he said.

Adult stem cells are not the same as embryonic stem cells. Perry -- and many conservatives -- oppose using cells from human embryos for research.

Daley pointed to another political issue: A governor using his power to promote a procedure that hasn't been proven.

"It's sad when someone in such a powerful position like the governor of a major state can act without the benefit of evidence-based medicine," he said.

Still, others like Peterson are waiting to see how the new technology evolves.

"It will be interesting to see just what happens in this case and hopefully many more cases to come," he said.

This article was developed in collaboration with ABC News.