With a new mouse study out Thursday suggesting that stem cells could be a treatment for multiple sclerosis, many neurologists are likely to face more questions from patients about stem cell therapies.
For now, the answer will probably be, please try to be patient.
In the new study, researchers led by Jeanne Loring, PhD, of the Scripps Institute in La Jolla, Calif., and Thomas Lane, PhD, of the University of Utah (where he recently relocated from the University of California Irvine), found that infusion of human neural precursor cells partially restored walking ability in mice with a virally-induced demyelinating condition resembling MS.
The neural precursors, which were derived from a human embryonic stem cell line, also appeared to induce remyelination of damaged nerve fibers, the researchers reported in Stem Cell Reports.
But in addition to the obvious caveats about animal studies, this one may bear extra caution because of the unusual model.
Most animal research on MS involves experimental autoimmune encephalomyelitis or EAE, which is induced by injecting mice with myelin basic peptide to provoke an anti-myelin immune attack. It more closely resembles the human disease than most animal models of other conditions.
The study by Loring, Lane, and colleagues did not use EAE, however. Instead, they induced a demyelinating neuroinflammatory condition by injecting the animals intracranially with a mouse hepatitis virus (MHV). Although the demyelination is similar to that seen in human MS, and the subsequent clinical manifestations are likewise similar, the viral cause may or may not be related to that of MS.
Some experts, of course, believe that MS has a viral origin, but many more do not. The neuroinflammation seen in the MHV model is not necessarily identical to that of MS, and therefore it's not clear that the neural precursor cells will have the same effect in MS patients, or even in EAE mice.
Still, Jeffrey Cohen, MD, who heads the experimental therapeutics section at the Cleveland Clinic's Mellen Center for Multiple Sclerosis, told us that "encouraging results have been seen with several types of stem cells in animal studies," and that human studies were already underway.
Two such trials were the subject of preliminary presentations at the recent American Academy of Neurology annual meeting.
Both involve autologous mesenchymal stem cells (MSCs). One of the studies, led by Saud Sadiq, MD, of the Tisch Multiple Sclerosis Research Center in New York City, is using neural progenitors derived from MSCs to be injected intrathecally. A phase I trial launched earlier this year, with a projected enrollment of 20 and October 2016 as the estimated completion date.
The other study involves intravenous administration of autologous MSCs and is being conducted in Great Britain by researchers at Imperial College London. Designated as a phase II trial with a placebo-controlled crossover design, it is enrolling 15 patients with some results expected next year.
At AAN, investigators mainly talked about the trial designs along with some early safety data, which were good. It's too early for efficacy results.
However, these studies may be eclipsed by stem cell "therapies" already being sold to desperate patients, which -- as Cohen discussed in this video interview were conducted last month -- have mainstream neurologists concerned.
One such patient was the subject of a Colorado television news report. According to station KREX in Grand Junction, Colo., a local woman named Pam Claypoole was planning to travel to Panama's Stem Cell Institute for a second treatment -- and was hoping to raise $20,000 to pay for it.
The institute uses allogeneic MSCs isolated from donated umbilical cords. Surprisingly, perhaps, it makes relatively modest claims for the treatment.
"Mesenchymal stem cells have immune regulatory properties which may stop the immune system from attacking the myelin sheath," according to the institute web site.
"Mesenchymal stem cells may also potentially help remyelination (regeneration of the myelin sheath) of the affected neurons," it adds.
The institute is taking its show on the road to New York City this weekend, sponsoring a "spring seminar" at a midtown hotel that will promote stem cell therapies for autism, spinal cord injury, MS, lupus, and rheumatoid arthritis.
And stem cell treatments can be had at facilities like StemGenex in La Jolla, Calif., which offers therapies for a range of conditions including Alzheimer's disease, diabetic complications, and chronic obstructive pulmonary disease as well as MS.
No, wait -- we take that back. The StemGenex website includes a page titled "FDA" that states, "StemGenex is not offering stem cell therapy as a cure for any condition, disease, or injury. No statements or implied treatments on this website have been evaluated or approved by the FDA. This website contains no medical advice."
It also characterizes its work with patients as "studies."
But, patients have to pay for their treatments. The website is vague on how much, but it does stipulate that patients must put down $2,500 just to schedule a procedure. There's certainly no hint that participants in these "studies" might receive a non-stem cell control treatment.
And ClinicalTrials.gov has no listings for any trials sponsored by StemGenex or with its chief scientist, Jeremiah McDole, PhD, as principal investigator. Any study intended to support an FDA submission has to be registered there.
So this does not have the appearance of high-grade scientific research. But we can't call it a flimflam either, since it's highly probable that patients receive exactly what they want -- a shot of hope.
Striking a Nerve is a blog by John Gever for readers interested in neurology and psychiatry.