Multiple sclerosis is a devastating disease that has no cure. So when something comes along that offers hope, it garners worldwide attention. That’s the case with stem cell therapy for MS. But it’s far too early to assume it’s a cure. “There’s a lot of promise, but it’s not ready for prime time. The science is still very much in its infancy,” says Dr. Jeffrey Cohen, a neurologist, researcher and director of experimental therapeutics at Cleveland Clinic’s Mellen Center for Multiple Sclerosis Treatment and Research.
Understanding MS Damage
In MS, the body mistakenly unleashes an inflammatory attack on the central nervous system. The immune system sends cells (such as T cells, B cells and macrophages) to attack or chew up myelin (the protective covering that safeguards nerves), nerve fibers and brain cells.
In most cases of MS (relapsing-remitting MS), the damage comes in waves of attacks, separated by periods of remission, during which the body tries to make repairs. In progressive MS, the damage never stops, giving the body little chance to make repairs.
The resulting scar tissue or damage then interrupts nerve signals throughout the body, leading to problems with strength, coordination, vision and cognition, and causing any number of potential symptoms or co-existing conditions such as depression, fatigue, bowel and bladder issues, and pain and disability.
Stem Cell Therapy
Stem cells can become any kind of cell in the body. They help us grow when we’re in the womb, and they play a role in the body’s repair functions after we’re born. Stem cell therapy aims to harness this power.
Several different types of stem cells and approaches are being studied to treat MS. Cells may come from donated human embryos or from a person’s own bone marrow, fat or skin. Delivery methods include injection into the brain, spinal fluid or blood.
The various approaches in MS stem cell therapy boil down to two main goals:
- One goal is to use stem cells as part of a strategy to stop MS inflammation. The malfunctioning immune system is wiped out with chemotherapy and then “rebooted” with haematopoietic (blood-cell producing) stem cells. This is an approach used to treat some types of cancer, such as leukemia or lymphoma. In MS, a person’s own haematopoietic stem cells are collected prior to chemotherapy, then reinfused afterward.
- The other goal is to use stem cells to promote the repair of MS damage that’s already occurred, including reforming myelin. Scientists isolate the cells from a patient, grow them in a lab and then reinfuse them into the patient.
Does It Work?
We don’t yet know if stem cell therapy is a solution for MS. At this point, many of the studies are only at the point of evaluating whether a particular type of stem cell therapy or means of delivery appears safe.
But there is encouraging evidence that stem cell therapy may one day play a role in treating MS. For example:
- A clinical trial published in February 2017 suggested that suppressing the immune system aggressively (immunosuppression) and then getting a transplant of haematopoietic stem cells was associated with a pause in MS disease activity and forestalled the worsening of MS symptoms for up to five years, especially among younger people with relapsing-remitting MS.
- Another clinical trial of people with highly active relapsing MS, also published in February 2017, suggested that two-thirds of patients who received immunosuppression and then haematopoietic stem cells had no relapses for five years, and no new MRI lesions or progression of MS.
- A 2016 study in mice suggested an association between injections of human mesenchymal stem cells (which appear to support the repair process) and a reduction in MS-like damage to the brain and spinal cord tissues.
Not So Fast
While stem cell therapy offers hope and some approaches appear safe, the practice of using stem cells to treat MS is not yet proven safe or successful. For example:
- Stem cells are capable of developing into any cell – including cancer cells. “Stem cells have some characteristics similar to cancer cells, so the concern is that they may convert to cancer, especially in a disease like MS in which the immune system already is malfunctioning,” Cohen explains.
- Stem cells have the ability to develop into any kind of tissue. “When you administer stem cells that might go to brain, they may form the wrong tissue there, such as bone,” Cohen says.
- Transferring stem cells to a patient has the risk for infection. “Cells can become contaminated when they’re grown in a lab. And there’s a risk for infection when you remove cells or inject them back in, just like there’s a chance for infection with surgery,” Cohen says.
- It’s unclear if stem cells know exactly where to go in the body.
- It’s unclear which source of stem cells is most effective. “Should we get them from bone marrow or fat, from the patient or from someone else who doesn’t have MS?” Cohen asks.
- We don’t know for sure if stem cells are an appropriate treatment for regenerating myelin. “It appears a lot of patients repair their myelin through pathways that exist already but don’t function normally. So maybe the problem is that they don’t produce enough myelin. If that’s the case, putting more cells into the brain isn’t going to fix the problem. We have to figure out why that is,” says Dr. Peter Calabresi, a professor of neurology and director of the MS Center at Johns Hopkins University School of Medicine.
What You Should Do
Stem cell therapy for MS is not yet approved by the U.S. Food and Drug Administration. That doesn’t mean it’s not available.
Clinics around the globe offer procedures claiming to be stem cell therapy. This “stem cell tourism” is available to people willing to pay for treatment out of pocket. “Those clinics were in other countries at first, like Costa Rica or Mexico, but now those are springing up in the U.S.,” Cohen says. “They’re charging $10,000 to $20,000 for treatment,” Cohen says.
“The clinics make claims, but there’s no substantiation or detail about what’s being given. The source of the stem cell is important. But you don’t know what you’re getting,” Calabresi adds.
Both doctors have had patients who’ve gone to stem cell tourism clinics and come home with no change in MS, and even some complications, such as a spinal cord tumor. Both doctors urge people to avoid the clinics.
But what if you’re tempted to try one? “Be skeptical that you’re being provided the therapy that’s being claimed. Get details about the therapy. And make sure there’s a plan in place with your own doctor for addressing complications when you get home,” Cohen says.
For now, doctors say the cautious approach is taking part only in a clinical stem cell trial at a research facility, or waiting until science has given us more answers. “It definitely has a place in research,” Cohen says, “but stem cell therapy is not ready for routine medical use at this point.”