Twenty years ago, Dr. Alan Tyndall, a rheumatologist at University Hospital in Basel, Switzerland, was faced with giving a 37-year-old mother a grim diagnosis.
Scleroderma, the autoimmune disease that pumps excess collagen into the body, was turning her pulmonary arteries into stone.
The disease would be fatal. Even a lung transplant couldn’t save her.
So Tyndall and his colleagues, including hematologist Dr. Alois Gratwohl, came up with a bold plan.
They reasoned that since the root of the problem was malfunctioning immune cells, maybe those cells should be annihilated.
In other words, they decided to purposely destroy the woman’s immune system.
Of course, they couldn’t take down the offending immune system and leave her with no defenses against future infections. They would have to rebuild it from the ground up.
Enter the Stem Cells
That’s where the woman’s blood-forming, or hematopoietic, stem cells came in.
These cells are found in bone marrow and produce billions of new blood cells every day, including the white blood cells that fight infection.
The doctors administered drugs that coaxed these cells out of the marrow and into her bloodstream, where they could then be harvested and stored outside her body.
After four days of chemotherapy, they reintroduced these cells back into the woman’s blood, “like the engineers coming in after a bombing raid on a city,” Tyndall told Healthline.
The concept is identical to bone marrow transplants for leukemia and other blood cancers, Tyndall said. In fact, he and his colleagues were inspired by reports that such transplants performed for cancers were also clearing up autoimmune disorders in patients with both diseases.
Their bold move paid off. The woman’s scleroderma was not only halted, its course was somewhat reversed.
Treatment for Other Diseases
Since then, versions of this therapy, often referred to as hematopoietic stem cell transplant (HSCT), have been tested in patients with multiple sclerosis (MS), lupus, rheumatoid arthritis (RA), and other autoimmune diseases.
Despite the name, “the stem cells are not the therapeutic agent,” Tyndall said. Instead, they help the body rebound from the intense treatment.
Last year, the results of a preliminary HSCT trial of 151 MS patients showed that the therapy actually reversed the disability in about half the study group.
Those results are promising, but researchers don’t know why the treatment works in some patients and not in others.
In a 2011 review of European patients who had received HSCT for autoimmune diseases in the preceding 15 years, Tyndall found that about two-thirds did not respond to treatment, or responded and then relapsed.
The best candidate for this potentially toxic treatment is a patient with a poor prognosis whose organs are not yet too badly damaged, Tyndall said. According to the Multiple Sclerosis Society, younger people who have received fewer treatments tend to fare better in HSCT trials.
Risk vs. Reward
There are serious risks to this treatment, including infection and the development of secondary autoimmune disease.
Treatment-related mortality has been as high as 20 percent in some trials, although that risk is becoming less common as researchers become savvier about which patients to enroll in trials.
The acute risk has to be weighed against the long-term risks of the disease itself, which, Tyndall writes in his review article, is hard to do without lots of data from many randomized trials, which are not available yet.
The scarcity of data tempers the scientific community’s excitement about HSCT.
“It’s something that has to be done in the clinic under clinical trials to really demonstrate if that’s something that’s going to work for a large population,” Kent Fitzgerald of the California Institute for Regenerative Medicine, told Healthline.
Looking Toward the Future
Like a lot of potential stem cell therapies, HSCT hypothetically shows great potential in the future.
Twenty years after Tyndall’s treatment of the woman with scleroderma, HSCT remains a relatively radical treatment and is not available outside of preliminary studies.
Since it is a treatment different from traditional drug development, Fitzgerald said, safety-screening paradigms would have to be developed from scratch.
Still, he said, it’s a line of research that the community believes in.
“The most exciting aspect is that for the first time true eradication of autoimmunity has been achieved in some patients,” followed by healing of some damaged tissues, Tyndall said.
He also noted that the young woman facing death from scleroderma is still doing well and living a “near normal life.”