I got an e-mail yesterday from a physician colleague asking about whether IV stem cell therapy for knee arthritis was for real. It hit me that this would be a great blog topic as the number of physicians offering IV stem cell therapy has exploded in recent years. So is this a good idea? Is there much science behind it? Or is this just more hype?
Way back when, before most physicians had heard of stem cell therapy, I was the founding president of an organization called ICMS (International Cellular Medicine Society). The organization was the first of its kind, and all of the newer physician organizations popping up in physician cell therapy owe their roots to ICMS.
Back in 2008, there was a hearty collection of physicians who were true pioneers in cell therapy and patient supporters (hat tip to Barb Hanson). There were all sorts of cell therapy regimes that were being used internationally, and one of them was adipose stem cell therapy delivered IV. Based on the physicians who were using this technique, it likely originated out of Asia. A Korean veterinarian turned cell-therapy entrepreneur was the first scientist who had shown some animal data, but he didn’t use the same-day fat stem cell procedure being used in the U.S. today; instead, he used culture-expanded mesenchymal stem cells from fat.
The initial idea behind IV stem cell therapy was twofold. First, early stem cell clinics had a very hard time finding specialists who knew how to place stem cells in specific parts of the body. On the other hand, physicians and staff who could start an IV were easy to find. Second, it was reasoned that stem cells injected IV would make their way to far-flung areas of the body, such as the joints, liver, brain, heart, etc…There was just one little problem—eventually, science stood in the way.
In 2009 an interesting paper was published that seemed to throw some cold water on the IV stem cell party. Researchers found that when injecting stem cells IV, almost all of them got trapped in the lungs in what they termed a “pulmonary first-pass effect.” In addition, almost none of the stem cells found their way to the brain. Given that many early patients who were receiving IV stem cell therapy at the time were being treated for neurological conditions, this seemed to be a big problem.
There was another problem as well, this one more obvious. Many of the tissues that were being treated with IV stem cells, like cartilage in joints, damaged hearts, or bad nerves, often had poor blood supply, which was one of the reasons they often failed to heal in the first place. Since the stem cells delivered IV were using the circulatory system to hitch a ride to the site of tissue damage, this was a real problem as well.
Despite these challenges, some patients who receive this therapy do report improvements. Why or how? This is likely from the trapped cells in the lungs either giving off helpful growth factors (paracrine effects) or the cells eventually making their way out of the lungs. In addition, some don’t get trapped and do circulate. So for patients with diseases that are stoked by whole-body inflammation, it’s possible that cells trapped in the pulmonary system may still act on the whole body to tune down that inflammation. In addition some cells may break free to roam and then may have local effects. Having said that, cells could likely work far more efficiently at the site of damage if the physician expertise is available to place them where they need to be.
Performing the search “stromal vascular fraction adipose intravenous” at the US National Library of Medicine this morning yields five papers. All of them are small-animal-model studies with no human data being found. Four of the five have nothing to do with a same-day stem cell therapies, and most involve using the very different culture-expanded stem cell technique. Only one rat study dealt with replicating a same-day fat stem cell procedure injected IV for a model of a heart attack. That study showed that these cells worked better when delivered about a week after the infarct.
So is there much research on this topic of IV stem cell therapy? No, very, very little.
One of the things that has always been a problem is IV stem cell safety. While a study that implants cells under imaging guidance in a specific spot that the cells are unlikely to leave can hang its hat on determining whether that spot has problems over time, IV stem cells could cause havoc anywhere. While most are trapped in the lungs, some do circulate throughout the body. As an example, if the physician is concerned about whether stem cells may cause cancer, a study looking at knee injections could focus its primary attention on whether the knee developed cancer and, secondarily, whether the patient had any evidence of the disease. However, in an IV stem cell safety study, any part of the body is a possible candidate for a tumor. Hence, these studies need to be much larger and better designed than the knee study.
This week, we identified a naturopath who was injecting amniotic fluid intravenously (IV) to treat knees despite the product labeling telling the doctor that there was DMSO (a cryoprotectant that isn’t safe to inject IV) in the vials. So already I was a little sensitized to the IV stem cell issue. Then I got this e-mail from a physician colleague:
I know the physician whom this doctor is referencing, and, yes, he does use bone marrow concentrate, injected IV, in a same-day stem cell procedure. When I first heard of this, I, too, was surprised as there is no evidence to support that this would help a patient’s arthritis, and the doctor is an orthopedic surgeon capable of performing simple joint injections. I again searched the US Library of Medicine this morning to see if there was any new research on the use of bone marrow concentrate injected IV, and there was none. So basically we have a practice that isn’t supported by even an animal model to show it would help a patient.
What gives? Why would this physician inject a patient with bone marrow stem cells IV? As far as I can tell, without any evidence that this would be helpful, the doctor has decided to replicate the business model of adipose stem cell clinics that replicated the business model of Asian clinics that were injecting fat-derived, culture-expanded stem cells.
The upshot? While IV stem cells may be here to stay, it’s a mystery to me why anyone would want to inject bone marrow concentrate into a patient’s veins without good evidence that this is safe and at least some animal models showing it helps common things, like arthritis. In the meantime, the IV stem cell therapy train keeps rolling, but without a lot of evidence that either same-day fat stem cells or bone marrow stem cells injected this way is helpful. At this time, we’ll avoid getting on that train as we have for the past 11 years.
About the Author
Christopher J. Centeno, M.D. is an international expert and specialist in regenerative medicine and the clinical use of mesenchymal stem cells in orthopedics. He is board certified in physical medicine as well as rehabilitation and in pain management through The American Board of Physical Medicine and Rehabilitation.…