Are mesenchymal stem cell injections safe?
There are three main types of stem cell products: autologous (your own) stem cells, autologous expanded stem cells, and allogenic (taken from a different person) stem cell treatment. Autologous stem cells are typically obtained from your bone marrow or your fat through bone marrow aspiration and liposuction respectively. Allogenic stem cell products are typically purchased by physicians from a company that obtains them from multiple donors and processes them.
The safest, oldest, and most researched approach is the first one, autologous stem cell injections. That is in part due to regulation and in part due to the fact that this approach involves the least amount of manipulation of the stem cells. This means fewer opportunities for contamination with bacteria or viruses and a smaller likelihood of unexpected complications such as the development of new cancer at the site of the injection.
Both Health Canada approved studies use this approach.
The next type of stem cell product is autologous expanded stem cell treatments. This treatment involves removing stem cells from your fat or bone marrow, culturing them in a petri dish for days or weeks in order to allow these cells to multiply, and then injecting them back into your damaged organs or infusing them into your vein in hopes of stimulating healing. The advantage of this method is that many more stem cells are produced compared to standard stem cell injections. The disadvantage is that the culture dish is a very unnatural environment and the stem cells change and literally become old (senescent) while they divide in culture. So these stem cells are no longer identical to your original stem cells and therefore how they will behave in your body is harder to predict. Also, while these cells are outside of your body there is a significant risk of contamination with viruses or bacteria from lab technicians’ hands and even from the air. So higher risk of infection. In terms of effectiveness, expanded stem cell treatments have not been proven to be superior to standard stem cell procedures, however, this is a young field and research is still ongoing.
The final stem cell therapy is allogenic where stem cells are derived from a donor. These are often the least differentiated stem cells often derived from amniotic fluid or umbilical cord. There have been questions about whether amniotic fluid-containing products actually have any live stem cells[1].
On the other hand, umbilical cord structures such as Wharton Jelly contain a lot of stem cells and these stem cells resemble embryonic (less mature) stem cells far more than adult stem cells derived from fat or bone marrow. The advantage of this product is the ability to provide younger stem cells in greater quantities. The risks include relying on the company collecting and packaging the product to screen for hepatitis and HIV and other bacteria and viruses. Also, as this product contains immature cells, the risks of cancer could be potentially higher. In terms of effectiveness, it has not been proven to be more effective than other stem cell treatments at this time. These products are not available in Canada as they are not Health Canada approved.
Source:
Panero, A. J., Hirahara, A. M., Andersen, W. J., Rothenberg, J., & Fierro, F. (2019). Are Amniotic Fluid Products Stem Cell Therapies? A Study of Amniotic Fluid Preparations for Mesenchymal Stem Cells With Bone Marrow Comparison.The American journal of sports medicine,47(5), 1230–1235.