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Benefits of "stem cell" and PRP Injections

by: Richard Santore, MD

February 21, 2020

The concept of getting a ‘stem cell injection’ that will stimulate regeneration of normal cartilage in a painful, arthritic hip or knee joint is a compellingly attractive concept. It is so attractive, in fact, that individuals are traveling to other continents to obtain these injections at a cost of $8,000 US Dollars, or more, per injection as well as to many such centers in the U.S. Many thousands more are spent on travel and other related expenses. It is important to understand the difference between hype that preys upon the understandable aspirations of these individuals and the reality of what validated science has to offer in the year 2020. Fact: There is no FDA approved stem cell injection in the United States today. Period. The FDA is doing its job to protect the public safety and will hopefully soon come down hard on those who are providing “stem cell injections” in the United States under false pretenses. Fact: in an analysis of millions of cells from human bone marrow aspirates not one true stem cell can be identified. This holds true for injections derived from fat tissues or blood or any other source in the adult human.

There are certain tissues in the human body that regenerate on a regular basis, such as intestinal lining cells, skin cells and red and white blood cells. The regeneration does not come from stem cells but by molecular signaling that turns on progenitor cells that are already programmed for that particular type of cell. True stem cells, or pluripotent cells which are capable of turning into any type of cell type, only exist in the embryo, and only in the first few days after fertilization. Current research on embryonic stem cells in the US is only permitted on donated eggs from in vitro fertilization when the eggs are no longer needed. Suffice it to say that there are enormous ethical and religious aspects to this area of research and no cell therapies from this source are in use in humans in the U.S.  After differentiation into muscle or skin cells, those cells cannot turn into something else.

One of the pioneers of serious stem cell research, Dr. Arthur Caplan of Case Western Reserve University in Ohio, first described mature cell lines which he named Mesenchymal Stem Cells, later revised to Mesenchymal Stromal Cells and most recently to Medicinal Signaling Cells. He strongly advocates against referring to injections of cells as ‘stem cell injections”. That term not only is inaccurate and misleading but also violates FDA advisory statement guidelines. The proper way, at this point in time, to describe cells harvested from bone marrow,  fat, etc., for the purpose of stimulating some type of regeneration, is to call them Medicinal Signaling Cells.

Understanding the molecular signals that stimulate a dormant progenitor cell to ‘turn itself on’ to produce a mature cell of its particular type is one of the most intense areas of interest in research today. It has nothing to do with injecting true stem cells, which do not even exist in such tissue harvests, but has everything to do with stimulating new cell formation.

At the JP Morgan Healthcare Conference in January of 2020, I attended a presentation by a company from the Boston area involving exciting early clinical research on this very topic. I also met with the president and the chief scientific officer of the company. Their scientists discovered a molecular signal that intestinal cells use to turn on the regular regeneration process. They developed a way to produce this molecule and injected it into the cochlea of properly enrolled human subjects with hearing impairment and all six subjects experienced improved hearing, some dramatically. The molecular signal caused regeneration of hair cells inside the cochlea. This was heretofore believed to be impossible. It should be emphatically stated that this was done with full FDA approval as a high risk, experimental study with all volunteers fully informed of the risks as well as possible benefits. No one can go to these scientists and ‘pay cash’ for a similar injection. The FDA has approved another research project for this company to test the use of molecular triggers to regenerate the nerves in patients with Multiple Sclerosis. In fact, it will be years before the validation of efficacy and safety of this type of therapy is established.

If there is any benefit from the so-called stem cell injections that are being given today it is likely derived from yet to be discovered molecules and, or, an anti-inflammatory effect. My advice is to stay far away from anyone who advertises for stem cell injections and who may not even understand that there are no stem cells in the ‘potion’ that is being administered. Patients have died or been seriously injured from these injections or from complications at the harvest sites.

What about PRP injections? PRP refers to Platelet Rich Plasma. Platelets are the small particles in the blood that coalesce around bleeding sites to initiate purposeful blood clots to stop hemorrhage. The injectable fluid is created by drawing off some blood and concentrating the platelets by spinning in a centrifuge. Cells of different types organize at different levels in the tube. The desired substances are then transferred to a syringe and can be injected into tendons or joints. The concentration of white blood cells can be controlled and there are specific indications for ‘leukocyte (white cells) poor’ or ‘leukocyte rich’ versions of PRP. Though initially thought to have some regenerative capacity, the benefit from these injections likely accrues from anti-inflammatory effects of some of the molecules. PRP has been shown effective in the treatment of elbow tendonitis and has been shown to be at least equivalent to steroid injections in the arthritic knee. However, the costs are not covered by any insurance plan or Medicare and the injections are costly, running from $500 to $800 or more per injection. Remember, there are no stem cells in PRP either.

The take home message here is that the FDA is closely watching the currently unregulated market of “stem cell injection centers” which purport to ‘cure’ everything from paralysis to diabetes to advanced arthritis to multiple sclerosis. Hopefully the agency will come down hard on the owners and practitioners of these ‘centers’ in fulfillment of the FDA’s mission to protect the safety of the American public. Honorable physicians and surgeons will applaud this when it occurs, likely sometime in the latter part of 2020.  There is understandable frustration with the years it takes to get a promising new drug or therapy approved by the FDA. However, we should actually be thankful for the work that they do. The dedicated employees of the FDA make much less income than if they worked for big pharma.

On the day of publication of this essay, I did a Google search of “stem cell injections”.  There were 389,000,000 hits in 0.97 seconds. That says it all about the intensity of the interest of the general public in this area. I hope this information will be helpful to anyone who reads it and who is considering one of these injections.

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