You may have recently heard about Tiger Woods and other athletes getting “PRP” therapy. What is PRP? PRP stands for “Platelet Rich Plasma” and it’s purpose is making the conditions in a damaged area more conducive to healing or “anabolic”. Here the term “anabolic” means making an area pro-repair or better able to heal.
Creating an anabolic healing environment is not a new concept in medicine and surgery. For centuries, physicians have known that some people have better innate abilities to heal, while others have less healing capabilities. The acronym “PPP” (piss poor protoplasm) was used in my residency training to mean a patient that due to disease or extreme old age was unable to heal after surgery. While we physicians have always known that some patients could have a compromised ability to heal, we haven’t paid as much attention to getting healthy patients to heal better. About 20 years ago that started to change in the dental community. Some dentists began experimenting with a simple concoction called “PRP” or “Platelet Rich Plasma”. The dentists used this stuff made from the patient’s own blood to help their dental implants heal.
PRP can be made in a bedside centrifuge form an intravenous blood draw. The blood is spun down with a disposable kit in such a way as to spin off the blood and plasma components into a waste container and spine down and concentrate the platelet fraction. Most PRP preparations are 3-5 times as concentrated as the normal blood platelet concentration.
PRP is a simple example of how we can improve the healing environment. The platelets contain growth factors that help to ramp up healing. These include TGF-beta, b-FGF, PDGF-bb, VEGF, IGF, just to name a few. Growth factor concentrations vary widely between patients as determined by Frechette and Martineau. Growth factors are like espresso shots for cells. A cell works at a certain pace to do its job. If we add growth factors (like those in PRP), it’s like buying all of the repair cells a bunch of Starbucks gift cards. The cells react to the growth factors like people react to triple espresso shots, they work harder and faster. So if we use an example of a construction site, where we have a few brick layers building a new wall, if we add growth factors, our brick layers will build our wall faster.
Does PRP work? That’s a good question. In this link is the latest published data. When used in tendon treatments (Achilles tendonitis, lateral epicondylitis), some studies show efficacy and others do not. Like most things in medicine, the jury is still out.
Is PRP stem cell therapy? No, PRP is the injection or addition of blood platelets for growth factor delivery, not stem cell therapy. In our clinic, we also use next generation level II tools beyond PRP. These include platelet lysate or PL. In the case of PL, our advanced cell biology lab makes PRP from the patient’s blood and then breaks open the platelets to make all of the growth factors immediately available. The big advantage to using PL instead of PRP is that PRP has to be mixed up each time we want to use it, but PL can be mixed up in a larger batch and stored indefinitely in a sophisticated freezing process known as “cryo-storage”. We also use various activated, incubated platelet supernatants or next generation PRP. Think of these as PRP 2.0. To make these next generation solutions, our lab starts with PRP, activates it with various natural substances, and incubates the platelets for several hours to several days. During this time the platelets are directed to produce certain natural growth factors that are important in specific types of healing. We then take that soup of natural, growth factors and use that instead of PRP. So for example, we can inject a solution that is rich in the joint and cartilage repair growth factor TGF-beta by telling the patient’s platelets to produce more of that natural growth factor.
In summary PRP is a natural growth factor cocktail that may help patients heal. In orthopedics it’s routinely used to help surgeries heal, aid in healing non-union fractures, and is injected for various types of tendon injuries. In cosmetics, it’s now being used in early human work to help with fat grafts and help skin rejuvenate. While it’s not stem cell therapy, it does appear to be an important part of very basic regenerative medicine and will likely take on a bigger therapeutic role in the future.