Nice piece this morning on PRP in the NYT. PRP means platelet rich plasma. Platelets are smaller than red blood cells and involved in clotting our blood and helping to heal injuries. Our blood platelets house a significant mix of growth factors including PDGF, IGF, FGF, TGF-beta, and VEGF. These growth factors, when concentrated in a bedside centrifuge to make PRP, can help assist healing. One of our close colleagues, Dave Karli of Steadman-Hawkins in Vail uses PRP extensively. It’s a great next generation play to treat tendinitis and things that need a little help in healing. As a result, athletes have used PRP to get back to the field faster. I would call PRP Regenerative medicine 2.0. This category of tools allow doctors to concentrate various blood products (PRP in the case of blood and BMAC in the case of a marrow aspirtae).
What about the next step in regenerative medicine? Regen Med 3.0? While the 2.0 applications like PRP and BMAC allow for growth factors or very very dilute stem cell mixes, what about placing many more building blocks at the construction site? What if you could also deliver a stone mason and general contractor to assemble the bricks into new tissue? Based on the stem cell literature to date, to do that for non-healing orthopedic problems, you would have to deliver concentrated MSC’s. MSC’s can serve as building blocks in that they can differentiate into new tissue. They also serve as the mason and general contractor in that they can coordinate the repair response, bringing in new blood vessels and modulating the healing inflammatory response. So while the 2.0 techniques are great to kick start healing where it might already want to happen, the 3.0 techniques of delivering many more stem cells to the “construction site” will be needed when healing is unlikely to occur. The 3.0 techniques can be performed safely and efficiently with minimally manipulated culture expansion techniques.
What about Reg Med 4.0? We’re hearing about this research now. Headlines like reprogrammed skin cells, curing HIV with donor CD34+ stem cells, and off the shelf stem cell products are all examples. This involves more than minimal manipulation for short culture periods, such as inserting new genes or exposing cells to exotic growth factor cocktails to bring new properties to bear. I would also include in this category the use of “off the shelf” donor stem cell products that are grown in bio-reactors, due to their risk of transfering new genes into the host. While these plays are likely more powerful than Regen Med 3.0, they also carry more risk to the patient, so longer term safety data and tight regulation are required. Expect these treatments to be available and covered by insurers in the next 5-10 years.
Regen Med 5.0? Who knows…