Our bodies have abundant stem cells, but in adulthood they have become dormant. Arguably the most studied and certainly the best known Biologic/Regenerative modality in veterinary medicine involves the use of “Adipose-derived Autologous Mesenchymal Stem Cell” transplantation. It is important to note here that we are not talking about embryonic stem cells! “Autologous” means that the stem cells are the dormant ones isolated from the patient (from fat, “adipose” tissue) that are then subsequently placed (“transplanted”) back into the same patient. The principle of this therapy is to concentrate stem cells and growth factors, activate them, and get them to damaged tissue to elicit a cascade of anti-inflammatory and healing processes. The advantages of this technology is that there is published literature supporting its use in osteoarthritis (dogs) and ligament injuries (horses), and can be administered intravenously in addition to local infiltration e.g. joints. Further, the stem cells can be frozen and even cultured so that theoretically, there remains available a supply of viable cells for repeating the transplantation far into the future. In fact, a new application offered is the opportunity to collect fat at the time of any other surgical procedure (for example, spay/neuter), then culture those cells for an indefinite supply and perpetual use at any point in life – even years later!
Platelet Rich Plasma or “PRP”
Platelets are normally known for their function of clotting blood, but recent research has revealed they also have hundreds of unique proteins and growth factors that have been shown to help manage inflammation and tissue degeneration. Because of its relative simplicity (isolated from a blood sample and injected into tissue), the ability of PRP to affect tissue healing and pain relief is an area of intense study. Dr. Epstein even has had PRP injections into his own arthritic shoulder joint!
Autologous Conditioned Serum
ACS involves drawing a patient’s blood sample, incubating it with special test tubes designed to active certain growth factors and anti-inflammatory mediators, then centrifuged to collect the now “conditioned” serum for injection into a joint or other tissue. There is one FDA-approved ACS product for horses, and similar products are being developed for dogs.
Bioscaffolding or Extracellular Matrix
This involves taking tissue from another animal (usually small intestine or bladder from a pig) and removing all of the “live” cellular material from it. What is left are strands of collagen and associated molecules. Studies have shown that when this material is injected into and around damaged tissue, it forms a scaffold for cell proliferation, differentiation and integration…and possibly activating the area’s existing stem cells. . You are probably familiar with this technology if you have heard about people that have been able to “grow back” damaged tissues and even growing “artificial tissue” (ears, bladders) in the laboratory. Its ability to treat the pain of osteoarthritis is just beginning to be explored, but anecdotal experience, and one pilot study, is encouraging. An advantage of this technology is that the material comes as a gel that can be stored until ready to use – no anesthesia or surgery to harvest tissue, no special equipment to process tissue or blood from the patient. When ready to implant, it is simply warmed to body temperature, pulled into a standard syringe, and then injected into the site and around areas of soft/hard tissue damage. Our hospital has been utilizing this modality since 2011 and consider it a viable option for many patients. A disadvantage, it must be said, is that there is very little if any scientific literature at this time to support clinical use.
Gene Therapy: The future of medicine
The “Holy Grail” of Biologic medicine is to learn how to instruct the body to click off certain DNA segments (genes) and click on others to teach the body to repair itself. While an area of intense research, it currently remains a hope of future therapy rather than anything we can apply clinically at this time.
Conclusion
As with all medical procedures, proper patient selection and evaluation prior to Regenerative Medicine procedures is extremely important. The doctor needs to set appropriate patient and pet parent expectations for any therapy option. This usually includes radiographs of affected sites, blood tests and urine tests for internal health – especially in older patients we are treating, that often will have other pre-existing conditions.
One KEY FACT about Biologic/Regenerative Medicine: None of these therapies will “fix” the actual underlying cause of genetic or traumatic damage that occurred in a joint. We are looking to Biologic/Regenerative Medicine to help manage pain and improve comfort, mobility, and ability. Because the actual “biomechanics” of an abnormal joint will still be there, some patients will need a repeat therapy in months or years following. In the meantime, the expectation is to see clinical improvement after treatment at the same time we reduce other systemic medications being given.
This frontier is exciting and challenging at the same time, for pet owners AND veterinarians. It is always best to consult with a veterinarian whom has studied and utilized Biologic/Regenerative medicine options in their practice, and Dr. Epstein at TotalBond Veterinary Hospitals & Carolinas Animal Pain Management remains one of a handful of veterinarians in the country with this type of expertise and experience.