A new stem cell lab opened May 18 at the UC Davis veterinary school, providing revolutionary improvements in treating horses with extensive injuries, including bone fractures and damage to ligaments, tendons and joints.
The lab, which serves solely as a treatment facility, injects healthy stem cells into the damaged tissue of an injured horse, thereby healing even the most traumatic of injuries.
“Right now we’re offering this type of therapy often in our most severe or chronic lesions, where there really wasn’t any other hope,” said Dori Borjesson, veterinary clinical pathologist and faculty member working in the regenerative medicine lab. “Horses would often have to retire from racing, but we’re seeing animals go back and return to health and fitness that basically would not be expected to do so before this lab opened.”
Normally, when an animal has a lesion due to traumatic injury, new cells form and replace the damaged tissue. However, scar tissue formation also occurs as part of this healing process, and scar tissue is not as strong as the tissue had been before the injury. Injection of stem cells into the site of injury bypasses this process, allowing the damaged cells to heal such that all of the new cells that are grown are no less strong than they had been.
“With stem cells you can repair a tendon with tendon cells, not scar tissue,” said Sean Owens, veterinary clinical pathologist and faculty member. “Stem cells would be able to go in there and grow into normal tendon tissue, as opposed to forming a scar, which is inherently weaker than the tendon cells.“
This type of treatment exemplifies regenerative medicine, Borjesson said.
“The potential for cells to regenerate the cells to their original tissue as opposed to forming a scar … and help organ structures recreate themselves as they once were,” she said.
The veterinarians stressed that embryonic stem cell usage – a highly controversial area of biomedical research and treatment – is not employed at this laboratory. Instead, undifferentiated blood cells – mesenchymal cells and hematopoietic cells – are taken from the bone marrow of a healthy horse and are injected into the site of lesion of the injured horse.
Bone marrow-based stem cell transfer confers a great advantage: Because these cells are not mature, the immune system of the patient that receives the stem cells does not reject the cells, as is often seen in organ transplants.
“One of the great things about these cells is that you don’t have to [put the horse] on immunosuppressant drugs, which can lead to other complications,” Borjesson said. “That is the potential wonder of these cells.“
But the use of stem cells to treat injuries is not equine-specific. There are prospects that these same types of cells in small animals and humans can treat their lesions, too.
“Stem cell use lends itself to humans, dogs and cats,” Owens said. “One of the things that is very beneficial is that our success directly influences the success of human researchers. If we can heal tendons or ligaments in a horse, researchers will be able to directly use what we have discovered and heal ligaments in humans. The work we do is directly applicable to healing human disease.“
Stem cells will hopefully someday be able to treat certain chronic diseases in animals and humans alike, for which there currently exists no cure, Owens added.
“We would like to be able to put [these cells] into the patient who has diabetes. If we can make those cells produce insulin again, they are no longer diabetic. Where we are now is trying to figure out how to speak the same language as these cells … and be able to tell them what we want them to do.“
Borjesson agreed, adding that currently stem cells are used solely in injuries, but are not limited to them in any circumstances.
“There is also research going on in spinal chord injuries, oncology and other diseases. And all the donor typing can be excluded, and certain retinas, livers and lungs don’t have to be transplanted; we just use these cells to benefit the patient,” Borjesson said.
MICHAEL MILLER can be reached at campus@theaggie.org.
