FREDERICTON - The use of stem cell technology to repair tendon and ligament damage in horses could lead to good news some day for humans hobbled by similar problems.
Unencumbered by many of the prohibitions governing the use of stem cells in humans, veterinarians in Canada are speeding ahead with the latest developments to treat injured, high performance horses.
The Atlantic Veterinary College at the University of Prince Edward Island is partnering with VetCell Bioscience Ltd. in England to introduce a new equine stem cell therapy to Canada that aims to make lame horses as good as new.
Dr. Laurie McDuffee, associate professor in large animal surgery at the veterinary college, says the new technology involves multiplying stem cells taken from the bone marrow of an injured horse and re-injecting them into damaged tendons or ligaments.
She is hoping a variation on the technology can be used to help heal bone fractures in the future.
"The implications for people from anything we do with animals is that we collect more data on certain technologies and that can be translated to a certain extent to humans," McDuffee says.
"For instance, one of the similar problems humans may get is Achilles tendonitis. Any of the data we collect on how this treatment works with horses with similar types of tendon lesions could be useful in the use of such therapy in humans."
The therapy is showing promise in horses.
It is used most often to treat valuable, high-performance animals such as racehorses and cutting horses, which are prone to ligament and tendon injuries.
McDuffee says the technology is too new in Canada to discuss long-term outcomes, but she says horses treated to date with the therapy are showing clear signs of improvement.
The technology has been available for a couple of years in Europe, and the results there have been positive.
A British racehorse called Knowhere recently thundered back to the track and was once again winning races after being treated with stem cells for serious tendon injuries to his forelegs.
Canadian veterinarians say they are excited about the new treatment.
Dr. Nathalie Cote of the Milton Equine Hospital near Toronto says she has started using the stem cell therapy and is enthusiastic about its apparent ability to restore damaged tissue.
She says that, in the past, the problem has been that torn tendons and ligaments often lose strength when they heal. She says scar tissue just doesn't have the same elasticity and strength as the original tendon tissue.
"In racing it's very frustrating because we haven't had a miracle treatment and we've been losing a lot of horses every year," says Cote, whose hospital is close to the Mohawk Racetrack at Campbellville, Ont.
"The problem is the recurrence. The horse rests for six months or a year and then you run the horse and it happens again and the reason for that is that these tendons do not heal as strongly or with elasticity . . . The stem cell treatment improves the quality of repair."
Improved repairs may be the main benefit for humans as well.
Tendon and ligament injuries present a major clinical challenge to orthopedic medicine. In the United States and Canada, an estimated 300,000 patients undergo tendon or ligament repair each year.
Researchers at Hebrew University have published findings showing success in transplanting bone marrow stem cells to repair injured tendons in rats.
According to published results, the cells changed their appearance to look more like tendon cells and significantly increased production of collagen, a protein critical for creating strong yet flexible tendons and ligaments.
McDuffee is travelling across Canada, introducing veterinarians to the technology and the work performed at the Charlottetown laboratory.
Stem cells from horses anywhere in the country must be shipped to the lab at the Atlantic Veterinary College where the cells are multiplied for re-injection.
The bone marrow cells are removed from the sternum of the injured horse, which has to be sedated for the procedure.
Once the laboratory receives the bone marrow sample, the stem cells are isolated and expanded to a certain number, then shipped back to the vet. McDuffee says the cells are transplanted into the injured area using ultrasound guidance.
"It's easy," says Cote.
"I really think it's a technology we will use more and more."
While there are still many unknowns about stem cells, it is believed they have the potential to turn into different cell types in the body, and theoretically can divide without limit as long as the person or animal is alive.
They have the potential to act as a sort of repair system for the body.
"We feel pretty comfortable that we definitely have good evidence for its use," McDuffee says of the equine stem cell therapy.
"In humans there are a lot of other issues relating to regulations and so on, but in this case, it's the horse's own cells going back into the horse and there aren't really any regulations. So we can get a lot of data which can help in moving this treatment towards humans."
