Transplants for Pets: The New Frontier
Although potentially lifesaving, the procedure has physical and ethical consequences for owners and animals.
Joanne Healey Howl, DVM |
Posted: Sat Feb 10 00:00:00 PST 2001
Page 2 of 4
Another problem to overcome is dogs' genetic diversity. More than any other animal, dogs have been bred into a wide variety of shapes and sizes - and thus a wide variety of genetic codes. "If you put a Newfoundland, a Shar-Pei and a Lhasa Apso into the same room, you might have a hard time recognizing that they are all dogs," Dr. Gregory said. "You don't have that problem in other species - a Persian and a Siamese both look pretty much like cats. Even the many human races are more alike than different. You can see with your own eyes that the differences are pretty superficial." In the transplant game, the more genetically alike the donor and recipient, the more trouble-free the transplant. Tissue matching in humans is not terribly difficult; identical twins can swap organs without any immunosuppressive drugs. Dogs are different. They are rarely closely matched genetically and rarely accept organs from another dog without a fight.
Although the odds were against her, Chloe's owner was determined to try to save her pet's life. Her veterinarian referred them to Karol Mathews, DVM, DVSc, service chief of critical care and emergency medicine at Ontario Veterinary College, University of Guelph in Guelph, Ontario. Dr. Mathews has dedicated her life to making organ transplantation in the dog a reality. After completing a surgical residency in 1986, during which she worked on transplanting pancreatic islet cells in the dog, she focused her work on the canine kidney. By 1989, the experimental kidney transplants carried out in her laboratory were so successful that she began offering the surgery to clients. When Chloe came to her, Dr. Mathews had done 15 clinical cases, with six of them surviving a year or more.
The key to Dr. Mathews' good results is rabbit anti-dog anti-thymocyte serum, or RADTS, a new drug that attacks lymphocytes, white blood cells responsible for graft rejection. It's a very powerful immune suppressant with one big problem: It's not manufactured commercially. Dr. Mathews makes it herself in her laboratory at Guelph. "It's veryt edious," she explained. "It can take up to a year to make one batch. Fortunately it keeps well, and one batch will treat a lot of dogs." Even with all its power, the serum needs help to override the dog's strong immune system. Dr. Mathews adds the more traditional immune-suppressive drugs azathioprine, cyclosporine and prednisone to help control the dog's aggressive attack on the new organ.Page 1 | 2 | 3 | 4
Give us your opinion on Transplants for Pets: The New Frontier
Login to get points for commenting or write your comment below
Get New Captcha