Dr. Susan Detmer collects a nasal swab for
culture to ensure the pig is free of communicable (zoonotic) diseases. “Pig organs are similar in size to human organs,” says Tom Spizzo, executive director of the Spring Point Project. “And it has been shown that insulin is compatible between humans and pigs.” In the 1920s, the first successful commercial insulin preparations were harvested from the pancreases of cows and pigs entering the food system. Until the first synthetic insulin was developed in 1978, diabetics widely relied on commercial purified pig insulin. Pigs could also provide a ready supply of islet cells. “Pigs can be housed within barrier facilities and they generate large numbers of young—approximately 10 to 12 piglets per litter,” says Spizzo. The Spring Point Project currently operates a biosecure facility in western Wisconsin where it raises specially selected pigs in compliance with government regulations for islet cell transplantation.
Graduate student Dr. Susan Detmer spends time interacting with future islet donor pigs. | In type 1 diabetics, islet cells have been destroyed, preventing those afflicted with the disease from producing insulin. Because insulin is needed to remove circulating glucose from the bloodstream, type 1 diabetics must rely on injections of commercial insulin. New immunosuppressive drugs, which became available in the mid-1990s, have greatly expanded research into islet cell transplants. However, the availability of human islet cells is limited. Researchers at the University of Minnesota Medical School pioneered human islet cell transplantation research in the mid-1970s. The transfer of animal tissues into human tissues, called xenotransplantation, resurfaced in the mid-1990s, and the College of Veterinary Medicine has become a leader in the field by helping to establish the value of pigs as donors. Pigs appear to be an ideal choice for islet cell xenotransplants. 
Dr. Jim Collins, director of the Veterinary Diagnostic Laboratory “We are pig savvy in Minnesota,” says Dr. Bernhard Hering, director of the Islet Transplant Program at the Schulze Diabetes Institute. “Our knowledge of pigs and experience with pigs distinguishes us from other states with biotech industries.” In addition to the numerous environmental precautions taken by Spring Point to safeguard its biosecure facility from germs, the VDL performs multiple tests to ensure the animals are free of all infectious agents that potentially could be transmitted to humans. |
