Researchers at the University of Minnesota have reversed the course of diabetes in monkeys by transplanting islet cells from pigs — giving renewed hope that a better treatment, or even a cure, may soon be available. The transplant research, published Sunday, addresses a key problem in diabetes: the lack of so-called islet cells in the pancreas that create insulin. Human islet cells work for transplants, but there are not enough to treat the millions of people with diabetes.

More research is required before pig-to-human transplants can take place, but the latest results are so encouraging that an affiliated nonprofit group is building "biosecure" farms that will raise ultra-healthy pigs for clinical trials.

University doctors performed the world's first islet cell transplant in 1974 and have led research in this field. Some transplants have allowed diabetics to stop taking insulin injections altogether, but even human islet cell transplants remain experimental.
The problem is the number of diabetics who could benefit from a transplant outweighs the number of donated islet cells. Initially, doctors needed to gather cells from more than one pancreas to have enough for a transplant. U researchers are now succeeding with islet cells from a single human donor, but that won't address the shortfall.

"This is a very critical milestone in our ability to provide tissue for transplants on an unlimited basis," said chief researcher Hering.
Hering's optimism is largely due to his research on how to prevent the human immune system from rejecting transplants of animal cells. Patients already receive drugs to prevent their immune systems from rejecting human cells or organs, but the fear is that even more drugs will be needed to carry out pig-to-human transplants. Immunosuppressive drugs can have severe side effects and leave patients at great risk if they suffer infections.

Researchers at Duke University Medical Center reported in 2001 that they treated a diabetic baboon by transplanting pig cells that were specially coated to fool the immune system. Hering said his research doesn't involve any coating or genetic modifications to the pig cells, but rather involves the discovery of "critical pathways" in the body that allow the pig cells to function without triggering the immune system.

Hering's research, published in the journal Nature Medicine, was supported by private funding and later with money from the National Institutes of Health. There is no simple funding source to build farms to raise the pigs that will be used for islet cell transplants, which is why Spring Point Project was developed.