My discussion will focus on the use of porcine islets as an alternative to human islets for transplantation. In my opinion, allotransplantation (human-to-human) will remain the gold standard. I hope to convince you by the end of this talk, however, that in the future, there may be a need to consider alternative sources of organs.
ORGAN DONOR SHORTAGE
The number of patients on the organ transplant list in the United States has increased dramatically from less than 20,000 in 1988 to greater than 75,000 in 2001. During the same 12 years, the number of cadaveric donors has remained fairly constant, ranging between 4,500 and 5,900. A fraction of the shortfall between the number of patients on the waiting list and the number of cadaveric donors is made up by those altruistic people who offer organs to their relatives or friends: living donors (see Figure 1).
The United Network for Organ Sharing (Richmond, Va) updates its organ transplant waiting list weekly on its website, www.unos.org. As of February 24 of this year, almost 2,500 people are waiting for combined kidney-pancreas transplants; greater than 1,000 for isolated pancreases; and 185 for islet cell transplants. Because patients are added to the waiting list each day, investigators have been forced to develop methods of expanding the donor pool.
Secretary Tommy Thompson of the United States Department of Health and Human Services had great success as Governor of Wisconsin in encouraging organ donation. He stated that during the first 100 days of his administration, he hoped to …