Millions of diabetics battle their illness with daily doses of insulin injections. However in people suffering with juvenile diabetes, transplants of the pancreatic tissue could help solve the problem. Diabetes brings with it complications like blindness, amputation, kidney failure, and heart disease.
Unfortunately, there are not nearly enough organ donors available for transplantation. Insulin-producing pancreas tissues from animals could potentially provide a nearly unlimited supply for transplantation. But until now, attempts to transplant such animal tissues into non-human primates have evoked a fierce immune response. However, embryonic tissues, such as those from pigs (in which the insulin-producing cells are similar to those of humans), might not be rejected as strongly. New research by Prof. Yair Reisner of the Weizmann Institute's Immunology Department has brought the possibility of transplants from pig embryos one step closer. The results of the study appeared in the June issue of PLoS Medicine.
In previous work, Reisner and his team had shown that each embryonic organ has its own 'time window' during which the chances for successful transplantation are optimal. Prior to this window, the early tissue's cells, which are still largely undifferentiated, can give rise to tumors. Past the window, however, they may be too well-developed: The host identifies these cells as foreign, causing the body to reject them. By transplanting tissues from pig embryos into mice lacking proper immune systems, they determined that the best time frame for pancreatic tissue was about a third of the way through gestation (from 42 to 56 days).
"The results of this study," says Reisner, "warrant further, pre-clinical research on primate models."
Contact: Jennifer Manning
American Committee for the Weizmann Institute of Science