Last updated: 02/17/2009

To qualify as a candidate for islet cell transplantation, the patient must suffer from type 1 (juvenile) diabetes and current insulin treatment methods must be insufficient. For example, some participants suffer from hypoglycemic unawareness, a condition...

where low blood sugar will cause very dangerous, unpredictable blackouts that cannot be controlled with insulin injections. The potential patient must also undergo extensive medical and psychological tests to determine their physical and mental appropriateness for enrollment in the trial. If the results of these tests support the candidacy, then sufficient donor pancreas tissue in the patient's blood type must be located. The patient is placed on an organ donor list. Waiting for more than a year is common.

In response to this long wait, research is ongoing to provide alternative sources of donor islet cells such as animal cells, a process known as a xenograft. Pigs are a particularly advantageous source of islet cells because human and pig insulin proteins differ by only one amino acid, and there is an extensive amount of fresh pancreases available from the pork industry. Other potential sources of donor islets cells include embryonic stem cells and cell lines of islet beta cells.

Prior to the transplantation, the patient must undergo a drug regime that suppresses the immune system so that the new cells will be accepted. Even though only cells are being transplanted, the amount of immunosuppression is the same as that required for a whole organ transplant. Current protocols for islet transplantation use a mixture of non-steroidal drugs, as those that include steroids have been shown to aggravate the diabetic condition of the patient and inhibit the insulin-producing function of the transplanted cells.

Future research in this area may include the use of monoclonal antibody therapy to induce tolerance in patients prior to transplantation.