Is there life without immunosuppression? This is the question that Dr. George Mazariegos and his colleagues are trying to answer at the University of Pittsburgh’s Thomas E. Starzl Transplantation Institute. Their study on liver transplant patients and the role of immunosuppression began in 1992. It started when they found that some liver transplant recipients remained healthy long after they had quietly stopped taking their prescribed immunosuppressant. Their findings were presented in Chicago in May this year at transplant 2000, the first combined conference of the American Society of Transplant Surgeons and the American Society of Transplantation.

For the study, they selected people who had lived for atleast five years with a donor liver, had no rejection episodes in the two years before study enrollment and, at that time, had normal liver function. So far, nearly a third of the 120 adult and pediatric participants have not taken immunosuppressant for an average of about 6 years, and their liver functions remained normal. Another third had an episode of acute rejection which was successfully treated, and resumed their initial drug regimen. Others were in the process of being weaned off the drugs.

Mazariegos said that children were more likely to be able to do without the drugs than adults. He also said that liver damage caused by autoimmune diseases were more likely to result in rejection or recurrent disease than patients who had cirrhosis from another cause.

Researchers from the University of Pittsburgh and children’s hospital say that genetic profiling may help predict who needs immunosuppressant and who doesn’t. Dr. Adriana Zeevi and her colleagues checked the cytokine gene profiles of 76 children who had received heart transplants. They found that those who produced low level of TNF-alpha and high levels of Interleukine-10 were least likely to reject the transplanted organ. Zeevi also tested 9 of the liver transplant patients who came off immunosuppressant in the Mazariegos study and found that they all fit the same profile of producing high level of interleukine-10. Dr. Steven Weber from the children’s hospital said that gene profiling could tailor the immunosuppression regimen to the needs of the patients on an individual level. He added, “Within a year or so we will know if it really holds true.”