MELISSA BLOCK, host:
Organ transplants have saved thousands of lives over the past 50 years. To prevent rejection of those organs, patients have to take toxic drugs for the rest of their lives. Several papers in this week's New England Journal of Medicine shed light on a new experimental alternative for some transplant patients.
NPR's Richard Knox reports.
RICHARD KNOX: Jennifer Serle can tell you all about the complications of anti-rejection drugs. She got her first kidney transplant at the age of 13, and then suffered drug side effects ranging from weak bones and memory loss to viral warts that made her feet so painful she couldn't walk.
Ms. JENNIFER SERLE (Kidney Transplant Patient): I knew I had to do something drastic because, you know, I was young. To think of 20, 30, 40 years living like that, I didn't want any part of it.
KNOX: So Serle, now 28, volunteered for a study at Massachusetts General Hospital. After years of experiments in animals, researchers were ready to see if they could dispense with immune-suppressing drugs and all their side effects in people. To Jennifer's delight, it worked.
Ms. SERLE: So now, it has been five years, and I have not taken any medications that a normal transplant patient would take.
KNOX: Her bones have strengthened, she's mentally sharp, and the warts disappeared.
Ms. SERLE: I'm definitely walking. I actually ran two marathons in October. It's basically been the healthiest that I've ever been in my life.
KNOX: Jennifer Serle marks a turning point in getting patients to tolerate genetically different transplants. In her case, she got a kidney from her mother who was only a partial match.
Dr. DAVID SACHS (Transplantation Biology Research Center, Massachusetts General Hospital): This is the first time when it was done intentionally in a human being, and we are delighted with the outcome.
KNOX: That's Dr. David Sachs who led the Mass General team. He says the key for Jennifer was transplanting not just her mother's kidney but also a bit of her mother's bone marrow. That gave Jennifer an immune system that was essentially a blend of her own and her mother's. So immune cells called T-cells that normally attack anything foreign are fooled into ignoring the transplanted kidney or tolerating it.
Dr. SACHS: So now, you end up with T cells that can react against everything else in the environment - bacteria, viruses, any other antigen - except recipient and donor. So that's what we call tolerance.
KNOX: The trick succeeded in three other Boston patients. Other patients in the same journal detailed two patients who achieved tolerance by other maneuvers. Those patients also are doing without immune-suppressing drugs. That doesn't mean this approach works for all transplant patients. It's still experimental. And Sachs says the treatment his patients require before the transplant takes several days. That precludes organs from brain-dead donors. There's too little time.
Dr. SACHS: The only requirement right now is that it has to be from a living donor. We haven't yet got this procedure working in a situation where it's a deceased donor, which is, of course, the usual case for many other transplants, such as the heart.
KNOX: Dr. Tom Starzl, a transplant pioneer at the University of Pittsburgh, doesn't see the Boston group's method as a breakthrough.
Dr. TOM STARZL (Transplantation Surgery, University of Pittsburgh): I think the preparations that they used is too complex to be used clinically.
KNOX: In Pittsburgh, Starzl says, they're fine-tuning their transplant regimens to achieve partial tolerance.
Dr. STARZL: When we get somebody down to one dose a week or two doses a week of a conventional drug - and this would be a patient who normally would be on maybe two or three drugs in high doses every day or twice a day - we see no real reason to go from one dose a week to nothing.
KNOX: But the Boston group has another big goal in mind. David Sachs says achieving tolerance in mismatched human transplants is a step toward the day when animal organs might be safely put into people.
Richard Knox, NPR News, Boston.