Recent research indicates a possibility that immuno-suppressant drugs after organ transplant not be required for the rest of the recipient's life.

The current edition of the New England Journal of Medicine reports on five kidney transplant patients and one liver transplant patient where dependence on immuno-suppressants was reduced.

The five kidney transplant patients also got bone marrow transplants from their kidney donors. They got drugs or radiation before their bone marrow transplant to prepare their immune systems and they were weaned off immune-suppressing drugs without suffering organ rejection. This took over 14 months to accomplish.

It's not that the patients had no problems after their transplants; several had leaky blood vessels that needed treatment. A sixth patient suffered kidney rejection and needed a second kidney transplant, after which he started standard immune-suppressing drug therapy.

The doctors who worked on those kidney transplants include Tatsuo Kawai, MD, of the transplantation unit at Massachusetts General Hospital and John Scandlin, MD, of Stanford University.

The liver transplant patient was a 9-year-old girl in Australia. Her blood type was O negative.  She got a liver transplant from a donor whose blood type was O positive. After her transplant, her blood type changed to O positive, the same as her liver donor.

Why did her blood type change? That's not clear. But she had a virus that caused a big drop in her white blood cells (which are part of the immune system) that lasted for six months after her liver transplant.

The girl developed severe hemolytic anemia (a serious blood condition) 10 months after her transplant. At that point, the doctors gradually eased her off immune-suppressing drugs. She recovered without rejecting her transplanted liver, according to her doctors, who included Stephen Alexander, MB, BS, of the University of Sydney's Centre for Kidney Research.

It will take more work to figure out "just the right dose and timing of immunosuppressive therapy" with or without bone marrow stem cell transplants, writes editorialist Thomas E. Starzl, MD, PhD, of the University of Pittsburgh's Thomas E. Starzl Transplantation Institute.