Kidney transplant without drugs

Doctors at Massachusetts General Hospital in Boston have been successful in transplanting kidneys without the need of anti-rejection drug dosage.

This has been achieved by simultaneously giving the bone marrow of the donor to the recipient, thus inducing a state of tolerance, in which the recipient's immune system does not recognize the new organ as foreign. This process is considered to be of real value as the kidneys that were used were not even close matches to the recipient’s, making them more susceptible to rejection.

Anti-rejection drugs, also known as Immunosuppressive drugs help in avoiding the rejection of the new organ as it is a foreign part in the body and thus, the body’s immune system develops a hostile response against the new organ. But some recent studies had linked these drugs to various cases of cancer, kidney damage and other side effects.

"There is reason to hope these patients will be off drugs for the rest of their lives," said Dr. David Sachs of Massachusetts General Hospital, who is the lead author of the report.

In this new procedure, the research team gave drugs and radiation to recipients to weaken their immune systems and destroy T cells as it is primary immune system component involved in tissue rejection.

After some days, transplant was done and simultaneously each patient received an infusion of bone marrow from the donor. Initially the patients had to be given but they were successfully taken off from these after eight to 14 months.

The results came out to be very interesting. Out of the five patients, two patients were successfully taken off these drugs and have been drug-free for more than five years. But in the third patient immune response was seen and thus one more transplant was done.

When the cause of this was studied in detail, it was found that high levels of another immune cell, called a B cell, caused the rejection. Thus, in the next two patients, team added antibodies against the host B cells and these patients are off the drugs for two to three years.

The study was funded by the Immune Tolerance Network, an international consortium of federal and advocacy groups. Sachs plans to study the procedure in 15 to 20 more patients, and another team at Northwestern Memorial Hospital in Chicago is planning to study it in 20 patients.

Transplant expert Dr. Thomas Starzl of the University of Pittsburgh said donor cells appeared to persist in the bodies of the successful transplant recipients even if those cells were not readily detected.

Dr. Suzanne Ildstad, a University of Louisville immunology specialist said that eliminating the need for anti-rejection drugs is "a huge advance but it still needs some fine-tuning so that everyone who gets treated gets the same consistent outcome. It's not the holy grail of tolerance yet, she mentioned.