In the anguishing wait for a new kidney, tens of thousands of patients on waiting lists may never find a match because their immune systems will reject almost any transplanted organ. Now, in a revolutionary study, researchers have successfully altered patients’ immune system to allow them to accept kidneys from an incompatible donor. Significantly, more of those patients were still alive after eight years than patients who had remained on waiting lists or received a kidney transplanted from a deceased donor.
The method, known as desensitisation, “has the potential to save many lives,” said Dr Jeffery Berns, a kidney specialist and the president of the National Kidney Foundation, adding that the procedure could mean the difference between receiving a transplant and spending the rest of life on dialysis.
Researchers estimate about half of the 1,00,000 people in the United States on waiting lists for a kidney transplant have antibodies that will attack a transplanted organ, and about 20% are so sensitive that finding a compatible organ is all but impossible. In addition, said Dr Dorry Segev, the lead author of the study, an unknown number of people with kidney failure simply give up on the waiting lists and resign themselves
to dialysis, a difficult and draining procedure that can pretty much take over a person’s life.Desensitisation involves first filtering the antibodies out of a patient’s blood. The patient is then given an infusion of other antibodies to provide some protection while the immune system regenerates its own antibodies. For some reason — exactly why is not known — the person’s regenerated antibodies are less likely to attack the new organ, Segev said. But if the person’s regenerated natural antibodies are still a concern, the patient is treated with drugs that destroy any white blood cells that might make antibodies that would attack the new kidney.
The desensitization procedure takes time — for some patients as long as two weeks — and is performed before the transplant operation, so patients must have a living donor.