Desensitisation gives new hope for non-compatible donor kidney transplants

According to an article in The New York Times, a study conducted at 22 US medical centres has found a way of altering a kidney recipient’s immune system by stripping away their existing antibodies, so that their bodies don’t reject organs from incompatible donors.

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The study shows that patients who underwent this process called desensitisation had a better survival rate than people who remained on the waiting list or received a kidney from a dead, but compatible donor.

Higher survival rate

During the eight-year study, 76,5% of the 1,025 patients, who received an incompatible kidney were still alive, compared with 62,9% who remained on the waiting list or received a deceased donor kidney and 43,9% who remained on the waiting list but never got a transplant.

How desensitisation works

One of the specialist units involved in the programme, Northwestern Memorial Hospital Transplant Programme, explains how the desensitisation process works.

“Immunosuppressant drugs and plasmapheresis are used to remove rejection-causing antibodies from the bloodstream. This process is done both before and after transplant, allowing many patients who would otherwise reject their transplanted kidney to successfully receive their transplant,” it says.

Regenerated antibodies don’t attack the transplanted organ

“The patient is 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, Dr Dorry Segev, the lead author of the new study – which appeared in the New England Journal of Medicine recently, and a transplant surgeon at the Johns Hopkins University School of Medicine told The New York Times.

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, he says.

Could also work with other organ transplants

Although the study was confined to kidney transplant, the researchers involved don’t see any reason why it can’t be expanded to other living-donor transplants, such a liver and lungs.

“The liver is less sensitive to antibodies so there is less need for desensitisation, “but it’s certainly possible if there are known incompatibilities,” Dr Segev says.