Immune Therapy Avoided After Kidney Transplant
Transplant surgeons have been able to successfully discontinue immune suppressing therapy after kidney transplantation using a new technique called mixed chimerism.
Reporting at the Experimental Biology 2001 meeting in Orlando, Florida, on Monday, Dr. Benedict Cosimi of Massachusetts General Hospital in Boston, announced that the approach has been successful in the first two patients attempted to date.
Because of the possibility of organ rejection, transplant recipients are usually placed on lifetime immunosuppressive drug therapy that can leave them open to complications, such as serious infections.
In the hopes of avoiding this, Cosimi and colleagues infused the patients with some of the bone marrow of the living donors of the kidneys at the time of the transplantation. The idea was that immune agents derived from both donor and recipient would co-exist within the recipient's immune system.
This ``mixed chimerism'' would hopefully allow transplant patients to maintain healthy immune function while reducing their risk for transplant rejection, thereby alleviating the need for the immune-suppressing drugs.
Immunosuppressive therapy was given for about 3 months following surgery and then discontinued. Cosimi told Reuters Health that the first patient has been off therapy for 2.5 years and the second has been off therapy for more than 6 months. The new kidneys are ``perfectly normal and we don't anticipate any rejection in the future.''
``This is the first time this has ever been done,'' Cosimi said. ``We know that tolerance can develop and that some patients have been able to discontinue immunosuppressive therapy, but we didn't know why. This is the first deliberate up-front effort'' to create tolerance, he said.
Cosimi said two clinical trials are about to begin, one in patients with kidney failure and multiple myeloma (a cancer of the bone marrow) and the other in patients with comparatively uncomplicated kidney transplants. |
