Adults with sickle cell disease have had a rough time with the best-available treatment because of the reliance on medications that prevent immune system rejection of donor cells. These medications cause a number of serious problems.
Furthermore, many sickle cell disease patients have organ injury that makes them ineligible for transplant treatment. Researchers at the National Institutes of Health have found a possible treatment approach that may circumvent the organ injury restriction and allow treated patients to stop taking immunosuppressing medications. This technique uses donor stem cells taken from a sibling of the patient mixed with cells from the patient for replacing the original stem cells that make blood cells, the bone marrow stem cells.
The report published in the July 2 issue of the Journal of the American Medical Association documents a high percentage of 30 patients with very severe sickle cell disease treated with the sibling-donor approach showing improvement and cessation of immunosuppressing medications to prevent transplant rejection within a year after the transplant procedure.
This experimental technique mixes stem cells from a sibling with the patient’s own cells. Of 30 patients treated this way, many stopped using anti-rejection drugs within a year and avoided serious side effects of transplants, rejection and graft-versus-host disease, in which donor cells attack the recipient cells, the researchers said.
“We can successfully reverse sickle cell disease with a partial bone marrow transplant in very sick adult patients without the need for long-term medications,” said researcher Dr. John Tisdale, a senior investigator at the U.S. National Heart, Lung, and Blood Institute.
In the United States, more than 90,000 people have sickle cell disease, a painful genetic disorder found mainly among blacks. Worldwide, millions of people have the disease.
Dr. Henry Fung, director of the Temple Bone Marrow Transplant Program says the best treatment is a bone marrow transplant after the immune system has been deliberately destroyed by high doses of chemotherapy.
It works for children, he points out, but adults suffer and can’t tolerate the treatment.
“The longer you are with sickle cell disease and you receive treatment, in particular blood transfusion, you are prone to develop complications,” Fung says.
But this study shows that using lower, less toxic doses of chemotherapy will work and adults will do well.
Over 90,000 people in the U.S. have sickle cell disease and millions suffer from this painful genetic condition worldwide. Sickle cell disease primarily occurs in blacks. The bone marrow cells that make disc-shaped red blood cells normally make crescent- or sickle-shaped red blood cells in sickle cell disease.
The sickle-shaped red blood cells do not function properly in their role of carrying oxygen to and carbon dioxide away from tissues and organs. They also block blood flow and the blood-starved tissues deteriorate and cause severe pain in doing so.