Hemophilia, a rare, life-threatening bleeding disorder, has been successfully reversed in animal studies, suggesting it may not be long before therapies for humans are developed.
A single dose of genetically modified stem cells successfully converted hemophilia in two sheep to a milder form of the disorder, researchers at Wake Forest Institute for Regenerative Medicine in North Carolina reported in the journal Experimental Hematology.
Researchers inserted a blood-clotting gene into adult stem cells, which were injected into the sheep's abdominal cavity. The cells traveled to the animal's joints to stop ongoing bleeding, as well as stopping all spontaneous bleeding events. Researchers noted that the animals were able to resume normal activity levels.
However, the sheep developed an immune response to the clotting gene, which indicates the treatment's effect may be short-lived. The scientists are attempting to discover why this response occurred and how it may be prevented.
There is currently no cure for hemophilia, in which the blood doesn't clot in a normal fashion. Patients with this condition can bleed for long periods of time after an injury, which can lead to pain, lack of mobility and death. About 400 babies are born with hemophilia in the U.S. each year.