When all other treatments fail, deadly blood disorders can be cured by destroying the patient's own blood system, then regenerating it with blood stem cells from a healthy donor.
But if the patient and donor lack closely matched immune system markers, the transplanted cells become a threat, attacking rather than revitalizing their new host.
Now, Thomas Jefferson University researchers have developed a way to make stem-cell transplants work, even when only half the immune markers are matched.
The advance, a goal of research around the world, has big implications. Fewer than half of white people and only 10 percent of minority groups can find closely matched stem-cell donors among siblings or registries of volunteers. "Half-match" transplants would triple the pool of suitable donors, giving new hope to patients with terminal leukemia, lymphoma, sickle-cell anemia, and other blood diseases, said Dolores Grosso, lead author of a Jefferson study published online in the journal Blood. "You could help almost everybody," she said.