One of the most effective forms of therapy when dealing with leukemia is stem-cell transplantation. In some cases, however, the immune cells of the donor also attack the recipients’ healthy tissue. Now, researchers from the University of Zurich have discovered a molecule that could be the key to significantly improving patient outcomes.
Often times, the only chance of full recovery for people suffering from leukemia or bone-marrow cancer is stem-cell therapy. The procedure involves eliminating the compromised cells using chemo or radiation and then substituting them with ones from a healthy donor. The newly introduced cells attack the disease, prevent the patient from suffering a relapse and produce new blood.
The treatment comes with significant risks. Estimates show that in 30% to 60% of cases, the donor cells also attack the recipients’ healthy tissue – with the liver, intestine, and skin being likely targets. This effect is called the graft-versus-host (GVH) response and can lead to loss of life.
Doctors noticed that the production of a cytokine called granulocyte-macrophage-colony-stimulating factor (GM-CSF) is a decisive factor in graft-versus-host pathology. GM-CSF helps make a specific group of white blood cells that fight infections. Testing showed that donor cells that were unable to create this factor also lacked the lethal response.
“Targeting this cytokine is, therefore, a very precise and specific form of immunosuppression, designed to stop the tissue damage caused by graft-versus-host responses,” noted Prof. Dr. Burkhard Becher in a press release.
Initial concerns that neutralizing GM-CSF would also diminish the donor cells’ anti-cancer effect were dispelled. The procedure could soon be much more successful and present fewer risks to the patient.
“This therapeutic strategy holds particular promise for patients with the poorest prognosis and highest risk of fatality”, added Becher.