Impaired adenosine-5'-triphosphate release from red blood cells promotes their adhesion to endothelial cells: a mechanism of hypoxemia after transfusion.

Summary: Blood transfusions are lifesaving, but in critically ill patients, they sometimes lead to unexpected lung complications. Researchers investigated why older, stored blood might cause these issues. They discovered that after about 14 days of storage, red blood cells lose the ability to release ATP, a vital chemical signal. Even if the cells contain ATP inside, they stop releasing it into the bloodstream. This lack of a signal causes the blood cells to become "sticky," adhering to the walls of blood vessels in the lungs rather than flowing smoothly. This blockage lowers oxygen levels in the blood. However, the study found a promising solution: adding an ATP supplement or blocking the sticky receptors on the cells prevented this damage in mice, suggesting new ways to make transfusions safer.