Cooling platelets extends shelf life.

• Position: Blood Transfusions

An innovative method for treating and chilling blood platelets may prolong their shelf life by a week or more, helping to ease chronic shortages that endanger patients needing transfusions, maintains Karin Hoffmeister of Brigham and Women's Hospital and Harvard Medical School, Boston. Platelets, the cell fragments in blood that assist clotting, currently are stored at room temperature for a limit of five days. They then must be discarded as their risk of bacterial contamination increases sharply.

Shortages in donated platelet supplies can have serious consequences, because patients awaiting transfusions urgently need them. These individuals typically are bleeding severely following major surgeries, accidents, chemotherapy, or bone marrow transplants. "As the population gets older, we need more and more donations. And the number of younger donors is shrinking. The blood banking industry loses a significant amount of money by throwing these bags of platelets away," Hoffmeister insists.

Chilling them helps lengthen their storage period, but these platelets die quickly once they are transfused into the body. Using mouse and human platelets in test tubes, Hoffmeister found a way to extend the lives of...