RESEARCHERS from the Albany Medical Centre (AMC) in New York, have devised a new technique which will lead to a blood type that would be compatible with all blood types. They have developed a process to coat red blood cells with a polymer called polyethylene glycol, or PEG, that would make it possible to transfuse any type of blood into any patient. Red blood cells are not affected by the chemical coating. The technique will have important clinical benefits, especially for patients with rare blood types, says Mark Scott, who is leading the research team at AMC.

Human blood is divided into four blood types - A, B, AB and o, depending on the antigens present on the surface of blood cells. If the wrong blood type is given to a patient, these antigens can trigger powerful and destructive reactions. But this problem can now be overcome by coating the blood cells with PEG so that the antigens are not detected by the immune system. "This prevents the destruction of foreign blood types," says Scott.