Every day, thousands of people need donated blood but blood transfusions require that the blood type of the donor match that of the recipient., unless it is blood without A- or B-type antigens, such as type O, that can be given to all of those in need. Mismatched blood with A or B antigens could provoke an immune reaction and even cause death. 

For that reason, Type O is often in short supply, but science may soon have a solution. Stephen G. Withers and colleagues write in Journal of the American Chemical Society of an efficient way to transform A and B blood into a neutral type O that can be given to any patient. 

They found that some enzymes from bacteria can clip the sugars off red blood cells that give blood its "type." But the enzymes are not very efficient. Withers' team wanted to see if they could boost the enzymes' activity.

The researchers tweaked one of those enzymes and improved its ability to remove type-determining sugars by 170-fold, rendering it antigen-neutral and more likely to be accepted by patients regardless of their blood type. In addition to blood transfusions, the researchers say their advance could potentially allow organ and tissue transplants from donors that would otherwise be mismatched.

The authors acknowledge support from the Canadian Blood Services, the Canadian Institutes of Health Research, Health Canada and the Michael Smith Foundation for Health Research.