'Universal blood' beckons
2007-04-03 07:13
Paris - Researchers say they have discovered two enzymes that may safely convert blood groups A, B and AB to group O, the "universal" blood used in transfusions.
Under the ABO system of blood classification established in 1900, group O red cells can be given to all individuals.
But A can only be given to A and AB individuals, and B can only be given to B and AB individuals. Giving someone the wrong type can trigger a massive, sometimes fatal attack on the transfused cells by the host's immune system.
Researchers at the Laboratory for the Architecture and Function of Biological Macromolecules at the University of Aix at Marseille, southern France, say the two enzymes break down the sugary molecules that form the cells' antigens, or the triggers for the immune response.
These antigens are on the surface of A, B and AB cells, but not on O cells.
The enzymes are tailored together from two bacteria, one called Elizabethkingia meningosepticum and the other called Bacteroides fragilis.
The next phase will be to subject the enzymes to a full battery of safety tests before they can be used in blood banks.
If all goes well, and the process is not too expensive, the enzymes could be used to boost universal blood supplies, helping to overcome shortages.
The study was published in the April issue of Nature Biotechnology, a specialised journal of the Nature group.