Scientists believe they have found a reliable way to transform donor blood into the universal type needed for safe, emergency blood transfusions.
The discovery is enzymes from gut bacteria that can efficiently turn type-A human blood into type-O.
Type-O blood is special because it can be donated to anyone without the risk of a bad mismatch reaction.
The researchers, from the University of British Columbia, say clinical trials of the treatment could begin soon.
The gut bug enzymes remove markers from the surface of the donor red blood cells present in type A but not in type O.
Stripping them away means the recipient’s immune system will think the donor type-A blood is type-O and will not attack it for being “foreign”.
Giving someone blood from the wrong group can be life-threatening.
While type-O patients can receive only type-O red cell transfusions, type-O donations are compatible with all other ABO types.