AGENCIES
LONDON, MAY 3
Soon scientists may be able to change all donated blood of any type into a universal type so that everybody becomes a universal donor. University of British Columbia researchers are on the verge of achieving a historic breakthrough as they have come close to discovering a process for snipping sugars off of A and B type blood cells and make them more similar the universal type O blood type.
The researchers have succeeded in creating an enzyme that could trim sugar antigens off of blood cells. Type O universal blood cells lack antigens on their surface, thus by trimming off antigens, the enzyme essentially converts Type A and Type B blood to Type O.
The enzyme at this stage is capable of removing most but not all of the antigens. The researchers said that since antibodies are highly sensitive inside the body it is not possible to use the enzyme in a clinical setting until it is engineered to remove all of the antigens, so they need to work more on it.
For their experiment, the researchers used directed evolution, which involves inserting mutations into the genes used to control production of the enzyme, and then the mutants are selected that were best able to remove the antigens. The researchers made the enzymes 170 times more effective in just five generations.
"We produced a mutant enzyme that is very efficient at cutting off the sugars in A and B blood, and is much more proficient at removing the subtypes of the A-antigen that the parent enzyme struggles with," said David Kwan, the lead author of the study and a postdoctoral fellow. In just five generations, the enzyme became 170-fold more effective, according to their study.
"The concept is not new but until now we needed so much of the enzyme to make it work that it was impractical," says Steve Withers, a professor in the Department of Chemistry. "Now I'm confident that we can take this a whole lot further."
