Blood banks around the world will frequently make impassioned calls to the public to make vital donations, especially when there is a shortage of a particular type. According to the Irish Blood Transfusion Service, as many as one in four people will need a blood transfusion at some point in their lives.

Yet new research from the University of British Columbia could soon render those distinctions obsolete, as a group of scientists headed up by Stephen Withers has successfully converted a unit of type A blood into type O blood.

In a paper published in  Nature Microbiology, the researchers explained that they were able to remove sugars from the surface of red blood cells by using a pair of enzymes they isolated from the gut microbiome of an AB positive donor.

Withers said the team could cleave the subtypes efficiently, “plus we have taken this enzyme and converted a whole unit of blood and shown that, according to all the measures used by the Canadian Blood Services, it is now type O. It gives us great confidence, but of course there are a lot of safety tests still to be done.”

The next step, Withers went on to explain, is for the team to test the safety of the process in greater detail. The researchers can do this by mixing the “converted” samples with other samples to see if there is an antigen-antibody response. This response mimics how the immune system of a recipient may react to blood from a donor of the wrong type.

“Two concerns that one would have is that we don’t completely remove the A or that we are causing some other change on the red blood cell surface, though we have no reason to think that at the moment,” Withers added.

The researchers at British Columbia thanked the Canadian Light Source (CLS) at the University of Saskatchewan for aiding them in understanding a previously unknown enzyme that was part of this pair. Crystallography carried out at CLS helped the team understand how the enzyme worked and explain its affinity for type A blood.

In total, there are eight different blood types, each type being defined by the presence or lack of certain antigens and antibodies.

Eva Short

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