Shortages of particular blood types have the potential to delay lifesaving care, so it’s critical that hospitals have a reliable source of the most useful types. After years searching for a safe and effective method of converting blood to the universal donor type, scientists think the answer might have been in our bodies all along.
A person’s blood type is determined by molecules present on the surface of the cells called antigens. “If you can remove those antigens, which are just simple sugars, then you can convert A or B to O blood,” says Dr. Stephen Withers of the University of British Columbia. Type O blood, the universal donor type, is the most useful for hospitals to have on hand.
Some of the molecules that enzymes in gut bacteria can break down are similar in structure to the antigens associated with blood types A and B. Withers’ team explored the possibility of exploiting this similarity and using the enzymes to remove blood cell surface antigens. They found that these enzymes were 30 times more efficient than previously studied enzymes at converting other blood types to O.
“I am optimistic that we have a very interesting candidate to adjust donated blood to a common type,” Withers says.
Next, the team plans to use protein engineering to make their enzymes even more efficient before moving into clinical trials.