Newly Discovered Enzymes Could Help Make Universal Donor Blood Possible

Researchers from the Technical University of Denmark (DTU) and Lund University have made a breakthrough that could facilitate the development of universal donor blood. In a study published in Nature Microbiology, they report the discovery of enzymes that can remove specific sugars that make up the A and B antigens in the human ABO blood groups when mixed with red blood cells.

Professor Maher Abou Hachem, the study leader at DTU, expressed excitement about the findings, stating, "For the first time, the new enzyme cocktails not only remove the well-described A and B antigens, but also extended variants previously not recognized as problematic for transfusion safety." He acknowledged that while they are close to producing universal blood from group B donors, more work is needed to convert the more complex group A blood.

The team tested 24 enzymes in their quest to find one that could remove both the A and B blood antigens and the sugars that block them. They focused on new mixtures of enzymes from the human gut bacterium Akkermansia muciniphila, which feeds by breaking down the mucus that covers the surface of the gut. It turns out that these enzymes are exceptionally efficient, as the complex sugars at the surface of the intestinal mucosa share chemical resemblance with those found at the surface of blood cells. "What is special about the mucosa is that bacteria, which are able to live on this material, often have tailor-made enzymes to break down mucosal sugar structures, which include blood group ABO antigens," adds Maher Abou Hachem.

The need for donor blood is high due to an aging population and more patients undergoing blood-intensive medical procedures. Successfully converting A or B blood types into ABO universal donor blood can markedly reduce the logistics and costs associated with storing four different blood types, increase the supply of donor blood, and reduce waste.