Researchers at UBC are one step closer to creating a universal blood type. In a studyrecently published in JACS, they demonstrated the ability to convert different types of blood into universal type O.
There are four major blood types (A, B, AB and O) that differ based on the presence or absence of antigens on the surface of red blood cells. Type O blood, is considered to be a universal donor as it is lacks the A and B antigen and doesn’t trigger unwanted, potentially life-threatening immune responses, which can arise if type A, B, or AB are given to an incompatible donor.
Enzymatic removal of the terminal sugar on the A and B antigens, has been proposed as a way to convert red blood cells into a universal, antigen-null, donor type. However, the enzymes discovered up to this point in time have not been efficient enough to make this idea practical.
The researchers at UBC screened over 20 000 DNA samples derived from human gut bacteria and discovered a novel class of enzyme that was able to effectively cleave the sugar from A and B antigens. Using directed evolution, they were able to engineer the gene product to produce an enzyme that is approximately 30 times more efficient than the previous best candidate, suggesting that enzymatic removal of blood group antigens is an attractive method for allowing the transfusion of blood from an otherwise incompatible donor.
More research and safety testing are needed before this approach would be applied to clinical practice. However, the results from this study are very promising, and bring us one step closing to alleviating the chronic shortages of universal type O blood.