New enzyme may soon transform donated blood into universal type

Toronto: Researchers, including one of Indian-origin, have created an enzyme that could transform all donated blood into a universal type that can be given to any patient. Sometimes when a patient needs a blood transfusion their blood type is not in the blood bank. It is a problem that scientists have been trying to solve for years but have not   been able to find an economic solution - until now. University of British Columbia chemists and scientists in the Centre for Blood Research have created an enzyme that  could potentially solve this problem.  

The enzyme works by snipping off the sugars, also known as antigens, found in Type A and Type B blood, making it more   like Type O. Type O blood is known as the universal donor and   can be given to patients of all blood types. 

"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 the Department of Chemistry. To create this high-powered enzyme capable of snipping off sugars, researchers used a new technology called directed evolution that involves inserting mutations into the gene that codes for the enzyme, and selecting mutants that are more effective at cutting the antigens. In just five generations, the enzyme became 170 times more effective.  

With this enzyme, UBC associate professor Jayachandran Kizhakkedathu and colleagues were able to remove the wide   majority of the antigens in Type A and B blood. But before it can be used in clinical settings, the enzyme used would need to remove all of the antigens. The immune system is highly sensitive to blood groups and   even small amounts of residual antigens could trigger an immune response. "The concept is not new but until now we needed so much   of the enzyme to make it work that it was impractical. Now I'm  confident that we can take this a whole lot further," said   Steve Withers, a professor in the Department of Chemistry.