A team of researchers headed by University of British Columbia scientist Stephen Withers reports on enzymes - from the human gut - that remove A or B antigens from red blood cells 30 times more efficiently than previously reported enzymes.
The researchers found specific enzymes from gut bacteria can strip antigens from the surface of red blood cells in Type A blood donations, essentially transforming it to Type O blood.
The prospect of turning donated blood to a common type - O, the universal donor type - is understandably quite appealing to researchers and medical professionals.
Withers is now collaborating with colleagues at the Centre for Blood Research at UBC to test these enzymes on a larger scale; depending on the results, they may be then selected for clinical testing. The O negative blood type is used extensively in blood transfusions because it can be used in replacement of all blood types. Instead of culturing microbe after microbe in a painstaking process, the research team simply extracted DNA from all the microorganisms found in the human gut. "Our hope is that one day we can eventually render any type of donated blood, tissues or organs, safe for use by anyone regardless of their native blood type".
While the researchers planned to start by sampling DNA from mosquitoes and leeches - both organisms that degrade blood - they ultimately found likely candidates in the human gut flora.
"The idea was demonstrated for B blood back in 1982, but the enzymes they had available then were so slow and inefficient it was never going to be a practical approach", Withers said.
"I am O-negative and know how rare and valuable this blood type is for the NHS", she said.
There are four types of blood, and unlike types A, B and AB, Type O blood is the universal blood donor and can be given to anyone. What's more, these enzymes were 30 times more effective at stripping off A antigens than the best-performing enzyme previously suggested for this objective, Withers reported.
"The next step is very much all about safety", he said. The Red Cross had to call for blood donations this January after the raging storms and the universal O type blood was in great need.
Having a process to quickly convert other blood types into Type O could make it simpler to donate blood during emergencies.
"One of the main challenges with maintaining an adequate blood supply in developed countries is that the use of group O is not in proportion to the incidence of that blood group in the population", said CBS chief scientist Dr. Dana Devine, who called the blood-converting enzymes a potential "game-changer".
"It looks like it completely converted to O", Withers said. "That's really important because we don't want to modify the red blood cell in some way that might compromise it", Withers said.