Towards universal donor blood

For many years scientists around the world have been trying to find a way to convert the second most common blood type A into type O, by removing its antigens.

28 July 2020

donating blood for transfusions : Blood donation and blood donor,  hemolytic transfusion bank concept.

By Mariusz Bogacki, Researcher and Science Communicator, Edinburgh

Generally speaking, there are four blood types or blood groups in humans: A, B, AB, and O. These are defined by specific sugar molecules, called blood antigens. Accordingly, all human beings can be classified into four blood groups: those with antigens A, those with antigens B, those with both antigens A and B, and those with neither antigens (O). Blood group O, having no antigens, is the most uncommon type and remains in constant high demand. This is because blood transfusion can only be successful if a person receives the blood group with the same type of antigens or no antigens at all. In practice this means that blood group O is being used in most emergency transfusions when there isn’t enough time to determine the correct blood type of a patient. Not to mention scheduled operations or general routine transfusions when the group O is also regularly used. In short: having a constant supply of this type of blood would potentially save millions of lives annually.

For many years scientists around the world have been trying to find a way to convert the second most common blood type A into type O, by removing its antigens. Unfortunately, the process of removing antigens had never been efficient enough for a clean, complication-free transplant. Until now. Researchers at the University of British Columbia (UBC) in Vancouver, Canada, believe they have found a new technique, which promises a complete extraction of the unwanted antigens from blood group A.

The solution was found in the human gut - among the gut bacteria to be precise. Scientists at the UBC realised that some of these microorganisms are capable of ‘eating’ the additional blood type-defining sugar antigens. In doing so, completely removing the unwanted antigens from blood, making it a fully transplantable, universal blood type.

While promising, the results of the experiments are still preliminary and require further testing. Especially in order to determine whether the particular gut bacteria are not munching on other useful minerals. The scientists are very hopeful though, pointing out to the fact that together with blood group O, the supply of universal donor blood could almost double. A bloody good job indeed!