Blood substitutes have been a black hole for biotech companies. There are no such products approved by FDA or EMEA after nearly two decades of effort. Nevertheless, candidates that attempt to replace the oxygen-carrying ability of red blood cells using either human- or bovine-derived hemoglobin or synthetic perfluorocarbons are still in development. Earlier this month, researchers from ZymeQuest Inc. and colleagues reported progress in making one of the oldest ideas for creating universal red blood cells into reality.

Enzymatic removal of blood group ABO antigens in order to create universal RBCs was first proposed more than 25 years ago. But, according to the researchers, while the feasibility of the approach was shown for group B RBCs, the idea remained impractical due to the lack of efficient glycosidase enzymes to remove the A and B antigens.