In the field of transfusion medicine, ABO blood group compatibility is the by far the most important aspect to consider. This is due to the presence of naturally occurring antibodies in the plasma directed against the highly immunogenic A and B antigens found in abundance on the red blood cell (RBC) as well as other cells and tissues. These antigens are of carbohydrate nature and their synthesis is catalysed by glycosyltransferases encoded by the ABO gene. Blood group O lack the A and B determinants as a result of inactivating mutations at the ABO locus and does not evoke an immunological response and often deemed “universal”.

During the ECO-project (Enzyme Conversion to Group O Red Blood Cells), group A and B RBCs were successfully converted to functional group O cells. This project also uncovered so called atypical ABO antigens; carbohydrate structures related to, but not identical to the A and B antigens.

My primary focus is to attempt to characterise these antigens by determining their genetic back ground, biochemical structure and identify which glycosyltransferases involved in their synthesis.