Immobilized Enzymes for ABO-Independent Blood Cell Transfusions

The transfusion of blood products requires ABO compatibility due to A and B antigens on blood cells and their corresponding antibodies in plasma. The supply of red cell concentrates (RCCs) and platelet concentrates (PCs) is challenged by rising demand and declining numbers of donors. To counteract the supply limitations, a method is developed to generate universal RCCs and PCs. For this, the A antigen is enzymatically removed by two enzymes from Flavonifractor plautii working in concert and the B antigen is removed by galactosidases from Pedobacter panaciterrae (PpaGal_WT or the variant PpaGal_W260Y) and Akkermansia muciniphila (AmGH110A or AmGH110B). The glycosidases are immobilized on polymethacrylate microparticles and are removed by the 200 µm filter of the mandatory transfusion set before the transfusion to avoid a possible immune reaction by the enzymes. B-positive red cells in RCCs are reduced below a 4% background signal within 48 h at 2-6 °C. Pooled PCs showed a 34 ± 14% reduction in B-positive cells and a residual A-positive platelet population of 4 ± 1% after 4 h of treatment at 20-24 °C. This approach efficiently generates ABO-universal RCCs and PCs while preserving blood quality and reducing incompatibility risks.