Dissociation of ABH antigen expression from von Willebrand factor synthesis in endothelial cell lines.

ABO blood group determines plasma von Willebrand factor (VWF) levels and ABH antigens are present on VWF. To investigate whether ABO influences the rate of VWF synthesis, we performed stable transfection of A transferase in a phenotypically group-O endothelial cell line (EAhy926). A transferase expression did not affect the rate of VWF synthesis. Although high levels of A antigen were expressed on the cell surface, no A determinants were added to VWF synthesized within these cells. Further studies demonstrated H structures were not present on EAhy926-derived VWF, despite the fact that H antigen is constitutively expressed by these cells.