Subcellular distribution of WT and mutant rVWF. HEK293 cells were transiently transfected with either WT rVWF (A-C); rVWF-Cys1225Gly (D-F); rVWF-Cys788Arg (G-I); or rVWF-Arg273Trp (J-L), and were coimmunolabeled for VWF and the endoplasmic reticulum marker calreticulin. In panels A, D, G, and J, VWF exhibits ER staining only (in yellow); in panels B, E, H, and K, VWF exhibits ER (in yellow) and pseudo-WPB staining (in red; arrowheads); in panels C, F, I, and L, VWF exhibits pseudo-WPB staining only (in red; arrowheads). Bar is 20 μm.