Expression of ADAMTS13 containing single point mutations. Conditioned medium (A) and cell lysate (B) of transfected HEK 293 cells expressing single mutant ADAMTS13 variants (abbreviations correspond to Figure 1) were normalized according to β-gal activity and analyzed by immunoblotting using an antibody against ADAMTS13 catalytic domain. The representative of at least 3 repetitive experiments is shown.