Detection of sEPCR in plasma of A3-carrying subjects. Western blot of 2 JRK-1496 column elution fractions, each corresponding to the plasma EPCR forms contained in 2.5 mL of a pool of plasma from A3-carrying subjects (lanes 1 and 2) and of 2 JRK-1496 column elution fractions each corresponding to the plasma EPCR forms contained in 5 mL of pooled plasma from A3-noncarrying subjects (lanes 3 and 4) The 2 lanes on the left were loaded with recombinant rEPCRsol and rEPCRisoform, respectively, used as controls. The membrane were blocked, treated with goat anti-EPCR biotinylated antibody, washed, and then incubated with HRP-conjugated streptavidin. Bands were visualized with enhanced chemiluminescence (Pierce Chemical, Rockford, IL). Vertical lines have been inserted to indicate repositioned gel lanes, and the arrows point to the plasma EPCR isoform.