Anticoagulant response of plasma to APC:protein S is enhanced by addition of GlcCer and Gb3Cer.

Glycolipids were added to normal plasma aliquots, which were then assayed using the dilute modified PT assay as described21in the presence and absence of APC:protein S. Clotting times are shown for the presence of APC:protein S (● indicates GlcCer; ▵, Gb3Cer; ■, GalCer; and ▿, LacCer) and for baseline controls (without APC or protein S added) (○ indicates GlcCer; ▴, Gb3Cer; ▪, GalCer; and ▾, LacCer). For GlcCer addition, clotting times are also shown for addition of APC alone (♦ indicates GlcCer).