[Effect of tissue factor pathway inhibitor on the adhesion of platelet onto polyethylene and polyvinylchloride...

Tissue factor pathway inhibitor(TFPI) is the major inhibitor of the extrinsic pathway of the blood coagulation cascade. Our previous study showed that TFPI could obviously prolong the blood coagulation time on the surface of polyethelene(PE) and polyvinylchloride(PVC) membranes in vitro and decrease the generation of thrombus on Dacron membrane in vivo. In the present study, the effect of TFPI on the adhesion of platelet onto PE and PVC membranes was investigated. PE or PVC membrane was cut into small pieces and incubated in 96-well culture plate with GST or GST-TFPI fusion protein at 4 degrees C over night. Freshly collected rabbit blood was mixed with 3.8% sodium citrate. Platelet-rich plasma was separated by centrifugation and then incubated with the treated membranes at 37 degrees C for 30 minutes. The membranes were then washed, fixed, and freeze-dehydrated Adhesion of platelet was observed through scanning electronic microscope. The result showed that GST-TFPI treatment significantly decreased the number of platelet adhered on the membrane when compared with the GST and control group, and it suggested that TFPI might have a great potential to be used as an anticoagulant for improving the hemocompatibility of biomaterials.