In vitro evaluation of platelet activation by tubular biomaterials / 中国组织工程研究

ABSTRACT

BACKGROUND: In according to ISO-10993-4 and GB/T 16886.4, the in vitro hemo-compatibility evaluation on biomaterieisincludes thrombosis, coagulation factors, platelets and platelet functions, hematology and complement system. However, in thecase of China, the in vitro hemo-compatibility evaluations were performed only thrombosis, coagulation factors and plateletattachment, the investigation on evaluation of platelet and complement activations is less reported.OBJECTIVE: To evaluate the effect of polyethylene, polyvinyl chloride and polymethylvinylsiloxane tubes on platelet activation,and establish a useful method to evaluate the effect of tubular materials on platelet activation.METHODS: Tubes of polyethylene, poiyvinyl chlorid and silastic were established by 3.7 mm inner diameter, 3.5 mm externaldiameter, and 35 cm length, respectively. 1 mL blood was injected into the tube of polyethylene, polyvinyl chlorid and silasUc,respectively. The tubes were connected using a two-way tube, shaken at 140 r/min by 30° sloping for 3.5 hours at 37 ℃.Radiolmmunoassay was employed to detect α-granules protein level of platelet poor plasma, while flow cytometry was used todetect the percentage of positive plateiet of o-granules protein and that of activated gp Ⅱb/Ⅲa composite.RESULTS AND CONCLUSION: Radiolmmunoassay showed that o-granules protein level of plateiet poor plasma in thepolyethylene and polyvinyl chlorid tubes was significantly greater than that in the silastic tube (P < 0.05). There were no significantdifferences in o-granules protein between polyethylene and polyvinyl chlorid (P > 0.05). Flow cytometry indicated that percentageof positive platelet of o-granules protein in the polyethylene and polyvinyl chlorid tubes was significantly greater than that in thesilastic tube (P < 0.05); the percentage in the polyethylene tube was significantly greater than that in the polyvinyl chlorid tube (P <0.05). There was no significant differences in the percentage of positive plateiet of activated gp IIb/IIIa composite between thethree materials (P > 0.05). A useful blood-material contact model was established, and it was considered that o-granules protein isan available parameter for evaluating platelet activation. The percentage of positive platelet of o-granules protein determined byflow cytometry was a more sensitive parameter for evaluating platelet activation.