Hellstern P, Beeck H, Fellhauer A, Fischer A, Faller-Stöckl B
Institut für Transfusionsmedizin und Immunhämatologie, Klinikum der Stadt Ludwigshafen, Deutschland, Germany.
Vox Sang. 1997;73(3):155-61. doi: 10.1046/j.1423-0410.1997.7330155.x.
The aim of this study was to determine the potencies of factor VII (FVII) and of activated FVII (FVIIa) in prothrombin complex concentrates (PCC).
We examined 56 lots of PCC from 5 manufacturers. Three brands were licensed preparations, and 1 product series had been involved in thromboembolic complications. FVII and FVIIa were measured using a two-stage amidolytic assay and a specific clotting assay, respectively. We also quantified FVII clotting activity by a one-stage assay reflecting a mixture of FVII zymogen and FVIIa.
All PCC contained substantial amounts of FVII, and FVIIa could be detected in all lots. There were marked differences between manufacturers and some significant variabilities between batches. The two lots involved in thromboembolic events contained considerably more FVIIa than the PCC still licensed. The lowest FVIIa potencies were observed in an experimental product series, indicating that PCC can be produced without activation of FVII during the manufacturing process.
FVIIa is present in all PCC containing FVII. High FVIIa potencies may contribute to the thrombogenic potential of these preparations, and determination of FVIIa potencies should be included in the in vitro characterization of PCC.
本研究旨在测定凝血酶原复合物浓缩剂（PCC）中因子VII（FVII）和活化因子VII（FVIIa）的效价。
我们检测了来自5家制造商的56批PCC。3个品牌为许可制剂，1个产品系列曾出现血栓栓塞并发症。分别使用两阶段酰胺水解法和特异性凝血法测定FVII和FVIIa。我们还通过反映FVII酶原和FVIIa混合物的单阶段测定法对FVII凝血活性进行了定量。
所有PCC均含有大量FVII，且所有批次均能检测到FVIIa。不同制造商之间存在显著差异，不同批次之间也存在一些显著变异性。涉及血栓栓塞事件的两批产品所含FVIIa比仍获许可的PCC多得多。在一个实验产品系列中观察到最低的FVIIa效价，这表明在制造过程中可以在不激活FVII的情况下生产PCC。
所有含FVII的PCC中均存在FVIIa。高FVIIa效价可能导致这些制剂的血栓形成潜力，FVIIa效价的测定应纳入PCC的体外特性鉴定中。
