Tripodi A, Arbini A, Chantarangkul V, Mannucci P M
A. Bianchi Bonomi Hemophilia and Thrombosis Center, IRCCS Maggiore Hospital and University, Milano, Italy.
Thromb Haemost. 1992 Jan 23;67(1):42-5.
Relipidated recombinant tissue factor (r-TF) has been assessed in comparison with conventional rabbit brain thromboplastin (Manchester Reagent) for its suitability for measurement of prothrombin time (PT). The International Sensitivity Index (ISI) of r-TF calibrated against the International Reference Preparation BCT/253 (human plain) was found to be 0.96 and 1.12 with instrumental and manual techniques. Our study of plasmas from patients with congenital deficiencies of clotting factors covering a wide range of severity demonstrates that r-TF is able to detect even minor deficiencies of factors involved in the extrinsic and common coagulation pathways. Patients with liver diseases were correctly diagnosed with a prevalence of abnormal results comparable for both reagents. Between-assay reproducibility expressed as coefficient of variation was 2.3% and 3.9% at normal and abnormal PT levels. In conclusion, our evaluation shows that relipidated r-TF possesses the necessary requisites of sensitivity, diagnostic accuracy and reproducibility which make it a suitable candidate for PT determination both for monitoring oral anticoagulant therapy and diagnosing congenital and acquired clotting factor deficiencies. Moreover, being a highly defined reagent it may constitute a step forward in the standardization of PT testing.
已对重新脂质化的重组组织因子（r-TF）与传统兔脑凝血活酶（曼彻斯特试剂）在测定凝血酶原时间（PT）方面的适用性进行了评估。以国际参考制剂BCT/253（人血浆）校准的r-TF的国际敏感指数（ISI），采用仪器法和手工法分别为0.96和1.12。我们对患有先天性凝血因子缺乏症且严重程度范围广泛的患者血浆进行的研究表明，r-TF甚至能够检测到外源性和共同凝血途径中相关因子的轻微缺乏。两种试剂对肝病患者的诊断正确率相当，异常结果的发生率相近。以变异系数表示的批间重复性在正常和异常PT水平分别为2.3%和3.9%。总之，我们的评估表明，重新脂质化的r-TF具备敏感性、诊断准确性和可重复性等必要条件，使其成为监测口服抗凝治疗以及诊断先天性和获得性凝血因子缺乏症时PT测定的合适候选物。此外，作为一种高度明确的试剂，它可能在PT检测标准化方面向前迈出了一步。
