Brown S A, Eldridge A, Collins P W, Bowen D J
Katharine Dormandy Haemophilia & Haemostasis Unit, Royal Free Hospital, London, UK.
J Thromb Haemost. 2003 Aug;1(8):1714-7. doi: 10.1046/j.1538-7836.2003.00359.x.
The mechanism of von Willebrand factor (VWF) clearance is not fully understood. The factors that affect VWF clearance, and the normal in vivo mechanism of clearance, may be relevant to the pathogenesis of Type 1 von Willebrand disease (VWD), in which there is a partial deficiency of VWF. In order to investigate the clearance of VWF in Type 1 VWD, the current study assessed the half-life of VWF antigen (t(1/2) VWF:Ag) in Type 1 VWD patients and individuals with mild hemophilia A following the administration of 1-deamino-8-d-arginine vasopressin (DDAVP; desmopressin). To date 20 individuals have been assessed, 13 with Type 1 VWD and seven with mild hemophilia A. The median t(1/2) VWF:Ag in the Type 1 VWD and mild hemophilia A groups were 4.6 h and 9.5 h, respectively. The difference between the t(1/2) VWF:Ag for the two groups was significant, P < 0.02. Analysis of the data showed a correlation between the t(1/2) VWF:Ag and the baseline VWF:Ag level prior to administration of DDAVP: lower baseline VWF:Ag levels were associated with a shorter t(1/2) VWF:Ag. These data suggest that increased clearance of VWF may be the pathogenic mechanism in some cases of Type 1 VWD.
血管性血友病因子（VWF）清除的机制尚未完全明确。影响VWF清除的因素以及体内正常的清除机制，可能与1型血管性血友病（VWD）的发病机制相关，1型VWD存在VWF部分缺乏的情况。为了研究1型VWD中VWF的清除情况，本研究评估了1型VWD患者和轻度A型血友病个体在给予1-去氨基-8-D-精氨酸加压素（DDAVP；去氨加压素）后VWF抗原的半衰期（t(1/2) VWF:Ag）。迄今为止，已评估了20名个体，其中13名患有1型VWD，7名患有轻度A型血友病。1型VWD组和轻度A型血友病组的t(1/2) VWF:Ag中位数分别为4.6小时和9.5小时。两组的t(1/2) VWF:Ag差异显著，P < 0.02。数据分析显示，t(1/2) VWF:Ag与给予DDAVP前的基线VWF:Ag水平之间存在相关性：较低的基线VWF:Ag水平与较短的t(1/2) VWF:Ag相关。这些数据表明，VWF清除增加可能是某些1型VWD病例的发病机制。
