von Willebrand因子裂解酶活性水平的检测及其临床应用

Residual Collagen Binding Assay for von Willebrand Factor Cleaving Protease Activity and Its Clinical Application

血管性血友病因子裂解酶 (vWF cp)是新近发现的一个金属蛋白酶 ,其活性在多种生理病理状态下发生改变。为了研究vonWillebrand因子裂解酶活性检测及其临床应用 ,用ELISA法检测了vWF cp酶解前及裂解后血清 (浆 )中血管性血友病因子 (vWF)的胶原结合能力 ,两者之比作为该待测血清 (浆 )的相对vWF cp活性水平。同时观察血栓性血小板减少性紫癜 (TTP)患者与肿瘤患者体内vWF cp活性的改变。结果表明 ,该方法准确测出了87名健康成人和 79例患者血样的残余胶原结合力 (R CBA) ,批内变异和批间变异分别为 3.6 0 % (n =9)和 8.35 %(n =5 )。 5 3名健康成人血清vWF cp活性水平为 (79.4 7± 10 .78) % ,30名健康成人血浆vWF -cp活性水平为(78.79± 9.17) %。 6例TTP患者中 5例血浆vWF cp活性水平显著降低 ,2 5例良性肿瘤患者血清vWF cp水平轻度降低 ,4 9例恶性肿瘤患者则明显下降 (P值分别小于 0 .0 0 1,0 .0 3和 0 .0 0 1)。结论 :以R CBA检测vWF cp活性水平简单易行 ,可应用于临床检验。恶性肿瘤患者 ,尤其是TTP患者血浆 (清 )vWF cp活性水平显著降低。

von Willebrand factor cleaving protease (vWF cp) is a newly identified metalloproteinase. The activity of vWF cp would vary in different physiological or pathological states. To explore activity detectron of von Willebrand factor cleaving protease and its clinical application, the vWF cp activity was measured by a sensitive enzyme linked immunoadsorbent assay to detect the residual collagen binding activity (R CBA) of von Willebrand factor before and after digestion with vWF cp. Moreover, its activity deficiency in patients with thrombotic thrombocytopenic purpura (TTP) and solid tumors was also investigated. The results showed that the residual collagen binding assay was sensitive enough to measure the serum or plasma vWF cp activity in 87 health individuals, 79 patients suffering from TTP and solid tumors. The coefficient of variation within and between the batches was were 3.60% and 8.35%, respectively. The serum and plasma vWF cp activity in health individuals was (79.47±10.78)% (n=53) and (78.79±9.17)% (n=30), respectively, whereas the vWF cp activity in patients with TTP, benign and malignant tumors was significantly decreased (P values were less than 0.001, 0.03 and 0.001, respectively). It is concluded that the vWF cp activity in plasma or serum of patients with TTP and solid tumors markedly decrease, especially in patients with TTP. Assay of the vWF cp activity using R CBA is a simple method.