Impact of mutations in the von Willebrand factor A2 domain on ADAMTS 13-dependent proteolysis
Impact of mutations in the von Willebrand factor A2 domain on ADAMTS 13-dependent proteolysis
复制标题
DOI：
10.1182/blood-2005-04-1758
复制
发表时间：
2006-03-15
期刊：
影响因子：
20.3
通讯作者：
Schneppenheim, R
中科院分区：
文献类型：
--
作者：
Hassenpflug, WA;Budde, U;Schneppenheim, R
经典型血管性血友病（VWD）2A型是VWD最常见的质量缺陷，由血管性血友病因子（VWF）的高分子量多聚体（HMWMs）丢失引起。我们研究了2A型VWD患者中常见的突变对VWF的AIDAMTS13依赖性蛋白水解的影响。我们使用重组人ADAMTS13（rhuADAMTS13）消化重组全长VWF和跨越VWF A1至A3结构域的VWF片段，所述VWF片段具有13种不同的VWD 2A型突变（C1272S、G1505E、G1505R、S1506L、M1528V、R1569del、R1597W、V160713、G1609R、11628T、G11629E、G163113和E1638K）。除G1505 E和11628 T外，VWF A2结构域中的所有突变均增加了VWF的特异性蛋白水解，与表达水平无关。突变型VWF的体外蛋白水解敏感性与患者体内表型密切相关。结果表明，ADAMTS13的VWF易感性增加是经典VWD 2A型的组成特性，从而解释了在患者多聚体分析中观察到的显著蛋白水解片段和HMWM丢失。
Classical von Willebrand disease (VWD) type 2A, the most common qualitative defect of VWD, is caused by loss of highmolecular-weight multimers (HMWMs) of von Willebrand factor (VWF), Underlying mutations cluster in the A2 domain of VWF around its cleavage site for ADAMTS13. We investigated the impact of mutations commonly found in patients with VWD type 2A on AIDAMTS13-dependent proteolysis of VWF. We used recombinant human ADAMTS13 (rhuADAMTS13) to digest recombinant full-length VWF and a VWF fragment spanning the VWF A1 through A3 domains, harboring 13 different VWD type 2A mutations (C1272S, G1505E, G1505R, S1506L, M1528V, R1569del, R1597W, V160713, G1609R, 11628T, G11629E, G163113, and E1638K). With the exception of G1505E and 11628T, all mutations in the VWF A2 domain increased specific proteolysis of VWF independent of the expression level. Proteolytic susceptibility of mutant VWF in vitro closely correlated with the in vivo phenotype in patients. The results imply that increased VWF susceptibility for ADAMTS13 is a constitutive property of classical VWD type 2A, thus explaining the pronounced proteolytic fragments and loss of HMWM seen in multimer analysis in patients.