Turner N, Nolasco L, Tao Z, Dong J-F, Moake J
Department of Bioengineering, Rice University, Houston, TX 77005, USA.
J Thromb Haemost. 2006 Jun;4(6):1396-404. doi: 10.1111/j.1538-7836.2006.01959.x.
Hepatic stellate cells have been considered to be a primary source for human plasma ADAMTS-13, the von Willebrand factor (VWF)-cleaving metalloprotease. In this study, ADAMTS-13 antigen was detected by immunofluorescence in both venous (HUVECs) and arterial endothelial cells (HUAECs) using both polyclonal antibodies made against peptides found in various domains of human ADAMTS-13, as well as by a monoclonal antibody against the ADAMTS-13 metalloprotease domain. ADAMTS-13 antigen had an intra-cellular distribution in endothelial cells distinct from the Weibel-Palade body location of VWF, and was released from the cells during 48 h in culture. The mRNA for ADAMTS13 was detected in HUVECs and HUAECs using reverse transcription-polymerase chain reaction (RT-PCR), indicating that the enzyme is synthesized in these cells. The ADAMTS-13 protein was immunoprecipitated from HUVECs and had an approximate M(r) of 170 kDa, similar to the molecular mass of recombinant ADAMTS-13. The ADAMTS-13 in HUVEC and HUAEC lysates had enzymatic activity using both static and flow assays. We conclude that ADAMTS-13 is synthesized in human endothelial cells, and released constitutively. The vast number of endothelial cells in the body may be an important source of ADAMTS-13.
肝星状细胞被认为是人类血浆中血管性血友病因子裂解金属蛋白酶ADAMTS - 13的主要来源。在本研究中，使用针对人类ADAMTS - 13不同结构域中发现的肽段制备的多克隆抗体以及针对ADAMTS - 13金属蛋白酶结构域的单克隆抗体，通过免疫荧光法在静脉内皮细胞（HUVECs）和动脉内皮细胞（HUAECs）中检测到了ADAMTS - 13抗原。ADAMTS - 13抗原在内皮细胞中的细胞内分布与血管性血友病因子（VWF）的魏尔-帕拉德小体位置不同，并且在培养48小时期间从细胞中释放出来。使用逆转录-聚合酶链反应（RT-PCR）在HUVECs和HUAECs中检测到了ADAMTS13的mRNA，表明该酶在这些细胞中合成。从HUVECs中免疫沉淀出的ADAMTS - 13蛋白的近似分子量为170 kDa，与重组ADAMTS - 13的分子量相似。使用静态和流动分析方法，HUVEC和HUAEC裂解物中的ADAMTS - 13具有酶活性。我们得出结论，ADAMTS - 13在人内皮细胞中合成并组成性释放。体内大量的内皮细胞可能是ADAMTS - 13的重要来源。
