预期应用
ELISA法定量测定猪血清、血浆或其它相关液体中VWF含量。
产品介绍
Von Willebrand Factor因子是一多聚糖蛋白，它与凝血因子VIII以非共价方式结合成复合物存在于血浆中。正常的止血过程中，高分子量多聚体形式的vWF可作为分子桥介导血小板球蛋白IB与内皮下胶原的黏附反应。先天性VWF异常可引起中度至重度出血倾向—此为Von Willebrand病（VWD）。
实验原理
本试剂盒应用双抗体夹心酶标免疫分析法测定标本中vWF水平。用纯化的抗体包被微孔板，制成固相抗体，往包被单抗的微孔中依次加入vWF抗原、生物素化的抗vWF抗体、HRP标记的亲和素，经过彻底洗涤后用底物TMB显色。TMB在过氧化物酶的催化下转化成蓝色，并在酸的作用下转化成最终的黄色。颜色的深浅和样品中的vWF呈正相关。用酶标仪在450nm波长下测定吸光度（OD值），计算样品浓度。
Intended use
This immunoassay kit allows for the specific measurement of Porcine Von Willebrand Factor （vWF）concentrations in cell culture supernates, serum, and plasma.
Introduction
Von Willebrand factor is a blood glycoprotein involved in coagulation. It is deficient or defective in von Willebrand disease and is involved in a large number of other diseases, including thrombotic thrombocytopenic purpura, Heydes syndrome, and possibly hemolytic-uremic syndrome.vWF is a large multimeric glycoprotein present in blood plasma and produced constitutively in endothelium (in the Weibel-Palade bodies), megakaryocytes (α-granules of platelets), and subendothelial connective tissue.The basic vWF monomer is a 2050 amino acid protein. Von Willebrand factor is not an enzyme and therefore has no catalytic activity. Its primary function is binding to other proteins, particularly Factor VIII and it is important in platelet adhesion to wound sites.
vWF binds to a number of cells and molecules. The most important ones are:
Factor VIII is bound to vWF whilst inactive in circulation;
vWF binds to collagen, e.g., when it is exposed in endothelial cells due to damage occurring to the blood vessel.
vWF binds to platelet gpIb when it forms a complex with gpIX and gpV; this binding occurs under all circumstances, but is most efficient under high shear stress.
vWF binds to other platelet receptors when they are activated, e.g., by thrombin (i.e., when coagulation has been stimulated).
vWF appears to play a major role blood coagulation, and vWF deficiency or dysfunction (von Willebrand disease) therefore leads to a bleeding tendency, which is most apparent in tissues having high blood flow shear in narrow vessels. From studies it appears that vWF uncoils under these circumstances, decelerating passing platelets.
Test principle
This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal
antibody specific for VWF has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any VWF present is bound by the immobilized antibody. An
enzyme-linked monoclonal antibody specific for VWF is added to the wells. Following a wash to remove any unbound antibody-enzyme reagent, a substrate solution is added to the wells
and color develops in proportion to the amount of VWF bound in the initial step. The color
development is stopped and the intensity of the color is measured.
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