von Willebrand factor propeptide to antigen ratio identifies platelet activation and reduced von Willebrand factor survival phenotype in mice

Abstract

Background Reduced plasma survival of von Willebrand factor (VWF) is characteristic of patients with type 1C von Willebrand disease (VWD). These subjects can be identified by an increased steady-state ratio of plasma VWF propeptide (VWFpp) to VWF antigen (VWF:Ag). A similar phenotype occurs in mice with the Mvwf1 allele. Objectives To (i) determine if the VWFpp/VWF:Ag ratio can be used to identify a 'type 1C' phenotype in mice, (ii) determine the most reliable method for murine blood sampling, and (iii) identify the source of VWF released during problematic blood collection. Methods 'Platelet-VWF' and 'endothelial-VWF' mice were generated by bone marrow transplantation between C57BL/6J and VWF-/- mice. Several blood sampling methods were used and murine VWFpp and VWF:Ag levels determined. Plasma and platelet VWF:Ag and VWFpp, VWF multimers and VWF half-life were examined in mouse strains with and without Mvwf1. Results A single retro-orbital bleed and vena cava collection were found to be the optimal methods of blood collection. Problematic collection resulted in release of VWF from platelets and endothelium. The VWFpp/VWF:Ag ratio identified strains of mice with reduced VWF survival. Conclusion Assay of murine VWFpp and VWF:Ag has utility in determining the acceptability of murine blood samples for coagulation testing and in identification of a reduced VWF survival phenotype in mice.

Studying the variations in differently expressed serum proteins of Hainan black goat during the breeding cycle using isobaric tags for relative and absolute quantitation (iTRAQ) technology

“…vWF is a polysaccharide protein secreted by endothelial cells and megakaryocytes that plays an important role in hemostasis. It can combine with collagen fibers to promote blood platelet adhesion to the injured part; it can also combine with factor VIII to protect it from hydrolysis by proteases [27, 28]. A study [29] has shown that the expression level of vWF is associated with bacterial translocation, inflammation, and procoagulant imbalance.…”

Methods for diagnosing endothelial dysfunction

“…В нормальной плазме человека соотношение vWFpp/ vWF:Ag составляет 1,0. У пациентов с болезнью Виллебранда типа 1С наблюдают снижение концентрации vWF из-за его быстрого выведения, что вызывает увеличение данного соотношения [33,39].…”

Bleeding diathesis in mice lacking JAK2 in platelets

“…Mouse blood was collected by cardiac puncture and anticoagulated in citrate. 25 The plasma Von Willebrand factor (VWF) level was determined by antigen capture enzyme-linked immunosorbent assay with monoclonal anti-mouse VWF antibody 344.3 (Versiti) for capture and biotinylated polyclonal anti-VWF (DAKO) for detection. The VWF propeptide (VWFpp) level was determined by antigen capture enzyme-linked immunosorbent assay, with monoclonal anti-VWFpp antibody 349.3 (Versiti) used for capture and biotinylated monoclonal anti-VWFpp antibody 349.2 (Versiti) for detection.…”