Abo blood system influence on the Von Willebrand factor and pro-peptide VWF: AGII

• Grant number: 15/11815-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2015
• End date: June 30, 2016
• Field of knowledge: Biological Sciences - Biochemistry - Chemistry of Macromolecules
• Principal Investigator: Rosangela de Paula Silva Soares
• Grantee: Daniela Flosi Valadares
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Von Willebrand factor (VWF) is a protein involved in homeostasis, responsible for mediating platelet adhesion and aggregation at sites of vascular injury. This protein is synthesized as pre-pro-VWF and contains a signal peptide, a propeptide known as VWF:AgII and a mature subunit. The mature subunit and the propeptide are secreted in equimolar amounts, though with different half-lives. Additionally, plasmatic concentrations of VWF are influenced by numerous factors, including the ABO blood group system. This influence is justified by the fact that ABO carbohydrates are also found in the N-terminal region of VWF´s oligosaccharide chains. The propeptide however, appears not to be influenced by the ABO blood system. Therefore, we intend to determine the concentrations of VWF and VWF:AgII in healthy subjects, using the ELISA method, in order to propose the VWF:AgII as a more reliable marker for endothelial cell lesions than the mature VWF. This study will be conducted at the Faculty of Medicine´s Clinical Hospital, at the University of São Paulo, and will be made up of an average of 120 donors, separated by blood type, gender and age in order to study the association between ABO blood group and its interference in the plasmatic concentrations of VWF:Ag and VWF:AgII in a healthy population.