Evaluation of protein concentration VEGF and PDGF stored in alpha granules of paltelet donor blood

• Grant number: 11/23143-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2012
• End date: August 31, 2012
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Estela Maria Novak
• Grantee: Michelle Karina da Silva
• Host Institution: Hemocentro de São Paulo. Fundação Pró-Sangue. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Platelets are a source of several growth factors, with great therapeutic potential. Once released from alpha granules of activated platelets, these factors will act in the injury site, stimulating chemotaxis and angiogenesis, thereby improving tissue repair. However, several studies show a difference between the concentrations of growth factors (CF) VEGF (vascular endothelial growth factor), and PDGF (Platelet-derived growth factor) in platelets and in the different systems of preparation and storage. In addition to PDGF, the decrease of VEGF can also affect the prophylaxis of serious bleeding. On the other hand, despite the growth factors found in the alpha granules being essential for the normal activity of platelets, platelets are capable of sequestering angiogenic proteins produced by tumor cells, and storing them in the alpha granules. Angiogenesis is critical both in normal wound healing, and in tumor growth. In both situations, the development of new blood vessels is stimulated by various growth factors such as PDGF and VEGF, which may be released from alpha granules. It is important to note that the interaction between circulating platelets and tumor cells can influence tumor growth and spread. Patients receiving platelet concentrates from whole blood or apheresis may be the accumulation of angiogenic proteins. This study proposes to verify in platelet concentrates obtained from whole blood and apheresis donor blood bank FPS / HSP, if there is any change in the number of factors PDGF and VEGF stored in alpha granules in 1, 3, and 5 days after the preparations.(AU)