Study on temporal osteopontin expression and its influence on matrix mineralization of osteogenic cells cultured on a nanotextured titanium surface

• Grant number: 10/15414-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2011
• End date: May 31, 2012
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Paulo Tambasco de Oliveira
• Grantee: Adriel Henrique Peixoto da Silva Geraldo
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

It has been demonstrated that nanotextured titanium-based surfaces enhance both cytoplasmic and extracellular osteopontin (OPN) immunoreactivity and accelerate and/or enhance bone-like nodule formation in osteogenic cells cultures. The present study is a step further, aiming at verifying whether the more intense OPN immunolabeling in cultures grown on nanotopography correlates with mRNA and protein levels. In addition, the impact of OPN expression on the matrix mineralization process will also be evaluated using siRNA strategy. Cells will be obtained by enzymatic digestion of newborn rat calvaria and grown on titanium discs with nanotextured or machined, control surfaces. At days 4, 7 and 10, the following parameters will be evaluated: 1) OPN mRNA expression by Real Time PCR, 2) quantification of OPN protein levels by ELISA, and 3) immunolocalization of OPN by indirect immunofluorescence. The silencing of OPN will be performed at 6 hours post-plating and its effect on matrix mineralization will be qualitatively and quantitatively evaluated at days 10 and 14.