Biofunctionalization of PLDLA scaffolds immobilized with cyclic RGDfK peptide and knuckle epitope (73-92) of BMP-2

Author(s)

Bruna Antunes Más

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Mecânica
• Defense date: 2016-01-29

Examining board members

Eliana Aparecida de Rezende Duek; Marcos Akira D'Avila; Cecília Amélia de Carvalho Zavaglia; Arnaldo Rodrigues dos Santos Junior; Sônia Maria Malmonge

• Advisor: Eliana Aparecida de Rezende Duek

Abstract

The biofunctionalization of bioresorbable polymeric scaffolds by chemical immobilization of bioactive peptides capable of being naturally recognized by the native bone tissue and then, stimulate osteogenic differentiation of mesenchymal stem cells (MSCs), is a promising strategy in bone tissue engineering field. In the present study, the surface of poly (L-co-D,L lactic acid) ¿ PLDLA was biofunctionalized with the cyclic RGDfK peptide and peptide derived from the knuckle epitope of BMP-2 (73-92), which are mainly involved in cell adhesion and regulation of bone maturation. The immobilization of peptides was obtained through the pre-activation of PLDLA surface using oxygen plasma treatment, followed by the covalent immobilization of peptides via EDC / sulfo-NHS reaction. The results obtained by X-ray photoelectron spectroscopy (XPS) and attenuated total re?ectance infrared spectroscopy (ATR-FTIR) techniques confirmed the immobilization of peptides which establishes bond efficiency in a 1: 2 ratio with predominance of BMP-2 on cRGDfK peptide, also confirmed by confocal laser microscopy (CLM). The oxygen plasma treatment under power condition of 100W resulted in a significant decrease in molecular weight which is indicative of degradation; however, the mechanical properties of biofunctionalized scaffolds were not affected. Biological evaluation of biofunctionalized scaffolds with the peptides cRGDfK, BMP-2 and cRGDfK / BMP-2 demonstrated that the association of the peptides exerts synergistic effect on adhesion and osteogenic differentiation of Wistar rats bone marrow derived mesenchymal stem cells (MSCs), which was confirmed by a higher level of alkaline phosphatase and collagen production found after 7 days of culture. These results indicate that the surface modification method in the present study can be used in the development of bioactive and biomimetic scaffolds with potential application in bone tissue engineering and regenerative medicine (AU)

• FAPESP's process: 12/22593-0 - Biofunctionalization of PLDLA scaffolds immobilized with RGD peptide and bone morphogenetic protein BMP-2
• Grantee: Bruna Antunes Más
• Support Opportunities: Scholarships in Brazil - Doctorate