Surface modification of biomaterials using advanced peptide engineering

초록

Tissue engineering is dependent on the use of biocompatible polymer scaffolds. Synthetic biodegradable polymers are now widely used in tissue engineering due to their generally good strength and adjustable degradation time. However, the biologically inert polymeric scaffolds are unlikely to induce cell adhesion and tissue formation. One approach to overcome this drawback of polymeric scaffolds is to modify surface of polymer with extracellular matrix (ECM) proteins. An ideal ECM-mimetic tissue engineering scaffold should contain both adhesion proteins and growth factors. Fibroblast growth factor 2 (FGF-2) belongs to the fibroblast growth factor family and is one of the most potent growth factors regulating cellular functions including cell proliferation, motility, differentiation, and survival, and also plays an important role in tissue regeneration processes in vivo, i.e., embryonic development, angiogenesis, osteogenesis, chondrogenesis, and wound repair. FGF-2 is currently available as a pharmaceutical medicine. We have previously reported the synergistic effect of fibronectin and fibroblast growth factor 2 (FGF-2) on osteoblast cell adhesion through extracellular signal-regulated kinase (ERK) pathway. Here we describe the engineering of a fusion protein containing fibronectin fragment (FNIII9-10) connected to the COOH-terminus of FGF-2. Purified FGF2-FNIII9-10 fusion protein exhibited significant increase of cell adhesion and proliferation of MG63 cells compared with FNIII9-10 alone (p<0.05). Biomimetic approach to modify the surface of Ti can improve its osseointegration through the incorporation of biomolecules to mediate the molecular and cellular response to the Ti. Here, we evaluated the engineered biomimetic surface of Ti by using recombinant fragment of fibronectin and vitronectin that contains the binding site for integrins.