Synergistic Effect of Titanium Alloy and Collagen Type I on Cell Adhesion, Proliferation and Differentiation of Osteoblast-Like Cells

Abstract

A number of studies have demonstrated the pivotal role of collagen in modulating cell growth and differentiation. In bone, where the extracellular matrix is composed of approximately 85% type I collagen, cellular interaction with matrix components has been shown to be important in the regulation of the osteoblast phenotype. Preservation or enhancement of normal osteoblast function and appositional bone formation after implant placement represents a strategy that can be useful for the purpose of improving osseointegration. In order to further improve biocompatibility, we combined two known favorable compounds, namely the titanium alloy, Ti6A14V, with type I collagen. We assessed the in vitro behavior of primary osteoblasts grown on both fibrillar collagen-coated and tropocollagen-coated Ti6A14V in comparison with uncoated titanium alloy, using an improved adsorption procedure. As parameters of biocompatibility, a variety of processes, including cell attachment, spreading, cytoskeletal organization, focal contact formation, proliferation and expression of a differentiated phenotype, were investigated. Our results demonstrated for the first time that in comparison to uncoated titanium alloy, collagen-coated alloy enhanced spreading and resulted in a more rapid formation of focal adhesions and their associated stress fibers. Growing on collagen-coated Ti6A14V, osteoblasts had a higher proliferative capacity and the intracellular expression of osteopontin was upregulated compared to uncoated titanium alloy. Type I collagen-coated titanium alloy exhibits favorable effects on the initial adhesion and growth activities of osteoblasts, which is encouraging for its potential use as bone graft material. Moreover, collagen type I may serve as an excellent biocompatible carrier for osteotropic factors such as cell adhesion molecules (e.g. fibronectin) or bone-specific growth factors.

Tissue Response of Surface-Modified Three-Dimensional Titanium Fiber Structure

“…Collagen and fibronectin are well-known cell adhesion proteins, which have RGD moieties, and their effectiveness for immobilization onto titanium for cell responses such as cell activity, initial cell attachment or cell spreading have been reported. 40,41) The present study showed that collagen or fibronectin immobilization was not effective for external bone augmentation, but was for internal bone augmentation. For external bone augmentation, large quantities of formed blood vessels and connective tissue could be seen.…”

Design of Nano- and Microfiber Combined Scaffolds by Electrospinning of Collagen onto Starch-Based Fiber Meshes: A Man-Made Equivalent of Natural Extracellular Matrix

“…35,36 It has been used to coat metallic implant to enhance osteoblast spreading that results in a more rapid formation of focal adhesions and their associated stress fibers. 37,38 Our results suggest that the presence of type I collagen nanofibers appears to influence the cell viability of the osteoblast-like cells cultured on the developed structures. Besides the chemical influence of collagen, the previously deposited nanofibers reduce large void spaces between microfibers and create larger surface area that the cells can adhere from the very beginning.…”

Gene Expression of MC3T3-E1 Cells on Fibronectin-immobilized Titanium Using Tresyl Chloride Activation Technique

“…It is widely accepted that these adsorbed proteins control the subsequent biological responses at the implant-tissue interface. Some studies have reported that preadsorption on the titanium surface with cell-adhesive proteins, such as fibronectin, collagen, and laminin, improved cell activity, initial cell attachment, or cell spreading [4][5][6][7][8] .…”