In vitro osteoinduction of human mesenchymal stem cells in biomimetic surface modified titanium alloy implants

Abstract

Interaction between cells and implant surface is crucial for clinical success. This interaction and the associated surface treatment are essential for achieving a fast osseointegration process. Several studies of different topographical or chemical surface modifications have been proposed previously in literature. The Biomimetic Advanced Surface (BAS) topography is a combination of a shot blasting and anodizing procedure. Macroroughness, microporosity of titanium oxide and Calcium/Phosphate ion deposition is obtained. Human mesenchymal stem cells (hMCSs) response in vitro to this treatment has been evaluated. The results obtained show an improved adhesion capacity and a higher proliferation rate when hMSCs are cultured on treated surfaces. This biomimetic modification of the titanium surface induces the expression of osteblastic differentiation markers (RUNX2 and Osteopontin) in the absence of any externally provided differentiation factor. As a main conclusion, our biomimetic surface modification could lead to a substantial improvement in osteoinduction in titanium alloy implants.

Trabecular titanium can inducein vitroosteogenic differentiation of human adipose derived stem cells without osteogenic factors

“…It has been previously demonstrated that in vivo porous titanium implants have different biological behaviors: increased porosity and pore size showed a direct positive effect on the amount of new bone growth . Biomimetic modified titanium surfaces were important to improve cell adhesion, proliferation and osteogenic differentiation in the absence of any differentiation molecule . In vitro experiments demonstrated that a combination of surface properties like microstructure and high energy increased osteoblast maturation of MSCs or progenitor cells via autocrine and paracrine regulation .…”

“…43 Biomimetic modified titanium surfaces were important to improve cell adhesion, proliferation and osteogenic differentiation in the absence of any differentiation molecule. 44 In vitro experiments demonstrated that a combination of surface properties like microstructure and high energy increased osteoblast maturation of MSCs or progenitor cells via autocrine and paracrine regulation. 45 The trabecular structure of the scaffold here used is the main factor of the osteogenic differentiation of hASCs in "in vitro" conditions: the addition of osteogenic factors does not improve both gene and protein expression of markers of differentiation of stem cells toward osteoblastic phenotype.…”

Engineered coatings for titanium implants to present ultra-low doses of BMP-7

“… 5 Previous studies to enhance the surface of Ti as an implant material were challenged by confounding factors. 4 These included physical characteristics (e.g., surface roughness) and multiple biologically active factors in the serum when the samples were tested in vitro . 4 , 6 …”

“… 4 These included physical characteristics (e.g., surface roughness) and multiple biologically active factors in the serum when the samples were tested in vitro . 4 , 6 …”

“…Among others, fibronectin (FN) is one of the soluble ECM proteins playing a critical role in osteogenic differentiation. 4 , 7 − 9 It was also found that crucial binding sites for many growth factors on the FN molecule become available when FN is unfolded. It is important to note that these sites are not available when the FN is in its globular conformation.…”