Fibronectin silanized titanium alloy: A bioinductive and durable coating to enhance fibroblast attachment in vitro

Abstract

Long term success of percutaneous implants is dependent on soft tissue attachment to prevent infection and epithelial downgrowth, which leads to failure of the implant. Fibronectin coatings are known to enhance fibroblast attachment in vitro, but are subject to desorption from serum protein competition in vivo. This paper quantifies the binding of fibronectin to titanium alloy by silanization and the durability of this attachment when soaked in protein-rich fluid compared with adsorbed fibronectin. The biological activity of fibronectin bound to silanized titanium alloy was confirmed by analyzing cell area, morphology, immunolocalization of focal contacts, and metabolism of dermal fibroblasts. This was compared with both adsorbed fibronectin and uncoated titanium alloy. Silanized titanium alloy bound over twice the amount of fibronectin compared to untreated titanium alloy. On soaking in fetal calf serum there was no significant loss of fibronectin (p = 0.589) from the silanized surface but a significant 44% loss (p = 0.002) from untreated surfaces. Fibroblasts on silanized fibronectin had significantly larger cell areas and more vinculin focal contact markers when compared to untreated surfaces (p < 0.005). The results confirm the durability of silanized fibronectin from protein competition and bioactive effect on fibroblasts.

Biofunctionalized anti-corrosive silane coatings for magnesium alloys

“…Functional silanes, such as γ-APS, have often been used for modification of stainless steel [33] and Ti [30,34] to provide surface functionality for post chemical anchorage of biomolecules (e.g. collagen, heparin and fibronectin), with a view to improving the biocompatibility of these metallic implants.…”

Effects of Ti surface treatments with silane and arginylglycylaspartic acid peptide on bone cell progenitors

“…Previous studies have indicated that silane treatment on various substrate surfaces, such as gold, platinum, Ti, and glass, can promote cell adhesion and proliferation [11] and enhance the adhesive ability of cells [9]. Silanization involves binding silane to substrate surfaces.…”

“…Titanium (Ti) surfaces are coated with a stable and bioinert titania oxide layer, and thus, researchers have used silane as the grafting bridge between Ti substrates and proteins through varied sequences to install various amino acids in a polypeptide chain to this type of surface [9][10][11]. Previous studies have indicated that silane treatment on various substrate surfaces, such as gold, platinum, Ti, and glass, can promote cell adhesion and proliferation [11] and enhance the adhesive ability of cells [9].…”

“…Silanization involves binding silane to substrate surfaces. After hydrolysis, 3-mercaptopropyl trimethoxysilane (MPTMS) yields a reticular structure and comprises two functional groups, Si-O-Si and -SH, allowing dissociated proteins in fluids to bind covalently with substrate surfaces [9].…”

Preventing infection of osseointegrated transcutaneous implants: Incorporation of silver into preconditioned fibronectin-functionalized hydroxyapatite coatings suppresses Staphylococcus aureus colonization while promoting viable fibroblast growth in vitro

“…1,3,4 Fibronectin is a glycoprotein that contains an arginine-glycine-aspartate (RGD) amino acid sequence that attaches cells via integrins and increases fibroblast adhesion. 18 Fibronectin may be adsorbed onto hydroxyapatite to further enhance the effects of hydroxyapatite on soft tissue attachment. 3,19,20 For example, Pendegrass et al implanted subcutaneous plates into sheep tibia and found that fibronectin-functionalized hydroxyapatite (HAFn) coatings were associated with greater dermal tissue ingrowth and attachment than nonfunctionalized hydroxyapatite coatings.…”