Mineralization of SaOS‐2 cells on enzymatically (silicatein) modified bioactive osteoblast‐stimulating surfaces

Abstract

There is a demand for novel bioactive supports in surgery, orthopedics, and tissue engineering. The availability of recombinant silica-synthesizing enzyme (silicatein) opens new possibilities for the synthesis of silica-containing bioactive surfaces under ambient conditions that do not damage biomolecules like proteins. Here it is shown that growth of human osteosarcoma SaOS-2 cells on cluster plates precoated with Type 1 collagen is not affected by additional coating of the plates with the recombinant silicatein and incubation with its enzymatic substrate, tetraethoxysilane (TEOS). However, the enzymatic modification of the plates by biosilica deposition on the protein-coated surface caused a marked increase in calcium phosphate formation of SaOS-2 cells as revealed by alizarin red-S staining to quantify calcium mineral content. The increased occurrence of calcium-phosphate nodules on the modified surface was also observed by scanning electron microscopy. These results suggest that by supporting calcium-phosphate deposition in vitro, biosilica (silicatein)-modified surfaces are potentially bioactive in vivo, by stimulating osteoblast mineralization function.

Human dental follicle precursor cells of wisdom teeth: isolation and differentiation towards osteoblasts for implants with and without scaffolds

“…It has been shown, that osteogenic cell types, like SaOS-2 need a phosphate source like ß-glycerolphosphate for mineralization [34], which has been used in this study.…”

Bioinspired Fabrication of Bio‐Silica‐Based Bone‐Substitution Materials

“…[24,25] Bio-silica is a product of the enzyme silicatein, [26][27][28] that uses its substrate, monomeric silica, to form polysilicate. Silicatein represents the first enzyme that is able to mediate the synthesis of an inorganic polymer, polysilicate/bio-silica.…”

“…Hence, a burst of silicon accumulation was seen around the osteoid and osteoid-bone interfaces, suggesting that this inorganic component is essential for bone formation. [32][33][34][35] Previous studies demonstrate that bio-silica combines two highly valued properties: it is osteoinductive [24,25] and it operates as a biologized, solid matrix for cells that control hydroxyapatite formation. [25] The present study aims to explore these properties in the context of a novel bonesubstitution material.…”

Inorganic Polymers: Morphogenic Inorganic Biopolymers for Rapid Prototyping Chain

“…Biosilica, produced by silicatein, turned out to be morphogenetically active: it induces hydroxyapatite (HA) formation in osteoblast-like SaOS-2 cells (Schröder et al 2005). In addition, it upregulates the expression of BMP-2 (Wiens et al 2010b), an inducer of bone formation and bone regeneration (see Nickel et al 2001).…”