Saos‐2 cell‐mediated mineralization on collagen gels: Effect of densification and bioglass incorporation

Abstract

Plastic compression is a collagen densification process that has been widely used for the development of mechanically robust collagen-based materials. Incorporation of bioglass within plastically compressed collagen gels has been shown to mimic the microstructural properties of native bone and enhance in vitro cell-mediated mineralization. The current study seeks to decouple the effects of collagen densification and bioglass incorporation to understand the interplay between collagen packing density and presence of bioglass on cell-mediated mineralization. Saos-2 cell-mediated mineralization was assessed as a measure of the osteoconductivity of four different collagen gels: (1) uncompressed collagen gel (UC), (2) bioglass incorporated uncompressed collagen gel (UC + BG), (3) plastically compressed collagen gel (PC), and (4) bioglass incorporated plastically compressed collagen gel (PC + BG). The results indicated that collagen densification enhanced mineralization as shown by SEM, increased alkaline phosphatase activity and produced significantly higher amounts of mineralized nodules on PC gels compared to UC gels. Further, the amount of nodule formation on PC gels was significantly higher compared to UC + BG gels indicating that increase in matrix stiffness due to collagen densification had a greater effect on cell-mediated mineralization compared to bioglass incorporation into loosely packed UC gels. Incorporation of bioglass into PC gels further enhanced mineralization as evidenced by significantly larger nodule size and higher amount of mineralization on PC + BG gels compared to PC gels. In conclusion, collagen densification via plastic compression improves the osteoconductivity of collagen gels. Further, incorporation of bioglass within PC gels has an additive effect and further enhances the osteoconductivity of collagen gels.

Photochemically crosslinked cell‐laden methacrylated collagen hydrogels with high cell viability and functionality

“…However, cell viability, metabolic activity, and functionality were better preserved in CMA hydrogels photochemically crosslinked with VA086 compared to I2959. Although short‐term culture (i.e., 7 days) using Saos‐2 cells is a good model to assess the biocompatibility of collagen‐based hydrogels, future studies will build upon this work and assess tissue‐specific cellular differentiation of human mesenchymal stem cells using longer term cultures (i.e., up to 4 weeks). CMA hydrogel in combination with I2959 has been used as bio‐ink for 3D bioprinting applications .…”

“…Saos‐2 cells can serve as a model osteoblast cell line due to their ability to deposit a calcified matrix in vitro . The effect of different photochemical crosslinking conditions on Saos‐2 cell‐mediated mineralization was assessed as a measure of in vitro cell functionality.…”

“…Effect of photochemical crosslinking conditions on Saos-2 cell-mediated mineralization Saos-2 cells can serve as a model osteoblast cell line due to their ability to deposit a calcified matrix in vitro. 32,33 The effect of different photochemical crosslinking conditions on Saos-2 cellmediated mineralization was assessed as a measure of in vitro cell functionality. After 7 days of culture, 10 −7 M dexamethasone (Sigma-Aldrich) was added into the culture medium.…”

Hydrogels: soft matters in photomedicine

“…173 Furthermore, small deformation rheology experiments, such as small amplitude oscillatory shear (SAOS), are used to determine critical hydrogel properties. 174 The applied shear stress (s*) is measured via the stress transducer, whereas g*, the stress induced in the sample, is measured via a strain transducer. 175 Furthermore, the complex modulus of the material is calculated using Equation 1.…”

Magnesium Modifies the Structural Features of Enzymatically Mineralized Collagen Gels Affecting the Retraction Capabilities of Human Dermal Fibroblasts Embedded within This 3D System

“…Nevertheless, an appropriate collagen structure is necessary to guide crystal growth and organization [5], allowing proper collagen-mineral interactions, infiltration of calcium and phosphate within collagen fibrils, as well as hydroxyapatite nucleation [8,9,10]. Collagen gel mineralization has been either obtained by incorporating hydroxyapatite [11,12], by seeding cells cultured for several days in the presence of pro-osteogenic supplements as β-glycerophosphate and ascorbic acid [13,14,15], or by preparing collagen/calcium phosphate multilayers, where mineralization is the result of enzymatic reactions [16] and cells are only spread on the matrix surface. Interestingly, stem cells ( i.e.…”