Collagen-Hydroxyapatite Scaffolds Induce Human Adipose Derived Stem Cells Osteogenic Differentiation In Vitro

Abstract

Mesenchymal stem cells (MSCs) play a crucial role in regulating normal skeletal homeostasis and, in case of injury, in bone healing and reestablishment of skeletal integrity. Recent scientific literature is focused on the development of bone regeneration models where MSCs are combined with biomimetic three-dimensional scaffolds able to direct MSC osteogenesis. In this work the osteogenic potential of human MSCs isolated from adipose tissue (hADSCs) has been evaluated in vitro in combination with collagen/Mg doped hydroxyapatite scaffolds. Results demonstrate the high osteogenic potential of hADSCs when cultured in specific differentiation induction medium, as revealed by the Alizarin Red S staining and gene expression profile analysis. In combination with collagen/hydroxyapatite scaffold, hADSCs differentiate into mature osteoblasts even in the absence of specific inducing factors; nevertheless, the supplement of the factors markedly accelerates the osteogenic process, as confirmed by the expression of specific markers of pre-osteoblast and mature osteoblast stages, such as osterix, osteopontin (also known as bone sialoprotein I), osteocalcin and specific markers of extracellular matrix maturation and mineralization stages, such as ALPL and osteonectin. Hence, the present work demonstrates that the scaffold per se is able to induce hADSCs differentiation, while the addition of osteo-inductive factors produces a significant acceleration of the osteogenic process. This observation makes the use of our model potentially interesting in the field of regenerative medicine for the treatment of bone defects.

Rapid Induction of Osteogenic Markers in Mesenchymal Stem Cells by Adipose-Derived Stromal Vascular Fraction Cells

“…2 and 3). Because this period is very short compared with the typical time required for the in vitro osteogenic differentiation of MSCs [33-35], we could not identify a proper positive osteogenic control and used only negative controls such as mono-cultured MSCs or SVF cells in all experiments.…”

Bone augmentation after ectopic implantation of a cell-free collagen-hydroxyapatite scaffold in the mouse

“…The development of new biomaterials able to restore the bone structure and functional properties represents a promising approach. The potential of novel collagen/hydroxyapatite biomimetic scaffolds has been previously analyzed to evaluate the physicochemical properties1214, as well as the capability of inducing bone formation in combination with human MSCs in vitro and in vivo 121422. In the present study, we have investigated the ability of this biomaterial of inducing ectopic bone formation in vivo , after transplantation in the mouse as a cell-free scaffold.…”

“…In order to improve the capacity of the bone substitute to recapitulate the chemical, physical and structural properties of the native young human bone and provide cells with the right osteogenic niche, the collagen I matrix has been combined with Magnesium-enriched hydroxyapatite (MHA)101214. The osteogenic capability of this material has already been analysed in vitro 2122 and its ability to produce bone augmentation after ectopic implantation in the animal has been observed21, but a comprehensive in vivo , histological and molecular characterization of the bone augmentation into the implanted biomaterial, without the use of growth factors or exogenous cells, requires further investigation.…”

Growth plate extracellular matrix-derived scaffolds for large bone defect healing

“…Long bones form by the coordinated process of endochondral ossification, with the postnatal growth and development of our limbs driven by the growth plates (also called the epiphyseal plates). The growth plate (GP) is known to contain members of the transforming growth factor (TGF)-β family, including bone morphogenetic protein (BMP), as well as vascular endothelial growth factor (VEGF) and Indian hedgehog (Ihh), which are known to be strongly osteoinductive (Alini et al, 1992;Anderson et al, 2000;Carlevaro et al, 2000;Gerber et al, 1999;Kronenberg, 2003;Nilsson et al, 2007;Qiu et al, 2015;Wang et al, 2004). Indeed, powdered demineralised GP has been shown to be osteoinductive in vivo, supporting the development of a bone ossicle following ectopic implantation into rats (Bigham et al, 2011).…”

“…Porous scaffolds produced using collagen and hydroxyapatite, the two main constituents of bone, have been shown to encourage osteogenesis of MSCs in vitro and can support bone regeneration in vivo (Calabrese et al, 2016;Chen et al, 2015;Cunniffe et al, 2010;Cunniffe and O'Brien, 2011;David et al, 2015;Gleeson et al, GM Cunniffe et al Growth plate ECM scaffold for bone repair 2010; Prosecka et al, 2015;Villa et al, 2015). Ideally scaffolds have an open interconnected pore structure, with pore sizes in the range of 85-325 µm best supporting osteogenesis (Karageorgiou and Kaplan, 2005;Murphy et al, 2010;O'Brien et al, 2007).…”