Endothelial cell colonization and angiogenic potential of combined nano- and micro-fibrous scaffolds for bone tissue engineering
Presently the majority of tissue engineering approaches aimed at regenerating bone relies only on postimplantation vascularization. Strategies that include seeding endothelial cells (ECs) on biomaterials and promoting their adhesion, migration and functionality might be a solution for the formation of vascularized bone. Nano/micro-fiber-combined scaffolds have an innovative structure, inspired by extracellular matrix (ECM) that combines a nano-network, aimed to promote cell adhesion, with a micro-fiber mesh that provides the mechanical support. In this work we addressed the influence of this nano-network on growth pattern, morphology, inflammatory expression profile, expression of structura…
Crosstalk between osteoblasts and endothelial cells co-cultured on a polycaprolactone-starch scaffold and the in vitro development of vascularization.
The reconstruction of bone defects based on cell-seeded constructs requires a functional microvasculature that meets the metabolic demands of the engineered tissue. Therefore, strategies that augment neovascularization need to be identified. We propose an in vitro strategy consisting of the simultaneous culture of osteoblasts and endothelial cells on a starch-based scaffold for the formation of pre-vascular structures, with the final aim of accelerating the establishment of a vascular bed in the implanted construct. Human dermal microvascular endothelial cells (HDMECs) were co-cultured with human osteoblasts (hOBs) on a 3D starch-based scaffold and after 21 days of culture HDMEC aligned and…
Rapid vascularization of starchâ poly(caprolactone) in vivo by outgrowth endothelial cells in co-culture with primary osteoblasts
The successful integration of in vitro-generated tissues is dependent on adequate vascularization in vivo. Human outgrowth endothelial cells (OECs) isolated from the mononuclear cell fraction of peripheral blood represent a potent population of circulating endothelial progenitors that could provide a cell source for rapid anastomosis and scaffold vascularization. Our previous work with these cells in co-culture with primary human osteoblasts has demonstrated their potential to form perfused vascular structures within a starch–poly(caprolactone) biomaterial in vivo. In the present study, we demonstrate the ability of OECs to form perfused vascular structures as early as 48 h following subcut…
Surface-modified 3D starch-based scaffold for improved endothelialization for bone tissue engineering
Providing adequate vascularization is one of the main hurdles to the widespread clinical application of bone tissue engineering approaches. Due to their unique role in blood vessel formation, endothelial cells (EC) play a key role in the establishment of successful vascularization strategies. However, currently available polymeric materials do not generally support EC growth without coating with adhesive proteins. In this work we present argon plasma treatment as a suitable method to render the surface of a 3D starch-based scaffold compatible for ECs, this way obviating the need for protein pre-coating. To this end we studied the effect of plasma modification on surface properties, protein …
Synthesis, mechanical and thermal rheological properties of new gellan gum derivatives
New derivatives of gellan gum (GG) were prepared by covalent attachment of octadecylamine (C18- NH2) to polysaccharide backbone via amide linkage by using bis(4-nitrophenyl) carbonate (4-NPBC) as a coupling agent. The effect of the alkyl chain grafted onto hydrophilic backbone of high molecular weight GG was investigated in terms of physicochemical properties and ability of new derivatives to form hydrogels. A series of hydrogels was obtained in solutions with different kind and concentration of ions and their stability and mechanical properties were evaluated. The obtained derivatives resulted soluble at temperature lower than starting GG and physicochemical properties of obtained hydrogel…
Microfluidic production of hyaluronic acid derivative microfibers to control drug release
"Available online 4 July 2016"
Biological performance of cell-encapsulated methacrylated gellan gum-based hydrogels for nucleus pulposus regeneration
Limitations of current treatments for intervertebral disc (IVD) degeneration have promoted interest in the development of tissue-engineering approaches. Injectable hydrogels loaded with cells can be used as a substitute material for the inner IVD part, the nucleus pulposus (NP), and provide an opportunity for minimally invasive treatment of IVD degeneration. The NP is populated by chondrocyte-like cells; therefore, chondrocytes and mesenchymal stem cells (MSCs), stimulated to differentiate along the chondrogenic lineage, could be used to promote NP regeneration. In this study, the in vitro and in vivo response of human bone marrow-derived MSCs and nasal chondrocytes (NCs) to modified gellan…
Contribution of outgrowth endothelial cells from human peripheral blood on in vivo vascularization of bone tissue engineered constructs based on starch polycaprolactone scaffolds
In the present study we assessed the potential of human outgrowth endothelial cells (OEC), a subpopulation within endothelial progenitor cell cultures, to support the vascularization of a complex tissue engineered construct for bone. OEC cultured on starch polycaprolactone fiber meshes (SPCL) in monoculture retained their endothelial functionality and responded to angiogenic stimulation by VEGF (vascular endothelial growth factor) in fibrin gel-assays in vitro. Co-culture of OEC with human primary osteoblasts (pOB) on SPCL, induced an angiogenic activation of OEC towards microvessel-like structures achieved without additional supplementation with angiogenic growth factors. Effects of co-cul…
Response of micro- and macrovascular endothelial cells to starch-based fiber meshes for bone tissue engineering.
The establishment of a functional vasculature is as yet an unrealized milestone in bone reconstruction therapy. For this study, fiber-mesh scaffolds obtained from a blend of starch and poly(caprolactone) (SPCL), that have previously been shown to be an excellent material for the proliferation and differentiation of bone marrow cells and thereby represent great potential as constructs for bone regeneration, were examined for endothelial cell (EC) compatibility. To be successfully applied in vivo, this tissue engineered construct should also be able to support the growth of ECs in order to facilitate vascularization and therefore assure the viability of the construct upon implantation. The ma…