Abstract
Magnetic stimulation has been applied to bone regeneration, however, the cellular and molecular mechanisms of repair still require a better understanding. A three-dimensional (3D) collagen model was developed using plastic compression, which produces dense, cellular, mechanically strong native collagen structures. Osteoblast cells (MG-63) and magnetic iron oxide nanoparticles (IONPs) were incorporated into collagen gels to produce a range of cell-laden models. A magnetic bio-reactor to support cell growth under static magnetic fields (SMFs) was designed and fabricated by 3D printing. The influences of SMFs on cell proliferation, differentiation, extracellular matrix production, mineralisation and gene expression were evaluated. Polymerase chain reaction (PCR) further determined the effects of SMFs on the expression of runt-related transcription factor 2 (Runx2), osteonectin (ON), and bone morphogenic proteins 2 and 4 (BMP-2 and BMP-4). Results demonstrate that SMFs, IONPs and the collagen matrix can stimulate the proliferation, alkaline phosphatase production and mineralisation of MG-63 cells, by influencing matrix/cell interactions and encouraging the expression of Runx2, ON, BMP-2 and BMP-4. Therefore, the collagen model developed here not only offers a novel 3D bone model to better understand the effect of magnetic stimulation on osteogenesis, but also paves the way for further applications in tissue engineering and regenerative medicine.
Highlights
For more than a century, investigators have been developing alternative treatments that have aimed to resolve the bone fracture healing process, by physical or biological methods
At day 14, significant differences between static magnetic fields (SMFs), iron oxide nanoparticles (IONPs) and the combined on cell proliferation were observed. This demonstrates that employing SMFs or IONPs alone can only stimulate cell proliferation up to 7 days, whereas by combining both factors, the effect can be extended until 14 days
By visualising the functional cells inside the collagen scaffolds, the effects of SMFs and IONPs on cell proliferation examined by the AB assay can be validated
Summary
For more than a century, investigators have been developing alternative treatments that have aimed to resolve the bone fracture healing process, by physical or biological methods. During tissue development and repair processes, collagen can interact directly with cells and influence several cellular activities, including adhesion, growth, differentiation, mineralisation of ECM, as well as the expression of growth factors and cytokines[15,18,19] Due to these advantages, a large number of applications based on collagen hydrogels can be found, such as nerve guide tubes for peripheral nerves[20], scaffolds for connective tissues21, 3D tumour models[11,22], hematopoietic niche models[23] to study the biological behaviours of various cells and genes[24,25,26,27,28,29,30]. Chitosan[35] and bioactive glass particles[36] have been incorporated into PC systems to enhance cell differentiation and mineralisation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
