Influence of mechanical properties of alginate-based substrates on the performance of Schwann cells in culture

Abstract

In tissue engineering, artificial tissue scaffolds containing living cells have been studied for tissue repair and regeneration. Notably, the performance of these encapsulated-in-scaffolds cells in terms of cell viability, proliferation, and expression of function during and after the scaffold fabrication process, has not been well documented because of the influence of mechanical, chemical, and physical properties of the scaffold substrate materials. This paper presents our study on the influence of mechanical properties of alginate-based substrates on the performance of Schwann cells, which are the major glial cells of peripheral nervous system. Given the fact that alginate polysaccharide hydrogel has poor cell adhesion properties, in this study, we examined several types of cell-adhesion supplements and found that alginate covalently modified with RGD peptide provided improved cell proliferation and adhesion. We prepared alginate-based substrates for cell culture using varying alginate concentrations for altering their mechanical properties, which were confirmed by compression testing. Then, we examined the viability, proliferation, morphology, and expression of the extracellular matrix protein laminin of Schwann cells that were seeded on the surface of alginate-based substrates (or 2D culture) or encapsulated within alginate-based substrates (3D cultures), and correlated the examined cell performance to the alginate concentration (or mechanical properties) of hydrogel substrates. Our findings suggest that covalent attachment of RGD peptide can improve the success of Schwann cell encapsulation within alginate-based scaffolds, and provide guidance for regulating the mechanical properties of alginate-based scaffolds containing Schwann cells for applications in peripheral nervous system regeneration and repair.

Applications of Alginate-Based Bioinks in 3D Bioprinting

“…With respect to basic research, in a work by Ning et al [56], the flow behavior of alginate solutions containing living cells was studied. Rheological properties of alginate–Schwann cell, alginate–fibroblast cell, and alginate–skeletal muscle cell suspensions during shearing in the printing process were analyzed, confirming that the flow behavior effects on cells are critical for their viability and proliferation: in addition to temperature and the concentration of the biomaterial, the cell density affects the flow behavior of cell suspensions too.…”

Influence of crosslinking on the mechanical behavior of 3D printed alginate scaffolds: Experimental and numerical approaches

“…In some tissue engineering applications, such as peripheral nerve (Ning et al, 2016), bone (Naghieh et al, 2016b), and articular cartilage (You et al, 2016b) regeneration, scaffolds undergo compressive force exerted by over-and underlying tissues in one direction. In such cases, the compressive elastic modulus is important in one direction while the scaffold mechanical behavior in other directions might be different; indeed, bioprinted scaffolds are not isotropic (Olubamiji et al, 2016).…”

Engineering a Cell Home for Stem Cell Homing and Accommodation

“…Analogously, using an advanced bioreactor system, the impact of tensile forces on cell differentiation within a 3D collagen construct was demonstrated when uniaxial static or dynamic stretch was utilized on mouse ESC‐embedded matrices . When Schwann cells were encapsulated within alginate‐based hydrogels using varying alginate concentrations, the mechanical properties of the materials exerted an important effect on the performance of these cells . Interestingly, recent evidence demonstrated that 3D mechanical stimulation could replace chemical pre‐stimulation ( e.g ., TGF‐β1) to yield smooth muscle cells from adipose tissue‐derived stromal cells, offering a novel approach to engineering bioartificial arteries in vascular tissue engineering .…”