Biodegradable and Biocompatible Graphene-based Scaffolds for Functional
Neural Tissue Engineering: A Strategy Approach Using Dental Pulp Stem
Cells and Biomaterials
Abstract
Neural tissue engineering aims to restore function of nervous system
tissues using biocompatible cell-seeded scaffolds. Graphene-based
scaffolds combined with stem cells deserve special attention to enhance
tissue regeneration in a controlled manner. However, it is believed that
minor changes in scaffold biomaterial composition, internal porous
structure, and physicochemical properties can impact cellular growth and
adhesion. The current work aims to investigate in vitro biological
effects of 3D graphene oxide (GO)/sodium alginate (GOSA) and reduced
GOSA (RGOSA) scaffolds on dental pulp stem cells (DPSCs) in terms of
cell viability and cytotoxicity. Herein, the effects of the 3D
scaffolds, coating conditions, and serum supplementation on DPSCs
functions are explored extensively. Biodegradation analysis revealed
that addition of GO enhanced the degradation rate of composite
scaffolds. Compared to the 2D surface, the cell viability of 3D
scaffolds was higher (p <0.0001), highlighting the optimal
initial cell adhesion to the scaffold surface and cell migration through
pores. Moreover, the cytotoxicity study indicated that the incorporation
of graphene supported higher DPSCs viability. It is also shown that when
the mean pore size of scaffold increases, DPSCs activity decreases. In
terms of coating conditions, poly-l-lysine (PLL) was the most robust
coating reagent that improved cell-scaffold adherence and DPSCs
metabolism activity. The cytotoxicity of GO-based scaffolds showed that
DPSCs can be seeded in serum-free media without cytotoxic effects. This
is critical for human translation as cellular transplants are typically
serum-free. These findings suggest that proposed 3D GO-based scaffolds
have favourable effects on the biological responses of DPSCs.