3D Printed Graphene-PLA Scaffolds Promote Cell Alignment and Differentiation.

Traumas and chronic damages can hamper the regenerative power of nervous, muscle, and connective tissues. Tissue engineering approaches are promising therapeutic tools, aiming to develop reliable, reproducible, and economically affordable synthetic scaffolds which could provide sufficient biomimetic cues to promote the desired cell behaviour without triggering graft rejection and transplant failure. Here, we used 3D-printing to develop 3D-printed scaffolds based on either PLA or graphene@PLA with a defined pattern. Multiple regeneration strategies require a specific orientation of implanted and recruited cells to perform their function correctly. We tested our scaffolds with induced pluripotent stem cells (iPSC), neuronal-like cells, immortalised fibroblasts and myoblasts. Our results demonstrated that the specific "lines and ridges" 100 µm-scaffold topography is sufficient to promote myoblast and fibroblast cell alignment and orient neurites along with the scaffolds line pattern. Conversely, graphene is critical to promote cells differentiation, as seen by the iPSC commitment to neuroectoderm, and myoblast fusions into multinuclear myotubes achieved by the 100 µm scaffolds containing graphene. This work shows the development of a reliable and economical 3D-printed scaffold with the potential of being used in multiple tissue engineering applications and elucidates how scaffold micro-topography and graphene properties synergistically control cell differentiation.