Like the morphology of native tissue fiber arrangement (such as skeletal muscle), unidirectional anisotropic scaffolds are highly desired as a means to guide cell behavior in anisotropic tissue engineering. In contrast, contour-like staircases exhibit directional topographical cues and are judged as an inevitable defect of fused deposition modeling (FDM). In this study, we will translate this staircase defect into an effective bioengineering strategy by integrating FDM with surface coating technique (FCT) to investigate the effect of topographical cues on regulating behaviors of human mesenchymal stem cells (hMSCs) toward skeletal muscle tissues. This integrated approach serves to fabricate shape-specific, multiple dimensional, anisotropic scaffolds using different biomaterials. 2D anisotropic scaffolds, first demonstrated with different polycaprolactone concentrations herein, efficiently direct hMSC alignment, especially when the scaffold is immobilized on a support ring. By surface coating the polymer solution inside FDM-printed sacrificial structures, 3D anisotropic scaffolds with thin wall features are developed and used to regulate seeded hMSCs through a self-established rotating bioreactor. Using layer-by-layer coating, along with a shape memory polymer, smart constructs exhibiting shape fix and recovery processes are prepared, bringing this study into the realm of 4D printing. Immunofluorescence staining and real-time quantitative polymerase chain reaction analysis confirm that the topographical cues created via FCT significantly enhance the expression of myogenic genes, including myoblast differentiation protein-1, desmin, and myosin heavy chain-2. We conclude that there are broad application potentials for this FCT strategy in tissue engineering as many tissues and organs, including skeletal muscle, possess highly organized and anisotropic extracellular matrix components.
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Etching anisotropic surface topography onto fibrin microthread scaffolds for guiding myoblast alignment
To regenerate functional muscle tissue, engineered scaffolds should impart topographical features to induce myoblast alignment by a phenomenon known as contact guidance. Myoblast alignment is an essential step towards myotube formation, which is guided
- NSF-PAR ID:
- 10406196
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Biomedical Materials Research Part B: Applied Biomaterials
- Volume:
- 108
- Issue:
- 5
- ISSN:
- 1552-4973
- Page Range / eLocation ID:
- p. 2308-2319
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Advancements in tissue engineering and biomaterial development have the potential to provide a scalable solution to the problem of large‐volume skeletal muscle defects. Previous research on the development of scaffolds for skeletal muscle regeneration has focused on strategies for increasing conductivity, which has improved satellite cell attachment and differentiation. However, these strategies usually increase scaffold stiffness, which some studies suggest may be detrimental to myoblast development. In this study, the polymers polypyrrole (PPy) and polycaprolactone (PCL) were synthesized together into a copolymer (PPy–PCL) designed to increase scaffold conductivity without significantly influencing stiffness. Different scaffold groups were fabricated via electrospinning, characterized, and assessed for their suitability for myoblast proliferation and differentiation. The groups included an aligned and random iteration of pure PCL, 10% PPy–PCL, 20% PPy–PCL, and 40% PPy–PCL. Only the 40% PPy–PCL group had a measureable conductivity, and the addition of PPy–PCL had no significant effect on the stiffness of the scaffolds. The PPy–PCL copolymer significantly increased the attachment of C2C12 myoblasts as compared to pure PCL scaffolds, but the concentration of PPy–PCL did not significantly alter cell attachment. In addition, scaffolds with PPy–PCL promoted myoblast differentiation to a greater extent than scaffolds made of PCL as measured by fusion index and number of nuclei per myotube. Aligned scaffolds were superior to random scaffolds in almost all measures. These results suggest that conductivity may not be the key factor in improving skeletal muscle scaffolds. Instead, cell attachment and aligned guidance cues may have a greater impact on myoblast differentiation. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 220–231, 2019.
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Abstract Graphene, owing to its inherent chemical inertness, biocompatibility, and mechanical flexibility, has great potential in guiding cell behaviors such as adhesion and differentiation. However, due to the two-dimensional (2D) nature of graphene, the microfabrication of graphene into micro/nanoscale patterns has been widely adopted for guiding cellular assembly. In this study, we report crumpled graphene, i.e., monolithically defined graphene with a nanoscale wavy surface texture, as a tissue engineering platform that can efficiently promote aligned C2C12 mouse myoblast cell differentiation. We imparted out-of-plane, nanoscale crumpled morphologies to flat graphene via compressive strain-induced deformation. When C2C12 mouse myoblast cells were seeded on the uniaxially crumpled graphene, not only were the alignment and elongation promoted at a single-cell level but also the differentiation and maturation of myotubes were enhanced compared to that on flat graphene. These results demonstrate the utility of the crumpled graphene platform for tissue engineering and regenerative medicine for skeletal muscle tissues.
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