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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Skeletal Muscle Constructs Engineered from Human Embryonic Stem Cell Derived Myogenic Progenitors Exhibit Enhanced Contractile Forces When Differentiated in a Medium Containing EGM‐2 Supplements
Three‐dimensional (3D) skeletal muscle constructs engineered from myogenic progenitors derived from human pluripotent stem cells (hPSCs) have a wide range of applications, but to date, such constructs generate lower specific tetanic force than adult human muscles. Methods enhancing functional muscle differentiation and force generation of these constructs are highly desirable. The finding of this study is that addition of the supplements in the endothelial cell growth medium‐2 (EGM‐2) to the myogenic differentiation medium can substantially enhance contractile force generation. For constructs differentiated for 4 weeks, addition of the EGM‐2 supplements in the first 2 weeks leads to tenfold and sevenfold increases in twitch and tetanic forces, respectively. The specific tetanic force generated by these constructs is 33 mN mm−2, which is significantly higher than previously reported. These constructs show wider myotubes and higher gene expression levels for all skeletal muscle‐specific myosin heavy chain isoforms, suggesting that a more mature differentiation stage of the cells underlies the greater contractile force generation. The constructs exposed to these supplements for 4 weeks do not generate as high contractile forces, suggesting that prolonged treatment is not beneficial. These results suggest that temporal conditioning with the EGM‐2 supplements assists functional development of hPSC‐derived skeletal muscle constructs.
more » « less- NSF-PAR ID:
- 10460040
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Biosystems
- Volume:
- 3
- Issue:
- 12
- ISSN:
- 2366-7478
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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