Building better scaffolding materials for tissue regrowth is one important line of work in the regenerative medicine. The idea is to better mimic necessary characteristics of the natural extracellular matrix, to make the cells inhabiting the scaffold material behave in ways that are conducive to regrowth and regeneration. The open access paper noted here is an example of this sort of ongoing research and development, tackling one small aspect of scaffold materials for one tissue type.
To achieve rapid skeletal muscle function restoration, many attempts have been made to bioengineer functional muscle constructs by employing physical, biochemical, or biological cues. Here, we develop a self-aligned skeletal muscle construct by printing a photo-crosslinkable skeletal muscle extracellular matrix-derived bioink together with poly(vinyl alcohol) that contains human muscle progenitor cells.
To induce the self-alignment of human muscle progenitor cells, in situ uniaxially aligned micro-topographical structure in the printed constructs is created by a fibrillation/leaching of poly(vinyl alcohol) after the printing process. The in vitro results demonstrate that the synergistic effect of tissue-specific biochemical signals, obtained from the skeletal muscle extracellular matrix-derived bioink, and topographical cues, obtained from the poly(vinyl alcohol) fibrillation, improves the myogenic differentiation of the printed human muscle progenitor cells with cellular alignment. Moreover, this self-aligned muscle construct shows the accelerated integration with neural networks and vascular ingrowth in vivo, resulting in rapid restoration of muscle function.
Thus we demonstrate that combined biochemical and topographic cues on the 3D bioprinted skeletal muscle constructs can effectively reconstruct the extensive muscle defect injuries.