A tissue engineering approach for repairing craniofacial volumetric muscle loss in a sheep following a 2, 4, and 6-month recovery
Fig 2
Characterization of In vitro SMUs.
(A) The final modular assembly of n = 2 SMUs was 7cm long. (B) SMU monolayers prior to delamination showed abundant, networking myotubes. (C) Tetanic forces produced by sentinel SMUs were 72.0 ± 42.1μN on average. Red data points indicate the SMUs whose force peaked below the maximum current and/or frequency allowed by our force testing system. Masson’s trichrome staining of a single SMU cross-section (D) and modularly fused SMU cross-section (G) revealed an extracellular matrix composed of collagen. Immunohistochemical staining of a single SMU cross-section (E) and a modularly fused SMU (F) revealed the presence of muscle fibers (MF20, green) and laminin (red), as well as the presence of DAPI-stained nuclei (blue) throughout the thickness of the construct. (H) Immunostaining of a longitudinal section of a single SMU for desmin (red), α-smooth muscle actin (green), and DAPI (blue) revealed a parallel, linear arrangement of these proteins. (I, J) DAPI-stained nuclei (white) of the area denoted by the (I) dotted line box and the (J) hash line box in image (F). Scale bars on B, D-H = 500μm. Scale bars on I, J = 200μm.