Electrospun Collagen: A Tissue Engineering Scaffold with Unique Functional Properties in a Wide Variety of Applications

Figure 6

Muscle Fabrication: 8 Weeks. (a) Low magnification survey image depicting the terminal portions of muscle tissue engineered in situ. Images depicted in panels (b) and (c) were taken from the cross-sectional area denoted as “B” and “C”, respectively in panel (a). The tissue distal to the attachment sites exhibited stacked arrays of myotubes ((b), asterisks). Tissue alignment is disrupted to some degree at the distal attachment sites as a consequence of the sutures used to place the tissue ((c), arrows indicate functional blood vessels). Myofibril density is observed to vary within cells that are in close proximity to one another ((d), arrowheads and asterisk; also the myofibrillar density in (d) and (e) to (g) and (h)) and some subdomains of the tissue stain differentially at both the light (g) and EM levels (h) with stains designed to enhanced contrast. The tissue is highly biosynthetic as evidence by the accumulation of proteins in the vicinity of the nuclei and golgi (g, asterisk). A subset of engineered tissue exhibits sarcomeres (f) with unusual cytoarchitectural patterns at the Z bands (arrows) and H zones (arrowheads) characterized by accessory electron dense structures. At the ultrastructural level, the implants are surrounded by collagen fibrils ((i) asterisks).