Tissue Engineering of Skeletal Muscle

Abstract

Loss of skeletal muscle profoundly affects the health and well-being of patients, and there currently is no way to replace lost muscle. We believe that a key step in the development of a prosthesis for reconstruction of dysfunctional muscular tissue is the ability to reconstitute the in vivo-like 3-dimensional (3D) organization of skeletal muscle in vitro with isolated satellite cells. In our present proof of principle studies, we have successfully constructed a multilayered culture of skeletal muscle cells, derived from neonatal satellite cells, that are distributed in a 3D pattern of organization that mimics many of the features of intact tissue. These multilayered cultures are composed of elongated multinucleated myotubes that are MyoD positive. Histological studies indicate that the multiple layers of myotubes can be distinguished. Expression of muscle-specific markers such as myosin heavy chain, dystrophin, integrin alpha-7, alpha-enolase, and beta-enolase was detected using real-time reverse transcriptase polymerase chain reaction at levels near adult values. Physiological measurements of the engineered skeletal muscle showed that they tetanize and display physiologic force length behavior, although developed force per cross-sectional area was below that of native rat skeletal muscle.

In vivo tissue engineering of functional skeletal muscle by freshly isolated satellite cells embedded in a photopolymerizable hydrogel

“…This has represented a major limitation in previous studies (2,23), and growth factors have been suggested to improve nerve regeneration (24) and new capillary formation (25,26). In our experimental model, treated muscles showed the presence of neuromuscular junctions on both GFP ϩ and GFP Ϫ myofibers, as demonstrated through labeling with fluorescent ␣-bungarotoxin (Fig.…”

“…In vitro approaches based on fabrication of functional muscle before in vivo transplantation showed several limitations (2), due to the intrinsic complexity of large-organ reconstruction. Besides, it is well established that in mammals, skeletal muscle can repair its damaged areas only in the presence of a supporting scaffold (3).…”

The stimulation of myoblast differentiation by electrically conductive sub-micron fibers

“…We envisioned a composite fiber that could be utilized as a temporary substrate to stimulate tissue formation controlled by electrochemical signals as well as continuous mechanical stimulation under normal regeneration processes, i.e. muscular or neural tissue [24,25].…”

Hydrogel biomaterials and their therapeutic potential for muscle injuries and muscular dystrophies

“…Along with the structural maturation, these constructs were able to generate contractile force after two to four weeks in culture. Remarkably, these biomimetic muscles elicited contractile-force amplitudes of about 10-100 fold higher than previously described in vitro engineered muscles [43,162,164,165]. The in vivo behaviour of the engineered muscles was monitored using a mouse dorsal window implantation model.…”