The role of endothelial cells in myofiber differentiation and the vascularization and innervation of bioengineered muscle tissue in vivo

Abstract

Musculoskeletal disorders are a major cause of disability and effective treatments are currently lacking. Tissue engineering affords the possibility of new therapies utilizing cells and biomaterials for the recovery of muscle volume and function. A major consideration in skeletal muscle engineering is the integration of a functional vasculature within the regenerating tissue. In this study we employed fluorescent cell labels to track the location and differentiation of co-cultured cells in vivo and in vitro. We first utilized a co-culture of fluorescently labeled endothelial cells (ECs) and muscle progenitor cells (MPCs) to investigate the ability of ECs to enhance muscle tissue formation and vascularization in an in vivo model of bioengineered muscle. Scaffolds that had been seeded with both MPCs and ECs showed significantly greater vascularization, tissue formation and enhanced innervation as compared to scaffolds seeded with MPCs alone. Subsequently, we performed in vitro experiments using a 3-cell type system (ECs, MPCs, and pericytes (PCs)) to demonstrate the utility of fluorescent cell labeling for monitoring cell growth and differentiation. The growth and differentiation of individual cell types was determined using live cell fluorescent microscopy demonstrating the utility of fluorescent labels to monitor tissue organization in real time.

Design, evaluation, and application of engineered skeletal muscle

“…These studies revealed the importance of endothelial cells to pre-vascularize the construct and fibroblasts to promote vasculogenesis and stabilize the formed vessels [65]. Similarly, another study has identified the benefit of co-culturing endothelial cells and myoblasts on a urinary bladder matrix prior to subcutaneous implantation for tissue formation and vascular ingrowth in vivo [93]. …”

Endothelial Network Formation Within Human Tissue-Engineered Skeletal Muscle

“…Other tissue engineering approaches such as the use of soft hydrogels, the combination of endothelial cell sheets with myoblast cell sheets, and microfabrication techniques such as 3D printing may be more suitable to obtain aligned myofibers. 7,[9][10][11][12][13] Engineering muscle precursor cells in a soft hydrogel such as fibrin allows the myofibers to align in one direction while fibrin behaves as a proangiogenic, making it a good scaffold for both the formation of myofibers and endothelial networks.…”

“…44 Therefore, a direct comparison of these results with previous results in literature is difficult since different research groups not only use different types of fibrin but also different cell types, cell numbers, and volumes of ECM in tissue engineering of BAMs. 5,7,9,12,[18][19][20] To create muscle tissue similar to that in the adult body, still other hurdles need to be overcome. A major one is the formation of neuromuscular synapses.…”

Histological Evaluation of Decellularized Skeletal Muscle Tissue Using Two Different Decellularization Agents

“…Effective treatment of such defects can be prepared by tissue transplantation. Tissue engineering and regenerative medicine undergo significant development in the area of biomaterials and combination with stem cells offers accessible source for tissue reconstruction and transplantation (1)(2)(3)(4). Biological cell-free material can serve as an optimal scaffold for wide applications as it does not evoke an immune response.…”