Decellularization of skeletal muscle for tissue engineering

Skeletal muscle has an inherent regenerative capacity due to the presence of a population of dedicated stem cells, called satellite cells. However, traumatic injuries, congenital or acquired diseases still result in an irrecoverable loss of muscle function. Current management of volumetric muscle loss injuries is limited to scar tissue debridement and placement of muscle flaps around the site of tissue defects. However, these clinical options are inefficient and the outcomes remain aesthetically and functionally deficient. Therefore, there is a great demand for developing new therapeutic strategies for volumetric muscle loss such as skeletal muscle tissue engineering. This approach combines supportive structures (scaffolds) with stem cells and growth factors to grow skeletal muscle in vitro. Ideally, a biomaterial scaffold mimics the natural skeletal muscle extracellular matrix because it plays a key role in the proliferation and differentiation of muscle progenitor cells and has suitable mechanical characteristics. Despite the advances in biomaterials fabrication, none of the current scaffolds materials meet all these criteria. Therefore, interest has shifted towards the use of decellularized matrices as scaffolds for regeneration. At the moment -although these decellularized scaffolds are referred to as 3D- they are still very thin (submillimeter). With our work, we are comparing the efficiency of decellularization protocols on larger pieces of skeletal muscle tissue. Results show qualitative differences in DNA removal, glycosaminoglycan content, collagen content and overall tissue structure preservation. In conclusion, this comparison paves the way towards decellularization of skeletal muscle tissue in clinically relevant sizes, which offers a promising approach towards regenerative medicine.