Bio-printing of aligned GelMa-based cell-laden structure for muscle tissue regeneration

Volumetric muscle loss (VML) is associated with a severe loss of muscle tissue that overwhelms the regenerative potential of skeletal muscles. Tissue engineering has shown promise for the treatment of VML injuries, as evidenced by various preclinical trials. The present study describes the fabrication of a cell-laden GelMa muscle construct using an in situ crosslinking (ISC) strategy to improve muscle functionality. To obtain optimal biophysical properties of the muscle construct, two UV exposure sources, UV exposure dose, and wall shear stress were evaluated using C2C12 myoblasts. Additionally, the ISC system showed a significantly higher degree of uniaxial alignment and myogenesis compared to the conventional crosslinking strategy (post-crosslinking). To evaluate the in vivo regenerative potential, muscle constructs laden with human adipose stem cells were used. The VML defect group implanted with the bio-printed muscle construct showed significant restoration of functionality and muscular volume. The data presented in this study suggest that stem cell-based therapies combined with the modified bioprinting process could potentially be effective against VML injuries. [Display omitted] •A new bioprinting system using myoblasts and stem cells was investigated for muscle regeneration.•Efficient myogenesis was achieved on the new bioprinted structure compared to the conventional bioprinted structure.•The bioprinted structure significantly accelerated tibialis anterior muscle recovery on mouse model.