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.

容积性肌肉损失 (VML) 与肌肉组织的严重损失有关，这种损失压倒了骨骼肌的再生潜力。各种临床前试验证明，组织工程已显示出治疗 VML 损伤的前景。本研究描述了使用原位交联 (ISC) 策略来改善肌肉功能的载有细胞的 GelMa 肌肉构造的制造。为了获得肌肉构造的最佳生物物理特性，使用 C2C12 成肌细胞评估了两个紫外线照射源、紫外线照射剂量和壁剪切应力。此外，与传统的交联策略（后交联）相比，ISC 系统显示出更高程度的单轴排列和肌生成。评估体内为了获得再生潜力，使用了载有人类脂肪干细胞的肌肉结构。植入生物打印肌肉结构的 VML 缺陷组显示出功能和肌肉体积的显着恢复。本研究中提供的数据表明，基于干细胞的疗法与改良的生物打印过程相结合，可能对 VML 损伤有效。