Smooth muscle matrix bioink promotes myogenic differentiation of encapsulated adipose-derived stem cells

Hydrogels derived from decellularized extracellular matrices (dECM) can mimic the biochemical composition of the native tissue. They can also act as a template to culture reseeded cells in vitro. However, detergent-based decellularization methods are known to alter the biochemical compositions, thereby compromising the bioactive potential of dECM. This study proposes a facile detergent-free method to achieve dECM from smooth muscle tissue. We have used the muscle layer of caprine esophageal tissue and decellularized using hypo and hyper-molar sodium chloride solutions alternatingly. Then, a hydrogel was prepared from this decellularized smooth muscle matrix (dSMM) and characterized thoroughly. A comparative analysis of the dSMM prepared with our protocol with the existing detergent-based protocol suggests successful and comparable decellularization with minimal residual DNA content. Interestingly, an 8.78-fold increase in sulfated glycosaminoglycans content and 1.62-fold increased collagen content indicated higher retention of ECM constituents with NaCl-based decellularization strategy. Moreover, the dSMM gel induces differentiation of the encapsulated adipose-derived mesenchymal stem cells toward smooth muscle cells (SMCs) as observed by their expression of alpha-smooth muscle actin and smooth muscle myosin heavy chain, the hallmarks of SMCs. Finally, we optimized the process parameter for productive bioprinting with this dSMM bioink and fabricated 3D muscle constructs. Our results suggest that dSMM has the potential to be used as a bioink to engineer personalized esophageal tissues.