Pre-priming cell sheet therapy enabled by dynamic wrinkled electroactive substrate for muscle reconstruction.

Abstract

Current therapeutic approaches for muscle reconstruction face considerable challenges, particularly in generating sufficiently dense cell aggregates and in establishing effective methods for reactivating the function of exogenous cells. Herein, we developed a pre-priming cell sheet therapy for volumetric muscle loss (VML) that leverages highly dense, electro-mechanically bioactive constructs. To achieve this goal, we fabricated a multifunctional cell culture platform based on a near-infrared (NIR)-responsive, wrinkle-patterned, conductive substrate. This system enables scalable preparation (>6 mm in diameter), non-invasive harvesting, and bioactive pre-priming of cell sheets for transplantation. Non-invasive harvesting of the sheets is achieved via a NIR-triggered release mechanism, in which dynamic changes in wrinkle morphology induce a sufficient shift in mechanical stress at the cell-substrate interface, thereby disrupting focal adhesions. Compared with conventional cell-suspension therapy, the microstructured electroactive surface demonstrated superior efficacy for VML repair, as evidenced by integrated in vitro electrophysiology, RNA sequencing, and <i>in vivo</i> analysis. This enhancement is attributed to the substrate's provision of combined electrical and mechanical priming cues, which collectively promote myogenic differentiation, growth, and pro-regenerative calcium signaling in C2C12 myoblasts. In conclusion, this work establishes that engineering interfacial dynamics-rather than relying solely on static material properties-is pivotal for the development of advanced cell therapies. The dynamic electroactive substrate offers a versatile strategy for fabricating pre-functionalized tissue constructs, with immediate promise for regenerating electroexcitable tissues and broad application prospects in regenerative medicine.