Thickening tissue by thinning electrospun scaffolds for skeletal muscle tissue engineering

Abstract Electrospun scaffolds with aligned fiber orientation are widely used in tissue engineering, such as muscle, heart, nerve, tendon, and cartilage, due to their ability to guide cell morphology and induce cellular functions. However, the dense fibrous structure of the scaffolds poses a critical obstacle to engineering highly cellular and thick 3D tissues, as it prevents cell infiltration. While many techniques have been developed to increase the pore size of electrospun scaffolds and improve cell infiltration/migration, it often leads to a decrease in direct cell‐cell contact, compromising cell differentiation and tissue maturation. This study presents an alternative approach by reducing the thickness of scaffolds to the cellular scale and stacking or rolling the cell‐scaffold complex into 3D constructs. We devise a series of novel tools to fabricate, characterize, and manipulate ultra‐thin electrospun scaffolds, which demonstrate high reproducibility, resolution, and cellularity. Our study provides a solution to the cell infiltration issue in muscle tissue engineering and is highly versatile, and can be applied to various fields that require structures with high‐resolution gradients in a layered pattern or complex spatial distribution in a rolled pattern.