3D Printing of Maturable Tissue Constructs Using a Cell‐Adaptable Nanocolloidal Hydrogel

Abstract 3D‐printed cell‐laden hydrogels as tissue constructs show great promise in generating living tissues for medicine. Currently, the maturation of 3D‐printed constructs into living tissues remains challenge, since commonly used hydrogels struggle to provide an ideal microenvironment for the seeded cells. In this study, a cell‐adaptable nanocolloidal hydrogel is created for 3D printing of maturable tissue constructs. The nanocolloidal hydrogel is composed of interconnected nanoparticles, which is prepared by the self‐assembly and subsequent photocrosslinking of the gelatin methacryloyl solutions. Cells can get enough space to grow and migrate within the hydrogel through squeezing the flexible nanocolloidal networks. Meanwhile, the nanostructure can promote the seeded cells to proliferate and produce matrix proteins through mechanotransduction. Using digital light process‐based 3D printing technology, it can rapidly customize cartilage tissue constructs. After implantation, these tissue constructs efficiently matured into cartilage tissues for the articular cartilage defect repair and ear cartilage reconstruction in vivo. The 3D printing of maturable tissue constructs using the nanocolloidal hydrogel shows potential for future clinical applications.