Mechanically reinforced 3D-bioprinted hydrogels with reconstructed chondrogenic microenvironments for nasal cartilage regeneration

Cartilage grafts used in rhinoplasty and trauma repair face limitations in terms of long-term structural stability and regenerative capacity. Here, we developed a three-dimensional (3D)-bioprinted hydrogel system based on gelatin methacryloyl, hyaluronic acid methacrylate, and silk fibroin methacrylate, which incorporated rat chondrocytes, bone marrow mesenchymal stem cells, and transforming growth factor β1 to enable anatomically precise nasal cartilage reconstruction. This 3D-bioprinted hydrogel system exhibited controlled degradation kinetics and reinforced mechanical properties, providing a structural microenvironment that supported cellular condensation and cartilage-specific extracellular matrix deposition. Its optimized rheological and crosslinking characteristics ensured the fabrication of complex nasal architectures with high geometric accuracy. Subcutaneous implantation and culture results in nude mice indicated that the proposed 3D-bioprinted hydrogel system maintained structural stability and generated mature ectopic cartilage with sustained shape retention. Moreover, the compressive modulus of the regenerated tissue ((2.21±0.58) MPa) was significantly higher than that of the initial scaffold, and approached the reported range of native rat cartilage. Overall, this structurally stable and bioactive 3D-bioprinted hydrogel system is a promising strategy for anatomically precise nasal cartilage reconstruction.