Recent progress on 3D-printed gelatin methacrylate-based biomaterials for articular cartilage repair

The structure and composition of articular cartilage is complex, and its self-healing ability is limited, and thus, it is difficult to achieve ideal healing once the articular cartilage is damaged. Recently, three-dimensional (3D) printing technology has provided a new possibility for the repair of articular cartilage. Engineered cartilage tissues can be fabricated by superimposing customized inks, considering different geometric structures and components of tissues. 3D printing can be effectively used to manufacture high-precision structures with complex geometry, solving the shortcomings of traditional scaffold fabrication techniques. Gelatin methacrylate (GelMA) is modified gelatin and is currently a widely used 3D printing ink due to its photocrosslinking properties. With good biocompatibility and tunable physical properties, it can provide a good scaffold platform for cell proliferation and growth factor release. Given that the role of 3D printing technology in cartilage repair has been widely reported, this article reviews the research progress of 3D-printed GelMA-based biomaterials in articular cartilage tissue engineering. We focus primarily on how 3D printing technology addresses the existing challenges inherent to the field of articular cartilage tissue engineering. We accentuate the modifications implemented in GelMA-based 3D printing scaffolds to optimize articular cartilage regeneration. Additionally, we provide a comprehensive summary of the utilization of GelMA-based biomaterials incorporating various cells, growth factors, or other tissue components and highlight how these adaptations, in conjunction with the benefits of 3D printing technology, facilitate improvements the articular cartilage repair.