Bionic scaffolds with integrated structural components based on low-temperature deposition manufacturing 3D printing technology for the treatment of meniscus defects.

Tissue engineering provides a promising avenue for treating meniscus defects. In this study, a novel polycaprolactone (PCL)/collagen type I (COL I) meniscus scaffold was fabricated using low temperature deposition manufacturing (LDM) 3D printing technology. The scaffold had a ring and radial fiber structure, and its composition and structure were double bionic of the natural meniscus. In vitro experiments showed that the scaffold had good biological properties, which could promote the proliferation of meniscus fibrochondrocytes (MFCs) and increase the secretion of collagen and glycosaminoglycan. Moreover, the scaffold had excellent mechanical properties and could withstand various stress loads from the femur and tibia. The integrity of the scaffold structure was maintained to provide sufficient time and space for tissue regeneration. The PCL/ COL I scaffold has shown good therapeutic effect in a rabbit meniscus defect model and promotes meniscus regeneration. The results of experiments in rabbits suggest that the scaffold may recruit stem cells and differentiate into fibrochondrocytes in the knee joint, which needs to be verified by further experiments. This study introduces a method of fabricating a new structural composition double bionic meniscus scaffold by LDM technology and verifies its ability to promote cell proliferation, increase the secretion of the extracellular matrix of fibrocartilage, and regulate the microenvironment of cell growth. In addition, this scaffold has achieved good results in repairing meniscus defects in small animal models. Our findings strongly indicate that the PCL/COL I biomimetic meniscus scaffold prepared using 3D-LDM technology holds great promise for repairing and regenerating damaged menisci.