Regional specific tunable meniscus decellularized extracellular matrix (MdECM) reinforced bioink promotes anistropic meniscus regeneration

The healing of meniscus injuries poses a significant challenge, as prolonged failure to heal can lead to osteoarthritis, which presents a therapeutic dilemma in the field of sports medicine. Decellularized extracellular matrix (MdECM) derived from natural meniscus, and the incorporated growth factors have been used for potential fibrochondrocyte induction and meniscus regeneration. However, homogeneous MdECM is difficult to achieve region-specific biomimetic microenvironment for tissue regeneration. In this study, we successfully prepared a region-specific MdECM, which were then mixed with an ultraviolet responsible Gelatin Methacryloyl (GelMA)/hyaluronic acid Methacryloy (HAMA) hydrogel incorporated with bioactive factors, faciliatated a functional region-specific bioink. The 3D printed scaffold by anistropic MdECM and zonally designed microstructure could promote chondrogenic differentiation of inner region cells and fibrochondrogenic differentiation of outer zone cell, ultimately enhanced anisotropic meniscus regeneration and cartilage protection.