Induction of Cartilage Regeneration by Nanoparticles Loaded with Dentin Matrix Extracted Proteins

Due to the limited self-repair capacity of articular cartilage, tissue engineering has good application prospects for cartilage regeneration. Dentin contains several key growth factors involved in cartilage regeneration. However, it remains unknown whether dentin matrix extracted proteins (DMEP) can be utilized as a complex growth factor mixture to induce cartilage regeneration. In this work, we extracted DMEP from human dentin and improved the content and activity of chondrogenic-related growth factors in DMEP by alkaline conditioning. Afterward, mesoporous silica nanoparticles (MSNs) with particular physical and chemical properties were composed to selectively load and sustain the release of proteins in DMEP. MSN-DMEP promoted chondrogenic differentiation of rat bone marrow-derived mesenchymal stem cells with fewer growth factors than exogenously added transforming growth factor-β1 (TGF-β1). Therefore, MSN-DMEP may serve as a promising candidate for cartilage regeneration as an alternative to expensive synthetic growth factors. Impact statement Several growth factors embedded in dentin matrix could be involved in cartilage regeneration. This article reports that alkaline conditioning could improve the content and activity of chondrogenic-related growth factors in dentin matrix extracted proteins (DMEP). Mesoporous silica nanoparticles (MSNs) with particular physical and chemical properties performed well in loading and sustained releasing of proteins in DMEP. In vitro and in vivo studies suggest that MSN-DMEP could be a promising candidate for cartilage regeneration as an alternative to expensive synthetic growth factors.