Natural Cartilage-Derived Scaffolds for 3D Mesenchymal Stem Cell Culture: Promoting Chondrogenesis and Modulating Secretome Composition

Introduction: The regenerative potential of stem cells lies in their secretome, a collection of signaling molecules whose composition is shaped by the cellular microenvironment and external stimuli. To enhance cartilage regeneration, a 3D culture system using a natural cartilage scaffold has been developed to create a more chondrogenic secretome. This study investigates the chondrogenic differentiation of mesenchymal stem cells (MSCs) cultured in a decellularized bovine cartilage scaffold and analyzes the resulting secretome's composition. Methods: This study employed a randomized time series design to examine MSCs chondrogenic differentiation. A control group was cultured in standard 2D conditions, while two experimental groups were cultured in either 2D medium supplemented with chondrocyte differentiation medium (positive control) or a 3D decellularized bovine cartilage scaffold. The study hypothesized that the 3D culture would promote chondrogenesis at least as effectively as the positive control. Key chondrogenic markers were evaluated at various time points. Results: Statistical analysis revealed significant differences in marker expression between the experimental and control groups. SOX-9 and aggrecan were elevated in both experimental groups. The 3D group showed higher RUNX-2 expression and the highest Coll-2 expression at later time points. Additionally, growth factor analysis showed the 3D group had the highest levels of IGF-1 and FGF-2 towards the end of the study. Conclusion: 3D culture of MSCs in a bovine cartilage scaffold enhances chondrogenic differentiation and produces a secretome with comparable chondrogenic potential to traditional 2D culture with differentiation medium, suggesting its promise for cartilage regeneration.