Experimental study to construct the three-dimensional scaffold of rabbit cartilage-shedding cells and evaluate their compatibility with stem cells
Objective To prepare decellularized scaffolds from rabbit cartilage at various concentrations and assess their physicochemical properties and compatibility with stem cells to provide an experimental basis for cartilage repair.Methods Bone marrow mesenchymal stem cells(BMSCs)were cultured using the Percoll density gradient separation method,and this was followed by flow cytometric analysis and testing of their osteogenic and chondrogenic differentiation capabilities.Cartilage pieces were excised from rabbit knees and hip joints and subjected to physical crushing,repeated freeze-thaw cycles,and mixed enzymatic digestion for decellularization.To compare and observe the physicochemical properties of the decellularized scaffolds at different concentrations,three groups of scaffolds(labelwd A,B,and C)were designed with concentrations of 100%,50%and 30%,with three replicates each.Third-generation PKH26-labeled BMSCs were seeded onto optimally concentrated scaffolds and cultured for 1 week to observe cell growth.Results Flow cytometry detected BMSC surface antigens with positive expression of CD44 and CD90 and negative expression of CD45.Osteogenic induction stained with alizarin red showed red calcific nodules,and chondrogenic induction stained with alcian blue showed blue cartilaginous nodules.No apparent cell morphology was observed in the three groups of scaffolds stained with hematoxylin-eosin,and toluidine blue.There was a significant difference in DNA concentration between decellularized samples and non-decellularized scaffolds(P<0.05).The content of glycosaminoglycans was slightly lower than the normal values.Significant differences were observed between the three groups of scaffolds in terms of pore size,water absorption,porosity,tensile strength,and Young's modulus(P<0.05).After co-cultivation of stem cells with the scaffolds,cell adhesion was found to be good.Conclusions Percoll density gradient separation can obtain high-purity rabbit BMSCs,and the mixed decellularization method is superior.Group B scaffolds were the most suitable for tissue-engineered cartilage repair.BMSCs cultured in vitro grew well on Group B scaffolds.
bone marrow mesenchymal stem cellsorganizational engineeringcartilage decellularized scaffoldco-cultivation