Human turbinate mesenchymal stromal cells as a potential option for cartilage tissue engineering

To produce alternate cell sources for the regeneration of cartilage, human turbinate mesenchymal stromal cells (hTMSCs) were tested by culture for their differentiation potential in three-dimensional scaffolds with conventional chondrogenic ingredients. We also evaluated the effects of co-culture with human septal chondrocytes (hSCs) on the chondroinduction of hTMSCs. We isolated hTMSCs from discarded human inferior turbinate tissue. The expression of mesenchymal stem cell surface markers was assessed by fluorescence-activated cell sorting. hTMSCs were cultured in an open-cell polylactic acid sponge with TGF-β and IGF-1. hSCs were co-cultured with hTMSCs at a 1:1 ratio. Chondrogenic hTMSC differentiation and the efficiency of co-culture with hSCs were analyzed histologically by toluidine blue O staining. Cartilage-specific gene expression and matrix production were evaluated quantitatively by real-time PCR and Western blotting. Surface epitope analysis revealed that the hTMSCs were negative for CD14, CD19, CD34, and HLA-DR, and positive for CD29, CD73, and CD90. hTMSCs cultured in the OPLA scaffold showed high cell expansion and a chondroblastic phenotype, demonstrated by the expression of cartilage- specific genes. The chondroinduced hTMSCs exhibited much higher cartilage-specific matrix production and gene expression than characteristic of hSCs or a 1:1 co-culture of hTMSCs and hSCs. These findings indicate that hTMSCs may be redirected towards a chondrogenic phenotype by in vitro culture when cultured in three-dimensional scaffolds with growth factors such as TGF-β and IGF-1.