Induction of chondrogenic differentiation in cultured fibroblasts isolated from the inferior turbinate

Objectives: To explore options of cell sources for regeneration of cartilage, turbinate fibroblasts were tested for their differentiation potential when cultured in three-dimensional scaffolds with growth factors and co-cultured with septal chondrocytes. Methods: Fibroblasts and chondrocytes were seeded on to an alginate sponge in different proportions and were stimulated with TGF-β1 and IGF-I. Chondrogenic differentiation of fibroblasts was assessed by histology including immunohistochemical staining, which was examined by reverse transcriptase polymerase chain reaction (RT-PCR). Results: Chondroid cells with extracellular matrices occupied the porous structures of alginate sponge and immunolocalizations for type II collagen became prominent at four weeks in culture. Expression of type II collagen and aggrecan mRNA were detected by RT-PCR. Co-culture of fibroblasts and chondrocytes showed comparable expansion of cells and extracellular matrix to culture of chondrocytes only. Conclusion: These findings suggest that human turbinate fibroblasts are apparently redirected toward chondrogenic phenotype by in vitro culture system under specific conditions. Co-culture of turbinate fibroblasts with septal chondrocytes would be an effective method to expand cartilage specific extracellular matrix.