No abstract

Chondrogenic differentiation by mesenchymal progenitor cells (MPCs) is associated with cytokines such as transforming growth factor-beta 1 (TGF-PI) and dexamethasone. Extracellular matrix (ECM) also regulates the differentiation by MPCs. To define whether ECM plays a functional role in regulation of the chondrogenic differentiation by MPCs, an in vitro model was used. That model exposed to dexamethasone, recombinant human TGF-@l(rhTGF-@I) and collagens. The results showed that MPCs incorporated with dexamethasone and rhTGF-01 increased proliferation and expression of glycosaminoglycan (GAG) after 14 days. Type 11 collagen enhanced the GAG synthesis, but did not increase alkaline phosphatase (ALP) activity. When adding dexamethasone and rhTGF-PI MPCs increased mRNA expression of sox9. Incorporation with type I1 collagen, dexamethasone and rhTGF-Pl, MPCs induced mRNA expression of aggrecan and enhanced levels of type I1 collagen, and sox9 mRNA. In contrast, incorporation with type I collagen, dexamethasone and rhTGF-PI MPCs reduced levels of aggrecan, and sox9 mRNA, and showed no type I1 collagen mRNA. Altogether, these results indicate that type I and I1 collagen, in addition to the cytokine effect, may play a functional role in regulating of chondrogenic differentiation by MPCs.

No abstract

No abstract

No abstract