Thymosin b4 Regulation, Expression and Function in Aortic Valve Interstitial Cells
Quan-Yi Li PhD, Peter L. Jones PhD, Robert P. Lafferty BA, Daniel Safer PhD, Robert J. Levy MD

In order to understand the mechanism of tenascin-C (TN-C) in the progression of calcific aortic valve stenosis, cDNA subtractive hybridization was used to search for downstream genes regulated by TN-C in sheep aortic valve interstitial cells. It was shown that thymosin b4, an actin-binding protein, is up-regulated by TN-C. Furthermore, it was observed that thymosin b4 can up-regulate matrix metalloproteinase-2 (MMP-2), a MMP specifically associated with calcific aortic stenosis, indicating that thymosin b4 may be involved in the progression of calcific aortic stenosis through a TN-C-mediated signal pathway.