Cardiac valve interstitial cells: regulator of valve structure and function.

Cardiac valve interstitial cell tissue is present throughout the valve. The molecular biology of this cell type is not well known. The purpose of this review is to present our current understanding of the structure and function of valvular interstitial cells and to describe experimental approaches available to study the structure and regulation of interstitial cell function and the interaction of interstitial cells with the valve matrix and with the surface endocardial endothelial cells. Data available to date suggest that valvular interstitial cells are contractile, have some of the characteristic features of smooth-muscle cells, communicate with each other, secrete valvular matrix, regulate repair processes following valve injury, and exhibit heterogeneous phenotypes. Further studies are required to understand the regulation of structure and function of these cells in both health and disease. This information will indeed be useful in preventing valvular disease, in improving the design of therapeutic surgical valve reconstruction, and in designing prosthetic valves.