Interstitial cells from dogs with naturally occurring myxomatous mitral valve disease undergo phenotype transformation.

Abstract

Two patterns of interstitial cell phenotype transformation were identified in dogs with myxomatous mitral valve disease, and both correlated with disease severity. Myofibroblast transformation characterized by positive staining for alpha-actin and desmin occurred in cellular clusters primarily in the lamina atrialis. Mesenchymal cell activation characterized by positive staining to non-muscle myosin occurred throughout the valve. The dog may be a natural model for studying the cell biology of progressive myxomatous valve disease.