Differential expression of cartilage and bone-related proteins in pediatric and adult diseased aortic valves

► An actively regulated disease process underlies pathological changes in AoVD. ► Interstitial cells in diseased AoV share traits of mesenchymal progenitor cells. ► Pediatric diseased AoVs do not calcify or express osteogenic genes. ► Osteogenic gene expression is evident in adult calcified diseased AoVs. ► Pediatric and adult diseased AoVs have shared progenitor gene expression.