Human epicardium: ultrastructural ancestry of mesothelium and mesenchymal cells.
The human sub-epicardial area contains an unexplored cellular population under a layer of mesothelial cells. Transmission electron microscopy revealed the existence of interstitial Cajal-like cells (ICLCs), isolated smooth muscle cells (iSMC) and mesenchymal cells besides other well-known cells. The presence of iSMC in the sub-epicardial space is quite unique and could explain why epicardial-derived cells isolated from human epicardium generate smooth muscle cells in culture. Mesenchymal cells, guided by ICLCs, were found migrating from sub-epicardial area in the mesothelial layer. These findings suggest that epithelial-mesenchymal transition is not a common process involved in cardiac regeneration in vivo.
Gherghiceanu
Mihaela
M
Victor Babes National Institute of Pathology, Bucharest, Romania.
Popescu
L M
LM
D002465:Cell Movement; D003599:Cytoskeleton / Q000648:ultrastructure; D004848:Epithelium / Q000648:ultrastructure*; D006801:Humans; D008648:Mesoderm / Q000166:cytology* / Q000648:ultrastructure*; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000648:ultrastructure; D010496:Pericardium / Q000166:cytology* / Q000648:ultrastructure*