Arterial calcification: Finger-pointing at resident and circulating stem cells

Figure 1 Carotid artery calcifications, hematoxylin and eosin staining. A: Sheet-like calcifications; B: Osteocytes are visible within the bone lacunae-like mature structure in development with lamellar bone. L: Lumen; FC: Fibrous cap; Arrowhead: Ossification; O: Osteocytes.

Figure 2 Osteoclasts-like giant cells admixed with inflammatory infiltrate. Arrows point osteoblast cells.

Figure 3 Osterix and osteocalcin expression in carotid plaques. A: Osterix immunohistochemistry (IHC) positivity in vessels single-label immunofluorescence micrographs representing Osterix (red) is also seen in the nucleus of endothelial cells of a single vessel; B: In the carotid endothelium layer, nuclei (blue) were counterstained with DAPI (4',6-diamidino-2-phenylindole); C: Cytoplasmic and extracellular matrix osteocalcin IHC pattern.

Figure 4 Scanning electronic microscopy. Budding process in vascular wall-resident multipotent stem cells in vitro.