MEPE-Derived ASARM Peptide Inhibits Odontogenic Differentiation of Dental Pulp Stem Cells and Impairs Mineralization in Tooth Models of X-Linked Hypophosphatemia
Figure 2
Light and electron microscopy of the cells, matrix and mineral in 3D SHED cell cultures.
SHED cell cultures maintained in nonmineralizing (NM) or mineralizing (M) conditions in the absence or presence of 20 µM of either phosphorylated (p-ASARM) or nonphosphorylated (np-ASARM) ASARM peptide for 21 days were visualized by light microscopy and by scanning (SEM) and transmission (TEM) electron microscopy. A,B: SEM reveals SHEDs (arrows) well integrated into the collagen scaffold. Mineralization of the cultures appears as nodules within the collagen scaffold (arrowheads) only in the M and the M+np-ASARM conditions. Energy-dispersive X-ray spectroscopy (EDX) for compositional microanalysis of the nodules (performed at the white square) shows major spectral peaks for calcium (Ca) and phosphorus (P) with an acquired Ca/P ratio of 1.67+/−0.05 in both mineralizing conditions where nodules appeared. C: Light microscopy (left panel) and TEM (center and right panel) of the mineralized cultures (M and M+np-ASARM). Mineralized nodules (black box, left panel) are often in close proximity to the SHED cells, and consist of aggregates of multiple, smaller mineralization nodules (arrowheads) and occasional mineralized collagen fibrils (white box center panel, and right panel).