FIGURE 8.

Most CXCR4-positive cells in the palatal osteogenic centers are not positive for Sox9. (A) Upper panel: Fluorescent immunohistochemical double-stained coronal palatal section for Sox9 (red) with CXCR4 (green), representative for the wt E15 and HO-2 KO E15 fetuses. Middle panel: Near the disintegrating MES only a few Sox9-CXCR4 double-positive stained cells (white arrow) were found. Green panel: In the osteogenic centers near the forming nasal septum clusters of Sox9 expressing cells together with CXCR4 expressing cells. Red panel: The osteogenic centers in the lateral parts of the fusing palate demonstrated clusters of Sox9 expressing cells near CXCR4 expressing cells. (B) Upper panel: Fluorescent histochemical double-stained coronal palatal section for Sox9 (red) with CXCR4 (green), representative for the wt CD1 E16 and wt CD1 SnMP E16 fetuses, e.g., wt CD1 SnMP E16. Middle panel: In the osteogenic centers in the central part of the fusing palate, almost no Sox9-CXCR4 double-positive stained cells were found. Green panel: Near the forming nasal septum clusters of CXCR4 expressing cells were found near CXCR4 positive cells. Also in the cartilage of the nasal septum CXCR4 positive cells were found close to Sox9 positive cells. Red panel: The osteogenic centers in the lateral parts of the fusing palate demonstrated clusters of Sox9 expressing cells near CXCR4 expressing cells.