FIGURE 2.

Palatal epithelium classification. (A) Coronal palatal section, e.g., HO-2 KO E15. (B) For each section the palatal epithelial layers were subdivided into three regions of interest according to morphological characteristics: (Inside) epithelium of the palatal shelves from the edge, including the MES, to half of the width of the shelves (in red); (Outside) epithelium of the lateral half of the palatal shelves (in blue); (Lateral nasal wall) epithelium of the lateral wall of the nasal cavity, this region is positioned outside the palatal shelves and served as a control region (in yellow). Immunoreactivity scoring scale: Semi-quantitative scoring of CXCL12 immunoreactivity within the epithelial regions according to the following scale: HIGH, immunoreactivity present in almost the entire epithelial region; MODERATE, immunoreactivity present only partially in the epithelial region; LOW, almost no immunoreactivity present in the epithelial region. Immunoreactivity scored for the three regions of interest in a CXCL12 immunostained section. (C) Inside region was scored as HIGH, in red. (D) Outside region was scored as MODERATE, in blue. Lateral nasal wall region was scored as LOW, in yellow.