Fig. 4: SOX2⁺PHOX2B⁺ transitional cells are present in the human adrenal medulla.

A Representative image showing H&E and immunofluorescence staining for SOX2, PHOX2B and SOX10 in a 4-year-old human adrenal gland. The box shows one of 5 counting medullary regions in this sample. Full arrows indicate PHOX2B-positive cells, full arrowheads indicate SOX2⁺SOX10⁺ double-positive sustentacular glial cells, and full triangles indicate SOX2⁺SOX10⁺PHOX2B⁺ triple-positive glial cells. Scale bars in the adrenal gland and insets are 100 μm and 20 μm, respectively. B Representative image showing H&E and immunofluorescence staining for SOX2, PHOX2B and SOX10 in a 20-week-old human adrenal gland. The box shows one of 5 counting medullary regions in this sample. Full arrows indicate PHOX2B-positive cells, full arrowheads indicate SOX2⁺SOX10⁺ double-positive sustentacular glial cells, and full triangles indicate SOX2⁺SOX10⁺PHOX2B⁺ triple-positive glial cells. Scale bars in the adrenal gland and insets are 100 μm and 20 μm, respectively. C Percent-stacked bar plot for the ratios of PHOX2B positive cells (56.89% ± 0.51%, indicated by full arrow), SOX2⁺SOX10⁺ double-positive cells (9.90% ± 1.76%, indicated by full arrowhead) and SOX2⁺SOX10⁺PHOX2B⁺ triple-positive cells (1.60% ± 0.92%, indicated by full triangle) in cell number within all counting medullary regions (3 samples with 5 counting medullary regions each). Kruskal-Wallis test; adjusted P value from Dunn’s multiple comparisons test for PHOX2B⁺ vs SOX2⁺SOX10⁺ is 0.5391, for PHOX2B⁺ vs SOX2⁺SOX10⁺PHOX2B⁺ is 0.0219, and for SOX2⁺SOX10⁺ vs SOX2⁺SOX10⁺PHOX2B⁺ is 0.5391; n = 3. Data are presented as mean ± s.e.m. *, P value < 0.05.