Impairment of the intestinal epithelium barrier through alteration of proliferation and differentiation balance in alcohol use disorder

Figure 7 Epidermal growth factor receptor-mitogen-activated protein kinase signaling in duodenal biopsies. A: Immuhistofluorescence staining of pEGFR (red) which located in the crypt and villus in alcohol use disorder (AUD) and healthy subjects; B: Quantification of pEGFR⁺ cells in the transit-amplifying zone, normalized to the total number of transit-amplifying-zone cells, shows no significant difference between AUD patients and healthy subjects; C: Immunofluorescence staining of pERK, a downstream effector of the epidermal growth factor receptor-mitogen-activated protein kinase signaling pathway, reveals predominant expression in the lamina propria with only a very few pERK⁺ cells detected within the crypts. Scale bar (200 μm). Healthy (n = 3); AUD (n = 8). AUD: Alcohol use disorder; LYZ: Lysozyme; TA: Transit-amplifying.