ABC-transporter localization. A: ABCC3, B: ABCC4, and C: ABCC5. Yellow arrows indicate the basolateral staining of ABCC3 in coloumnar epithelial cells and goblet cells. White arrows indicate the localization of ABCC4 in basolateral and perinuclear membranes of goblet cells, and black arrows indicate the basolateral staining of ABCC5 in columnar epithelial cells. D-E: Negative control images of staining with secondary antibody from goat (D) and rabbit (E). No immunohistochemical coloring was obtained for the ABCB1 transporter.