Figure 4

Morphological analysis of the primary human Intestine Chip. (a) Representative immunofluorescence microscopic views from above of the intestinal epithelium grown on-chip for 12 days under fluid flow and cyclic strain showing the presence of a continuous brush border along the apical membranes of epithelial villi-like protrusions, which are juxtaposed in close proximity, as visualized by labeling of the brush border for F-actin (magenta) and for nuclei with DAPI (blue). (b) High magnification SEMs of the apical surface of the epithelium cultured on-chip showing a goblet cell (left) and absorptive enterocytes (right) with apical microvilli. (c–e) Immunofluorescence micrographs of the Intestine Chip showing polarized distribution of apical (F-actin,NHE3, villin) as well as basal (integrin β4) and basolateral (Na⁺/K⁺-ATPase,E-cadherin) proteins in the cross-sectional views of single villus-like structure all counterstained with DAPI (grey).(c) Integrin β4 (green) and F-actin (cyan). (d) Na⁺/K⁺-ATPase (green) and NHE3 (magenta), (e) Villin (magenta) and E-cadherin (green) (f) Confocal immunofluorescence micrographs showing the presence of apical intact tight junctions in the intestinal epithelium and underlying endothelium labeled with ZO-1 (magenta) as well as adherens junctions labeled for E-cadherin (yellow) and VE-cadherin (green); blue indicates DAPI-stained nuclei.