Figure 3.

Distribution of apical polarity marker ZO-1 in acini depends on the substratum for 3D culture. A. Organization of the basoapical polarity axis in acini formed by S1 cells in 3D-Matrigel™ drip cultures as shown by immmunofluorescence staining of basal (collagen IV [green], α6-integrin [green]), lateral [beta-catenin [red] and desmoplakin 1,2 [green]), lateroapical [ZO-1 [red], and apical mucin-1 [green]) polarity markers. Nuclei are counterstained with DAPI (blue). Size bar, 5 μm. B. Histograms of the percentages of multicellular structures with apically localized ZO-1 (Additional Table S1 with P values - See Additional file 1) when S1 cells are cultured in the presence of chicken basal lamina (CBL) [36], PuraMatrix™, PuraMatrix™ and 20% laminin (PuraMatrix™ +20% L), PuraMatrix™ and 20% Matrigel™ (PuraMatrix™ + 20% MG), synthetic ECM (sECM-drip), synthetic ECM and 5% Matrigel™ drip (sECM + MG drip), monolayer on glass (Two-dimensional-2D), on glass + 5% Matrigel™ drip (High-throughput [HTP] drip) compared to their respective Matrigel™ controls. *P < 0.05; ***P < 0.001; ns = nonsignificant; ND = nondetected (no multicellular structures with apically located ZO-1).