Figure 5.

Stx2a induces E-cadherin expression in mesenchymal cells. (A) Cellular co-localization of vimentin and E-cadherin. HIOs were incubated for 27 hours with Stx2a. Serial cryosections were co-stained for DNA (4′,6-diamidino-2-phenylindole [DAPI], blue), vimentin (red) to identify mesenchymal cells, and E-cadherin (green) to detect epithelial cells (left, co-stained) or stained for DNA and vimentin (center), or DNA and E-cadherin (right). White circles indicate the region where cells were stained with both markers. Scale bar: 50 μm. Representative images of experiments performed in triplicate. (B) Isolated mesenchymal cells derived from mRuby2 E-cadherin HIOs were treated with Stx2a (30 ng) in 500 μL medium for 27 hours, and stained for vimentin (green), E-cadherin (blue), or mRuby2 (red). Representative bright-field images merged with indicated fluorescent stains of experiments performed in triplicate. Scale bar: 50 μm. (C and D). Fluorescence intensity at 27 hours was quantified using ImageJ software, and plotted as means ± SD, n = 3. Statistical significance was assessed using a 2-tailed, unpaired t test. (C) Quantification of mRuby2 expression in isolated mesenchymal cells. (D) Quantification of E-cadherin in isolated mesenchymal cells. L, lumen; M, mesenchyme.