Effects of TNF, TGFα, and SpA on epithelial junctions. A, staphylococcal transmigration across monolayers stimulated with Newman spa complemented with TNF, TGFα, or TNF + TGFα compared with the wild-type (WT) strain. Data are shown in n = 8, representative of two individual experiments. Error bars, S.D. B, z-sections of polarized monolayers following stimulation for 20 h. Green, S. aureus; red, phalloidin. Scale bars, 20 μm. C, epithelial permeability across 16HBE monolayers measured by quantifying fluorescein-conjugated molecular weight 3,000 dextran translocation following stimulation with purified SpA at concentrations shown. D, cells stained with phalloidin (red) or anti-ZO-1 (green) with co-localization of actin and ZO-1 appearing yellow (Merge). x-y sections at comparable apical levels are shown. Scale bars, 20 μm.