Lm rapidly crosses the epithelium of iFABP-hEcad transgenic mice in an InlA-dependent manner. (A) Intestinal tissue of iFABP-hEcad transgenic mice was fixed, permeabilized, and stained for F-actin and hEcad. A three-dimensional reconstruction of an intestinal villus is shown. (B) Three-dimensional reconstruction of an intestinal villus of iFABP-hEcad transgenic mouse infected with 109 Lm for 45 min and stained for hEcad and nuclei. (C) Optical sections and insets show Lm (asterisks) interacting with intestinal villus along its length (z in micrometers corresponds to distance from villus tip). Insets are a magnification of Lm (indicated by asterisks) interacting with intestinal villus epithelial cells or inside the lamina propria. Bars, 10 µm. (D) Quantification of Lm associated with intestinal villus (***, P < 0.001, as assessed by two-way analysis of variance and Tukey adjustment). Error bars indicate SD. n = 10 villi from three mice. (E, left) Longitudinal section of a villus on which planes along its z axis are depicted. (right) Quantification of Lm localized on the villus surface, in epithelial cells, or in the lamina propria along the z axis of intestinal villi. n = 10 villi from three mice. Pictures are representative of three mice.
