Images of mouse epithelium 62 days after estradiol treatment. Panels A–H are representative images of the vaginal epithelium of ovariectomized mice; A, B were not treated with estradiol; C–H were taken on the indicated number of days after estradiol treatment. Panels I, J are from an ovary-intact mouse 62 days after saline treatment and 7 days after progesterone treatment; K, L are from ovary-intact mice 62 days after estradiol treatment and 7 days after progesterone. Black and white images are Cellvizio confocal micrographs showing the nature of the vaginal epithelial surface; color images are H&E crossectional histology micrographs showing epithelial layers and thickness. Panels A, B (controls) show the thin, simple, squamous epithelium of the vaginal tract in an ovariectomized mouse; approx 13 μm. Panels C, D show the estradiol-thickened, stratified epithelium with large, proliferating nuclei seven days after estradiol treatment; approx 37 μm. Panels E, F show the epithelium has returned to a thin, simple, squamous layer of cells 38 days after estradiol treatment; approx 16 μm. Panels G, I, K (day 62) show the epithelial thickness to be approx 16 μm, 39 μm and 39 μm, respectively; the effects of estradiol treatment have lapsed. The ovary-intact mice have been progesterone-primed to make them infection-permissive and the ovariectomized mouse’s thin vaginal epithelium is already very susceptible to infection. (N=5/group).