TPT inhibits epidermal Langerhans cell migration from skin explants. The ear halves from groups of 5 mice were cultured in 24-well plates as described in “Materials and methods” (with 100 ng/mL murine MIP-3β) and contained 2.5 nM TPT or medium alone. (A) 48 hours later, epidermal sheets were prepared from the ear halves and immunolabeled with FITC–anti–I-A/I-E antibody. Epidermal sheets were observed and photographed under a fluorescence microscope (magnification, × 40). (B) FACS analysis of LC egress from cultured ear halves. Cells in culture medium of the ear halves were collected and stained with PE–anti-CD11c and resuspended in 0.3 mL PBS and analyzed on FACScan for 50 seconds. The data are representative of 3 independent experiments with similar results. Error bars indicate standard deviation.