Figure 2.

Light and electron photomicrographs showing expression of CD23 on intestinal epithelial cells. Jejunal tissues for light microscopy were obtained from (a) a naive control rat or (b) an actively sensitized rat. Sections were cryofixed and stained with anti-CD23 antibody. Strong immunoreactivity for CD23 is demonstrated on epithelial cells in the section from the sensitized rat but not in the section from the control rat. ×40. (c) Immunoelectron photomicrograph of enterocyte microvilli from a HRP sensitized rat before HRP challenge demonstrating gold-labeled CD23 receptors on the microvillus membrane (bar = 200 nm). (d) After HRP challenge, endosomes containing HRP with several CD23 labels on the endosome membrane are visualized (bar = 100 nm). These photomicrographs are representative of those prepared from four rats per group.