Immunofluorescence staining of Egr-1. After IgE sensitization, mouse BMMCs from wild-type mice or Egr-1–deficient mice were either left untreated (no treatment) or stimulated with TNP-BSA (10 ng/mL) for various times. Cells were fixed, permeabilized, and then stained with anti–Egr-1 Abs or control rabbit serum. Alexa 594–conjugated goat anti–rabbit IgG F(ab′)2 was used as a secondary Ab. DAPI staining was used to visualize the nucleus of the cells. TNP stimulation induced a transient expression of Egr-1, which is localized in the nucleus of the cells. As a control, no Egr-1 staining was observed in BMMCs from Egr-1–deficient mice. Original magnification, × 40. Immunolabeled specimens were mounted in DAPI containing Vectashield (Vector Laboratories, Burlingame, CA). Cells were examined using a fluorescence microscope (Nikon E600; Nikon, Tokyo, Japan) equipped with a DMX1200 camera and a CFI Plan-Fluor DDL 40 ×/0.75 objective lens. Images were processed using Adobe Photoshop 5.0 (Adobe Systems, San Jose, CA).
