IgE alone up-regulates FcεRI expression on rat mast cells.

Mast cells were incubated with IgE at 1 µg/mL (white bars) and 5 µg/mL (black bars) or without IgE (control FcεRI expression on native mast cells referred to as 100%) for 1, 6 and 24 h. Surface FcεRI expression was analyzed by flow cytometry using mouse anti-rat FcεRI primary antibodies (10 µg/mL) and FITC-labeled goat anti-mouse secondary antibodies (5 µg/mL) (A). Representative flow cytometry histogram showing FcεRI expression on native mast cells as well as on mast cells treated with 5 µg/mL for 1 h (B). Results are presented as the mean ± SEM of four independent experiments (n = 4). *p