Figure 5. Both hFcεRI and mFcγRIV engagement by IgE ICs induces TNF-α secretion by peritoneal macrophages.

(A) Density plots show the binding of indicated mAbs to white blood cells from WT and hFcεRI^Tg transgenic mice. Histograms show the binding of anti-hFcεRI mAb to cell populations defined by 5 gates from the density plots of blood cells from hFcεRI^Tg (open black) or WT (solid gray) mice. (B) Indicated mice were injected intravenously with 9E9 or irrelevant hamster IgG 1 day before recovery of thioglycolate-elicited macrophages. The cells were assayed for TNF-α secretion by ELISA following incubation on IgE-, Ag-, or IgE^b IC (C48-2^b)–coated wells. All reagents were treated with Polymyxin B. Mean ± SD of triplicates are represented. Significant differences between cells triggered by IgE^b ICs are indicated (**P < 0.001; Student’s t test). The horizontal gray line represents background TNF-α levels. Data are representative of 3 (A) and 2 (B) independent experiments.