Eosinophils express surface and intracellular toll-like receptors. (A) Eosinophils from the spleens of hypereosinophilic mice were identified by CCR3 expression and high side scatter and stained for TLR-3, TLR-4, and TLR-7. Dashed lines denote isotype control (and were similar to unstained cells); solid lines represent respective TLR antibody. To detect intracellular TLR expression, splenocytes were pretreated with saponin. (B) Summary of mean fluorescence intensity (MFI) of surface and intracellular TLR expression by splenic eosinophils. The mean of 3 independent experiments is shown. (C) Neutrophils (Neuts) and eosinophils (Eos) were identified in the lungs of hypereosinophilic mice by scatter properties (left panel) and Gr-1 expression (middle panel). Comparative MFI of TLR-7 expression on neutrophils (N) and eosinophils (E) is shown in the right panel. Data represent the mean plus or minus SEM (n = 3-8 mice per experimental group). *P < .05; **P < .01; ***P < .001.