NPM1 expression modulates chemokine secretion on LPS exposure in murine macrophages. (A) Mouse macrophages were obtained ex vivo from wild-type (WT) or npm^+/− mice treated for 4 days by M-CSF before exposure to LPS and measurement of cytokine gene expression by reverse transcription–quantitative PCR. (B) Wild-type and npm^+/− mice were injected intravenously with LPS (0.5 mg/mL). Ten minutes after injection, their behaviors were video recorded for 20 minutes, and spin-around movements were scored. (C) Plasma cytokine array analysis of wild-type and npm^+/− mice injected with LPS at indicated time. (D) The ratio between cytokine quantities detected in control and npm^+/− mouse plasma injected or not injected with LPS was quantified and normalized to untreated control mice. (E) Wild-type, npm^+/−, and tlr4-mutated transgenic mice were injected intravenously with LPS (0.5 mg/mL). Their peripheral blood was collected after 30 minutes and examined by CBA for IL-6 level measurement and by FlowCytomix for KC fold increase measurement. Mean ± SD of 5 mice per group, 3 independent experiments; ****P < .001). Co indicates control.