Neutrophil-specific deletion of STIM2 protects against cytokine-mediated systemic inflammation. (A) Analysis of STIM1 and STIM2 protein expression in mice with neutrophil-specific deletion. Neutrophils were isolated from WT, Stim1^ΔPMN, Stim2^ΔPMN, Stim1/2^ΔPMN mice, and levels of STIM1 and STIM2 were determined by western blot. (Right) Quantitation of mean ± SEM from 2 to 3 experiments. (B) Functional analysis of calcium flux in bone marrow neutrophils from WT, Stim1^ΔPMN, and Stim2^ΔPMN mice. Cells were loaded with Indo-1 and calcium flux determined by flow cytometry. (C-E) WT, Stim1^ΔPMN, and Stim2^ΔPMN and Stim1/2^ΔPMN mice were injected with zymosan 500 mg/kg intraperitoneally and followed for survival (C) or sacrificed at 6 hours and the peritoneal lavage obtained for cell counts, identification of neutrophils by flow cytometry (D), and measurement of TNFα and IL-6 by ELISA (E). Survival data represent 7 to 9 mice per group. Cell counts and cytokine levels are representative of 2 independent experiments and expressed as mean ± SEM. *P < .05.