Differential response of the granulocyte-colony stimulation factor receptor (G-CSFR) target genes in response to G-CSF in B6.Sle2c2 and B6 leukocytes. (A) CD11b is upregulated in B6.Sle2c2 peripheral blood leukocytes (PBLs) compared to B6 (left panel). Human (hu)G-CSF (120 ug) injected on day (d)1 (arrow) induced a greater CD11b upregulation in B6.Sle2c2 than in B6 PBLs (middle panel, n = 4 per strain). The overlay histograms on the right show representative CD11b expression in B6 splenocytes at d0 (dash) and d2 (black), and in B6.Sle2c2 splenocytes at d0 (filled gray) and d2 (open gray). (B) Itgam and Mpo relative gene expression in bone marrow (BM) and spleen cells cultured for 8 h in medium alone and with 0.1 or 1.0 ug/ml hu-G-CSF. Filled bars represent B6 and open bars represent B6.Sle2c2 (n = 3 per group). In each graph, the data were normalized to the average of untreated B6 values. (C) Intracellular pSTAT3 staining in total CD11b+, GR1hi CD11b+ and GR1lo CD11b+ splenocytes (four mice per strain). The top row shows representative overlays of the B6 (open black) and Sle2c2 (open gray) histograms, with the filled silver histograms showing the isotype control. The graphs show mean and standard error of the mean with the significance value from the t-test (A and C) or the Bonferroni multiple comparison test (B) (*P < 0.05; **P < 0.01; ***P < 0.001).