Presence of NK1.1 cells in spleen of mouse treated with G-CSF. A B6D2F1 mouse was treated with G-CSF at 25 μg/kg/d for 14 days with a miniosmotic pump and splenocytes were stained with FITC-labeled anti-TCRαβ antibody (X-axis) and PE-labeled anti-NK1.1 antibody (Y-axis). Note the presence of comparable numbers of NK1.1⁺ cells in G-CSF–treated and untreated mice (Control).