EAE is dependent on G-CSF signaling in hematopoietic cells. (A–E) WT (closed triangles, black bars) and Csf3r^−/− (open triangles, white bars) mice were actively immunized with MOG_35-55 in CFA. (A) Mean clinical scores (n = 25 WT, 21 Csf3r^−/− pooled from five independent experiments). (B) Representative paraffin sections of spinal cords stained with H&E. (C) Cell subsets recovered from spinal cords at peak of disease, shown as a percentage of total CD45⁺ cells. Cell types were defined as follows: neutrophil (CD45^hi, CD11b⁺, Ly6G⁺), monocyte (CD45^hi, CD11b⁺, CD11c⁻, Ly6G⁻), DC (CD45^hi, CD11b⁺, CD11c⁺), CD3⁺ (CD45^hi, CD3⁺), and microglia (CD45^mid CD11b⁺). Data are representative of two experiments (n ≥ 4 mice/group). (D and E) Circulating and splenic neutrophils (D) and monocytes (E) were enumerated by flow cytometry. Data were pooled from two independent experiments (n ≥ 5 per group). (F) MOG-specific cytokine production by draining lymph node cells measured by ELIspot. Data are representative of three experiments (n = 3–5 mice per group). In the experiment shown there were 2.4 × 10⁵ total cells/well. (G) Mean clinical scores of WT to WT (closed triangles, n = 10) or Csf3r^−/− to WT (open triangles, n = 9) bone marrow chimeric mice after active immunization with MOG_35-55 in CFA. Data are representative of three experiments. All graphs indicate means; error bars denote SEM. *, P < 0.05; **, P < 0.01; ***, P < 0.001. Bars, 100 µm.