Figure 2. CX3CR1-deficient mice showed an increased accumulation of CD11c⁺ dendritic cells in CNS correlating with more severe CNS pathology.

Brain mononuclear cells isolated at peak of EAE disease from Cx3cr1^GFP/+/Ccr2^RFP/+ and Cx3cr1^GFP/GFP/Ccr2^RFP/+ were separated over Percoll gradients and analyzed by flow cytometry. A) Total number of brain mononuclear cells and CD45^Hi infiltrating cells. (B) CD45^Hi infiltrating cells were gated to quantify myeloid cell subsets based on expression of CD115, Ly6C and CD11c. Open bars: Cx3cr1^GFP/+/Ccr2^RFP/+ mice with normal receptor function; shaded bars: CX3CR1-deficient Cx3cr1^GFP/GFP/Ccr2^RFP/+ mice (* P <0.05). (C) CX3CR1-GFP (open bars) and CCR2-RFP (gray bars) fluorescence intensities in monocyte subsets were compared in Cx3cr1^GFP/+/Ccr2^RFP/+ mice (* P<0.05). Values are mean ± SEM. Results are representative of two similar experiments. Brain tissues were stained with anti-CD45 antibodies (brown staining) as a marker of global inflammation and counterstained with Nissl (D-F), anti-MBP antibodies to assess demyelination (G-I) and anti-calbindin antibodies to visualize cerebellar Purkinje cells (J-L) in Cx3cr1^–/– naïve (D, G, J), diseased WT (E, H and K) and Cx3cr1^–/– (F, I, and L) mice. Scale bars D-F: 100 μm, G-L: 50 μm. (M) Myelin immunoreactive area, *P=0.03 between WT naïve and WT-EAE groups, **P<0.0001 between WT-EAE and KO-EAE groups. (N) Calbidin positive cells per section were counted in 4 mice per group *P=0.04 between WT-EAE and KO-EAE groups.