Flow cytometric analysis of CNS-infiltrating T cells in MOG_35-55-immunized wild-type versus α4^−/− mice at the peak of EAE. Wild-type and α4^−/− mice were immunized with MOG_35-55 plus CFA and, at the peak of disease, cerebrum and spinal cord were analyzed separately. (A) Fraction and cytokine profile of CNS-infiltrating CD3⁺CD4⁺ T cells. Numbers indicate percentages of CD4⁺ T cells among live mononuclear cells (top row) or percentages of cytokine-positive cells within the CD3⁺CD4⁺ T cell compartment (bottom row, representative of five independent experiments). (B) Absolute number of CD4⁺ T cells within the brain (top row, left) or spinal cord (top row, right) of wild-type or α4^−/− EAE mice. In the bottom row, absolute numbers of IFN-γ, IL-17, or IFN-γ/IL-17 double-positive CD4⁺ T cells recovered from the brain or spinal cord of wild-type versus α4^−/− mice are depicted (means + SD, n = 5). (C) CD3⁺CD4⁺ T cells were highly purified by FACS sorting from supraspinal parts of the CNS (brain, i.e. brain stem, cerebellum, and cerebrum) of MOG_35-55-immunized wild-type or α4^−/− mice at the peak of disease. Fold change in relative abundance of Cxcr3, Ccr5, Ccr2, Ccr6, Il23r, Il1r1, and IL-22 mRNA in α4^−/− versus wild-type control mice (log scale, means + SD, n = 3).