Adoptive transfer of α4-deficient MOG_35-55-specific TCR transgenic T cells (2D2) into Rag1^−/− mice after in vitro polarization into Th1 or Th17 cells. Naive T cells from 2D2 × CD4 Cre × α4^flox/flox mice (α4^−/− 2D2) were differentiated into Th1 or Th17 cells in vitro and transferred into Rag1^−/− recipient mice. The host mice were followed clinically according to the classical EAE score (A) and according to an ataxia score (B). Means of clinical scores + SEM for classical and ataxic EAE are depicted (two-way ANOVA plus Bonferroni’s post-testing). (C) At the peak of disease, lymph nodes, spleens, spinal cords, and brains (i.e. brain stem, cerebellum, and cerebrum) were dissected. Mononuclear cells were isolated separately and analyzed by flow cytometry. Quantification of absolute numbers of α4-deficient 2D2 CD3⁺CD4⁺ T cells in lymph nodes and spleen (C, top row) and in spinal cord and brain (C, bottom row) reisolated from individual host mice (Student’s t test). Horizontal bars indicate mean.