Figure 6. Expression of miR-155 by CD4⁺ T cells is required for proper development of inflammatory T cells during EAE.

A. 5×10⁶ WT or Mir155^−/− CD4⁺ T cells from naïve mice were injected i.v. into Rag1^−/− recipients, EAE was induced with MOG_35–55 24 hours later, and disease was scored over a time course (n=5–6). Data represent two independent experiments. B. Mice were harvested and engraftment of CD3⁺CD4⁺ T cells was assayed by flow cytometry using splenocytes (top). Expression of IL-17A and IFN-γ by CD4⁺ cells in the spleens and LNs was assayed by intracellular staining followed by flow cytometry. A representative plot from the LNs is shown (bottom). C. The averages of 5–6 mice per group are shown graphically. D. Mir155^+/+ and Mir155^−/− mice were injected with 1×10⁷ WT CD45.1⁺CD4⁺ naïve T cells, and EAE was induced 24 hours later (n=5). Disease symptoms were scored over a time course. Data represent two independent experiments. E. Mice were harvested and CD4⁺ T cells in the brains were analyzed by flow cytometry to detect cells expressing CD45.1, IL-17A and IFN-γ. F. The average of 5 mice per group from (E.). Error bars represent +/−SEM and * denotes statistical significance with a p value of <0.05 according to a student’s two-tailed t-test. +/+ = Mir155^+/+; −/− = Mir155^−/−. See also Figure S4.