IFN-?– and IL-10–expressing virus epitope-specific Foxp3(+) T reg cells in the central nervous system during encephalomyelitis

Zhao, Jingxian; Zhao, Jincun; Fett, Craig; Trandem, Kathryn; Fleming, Erica; Perlman, Stanley

To determine whether M133-specific T reg cells were immunosuppressive, we isolated GFP + and GFP  CD4 T cells 2-infected B6 mice were treated with BFA or vehicle at 6 d after infection. After 6 h, CNS-derived lymphocytes were analyzed for IFN- expression. Plots shown were gated on CD4 T cells. Data are representative of six mice in two independent experiments. 5.1 ± 0.5 and 4.6 ± 0.3% of Foxp3  and Foxp3 + cells, respectively, expressed IFN- after in vivo BFA treatment. (F) IFN- is expressed at higher levels in effector CD4 T cells than in T reg cells after peptide M133 + S358 stimulation (data from 10 single or pooled brain samples analyzed at 7, 14, or 28 d after infection are combined) or after in vivo BFA treatment (six mice in two independent experiments). MFI, mean fluorescence intensity. Error bars in C, D, and F indicate mean ± SEM. ramers, we detected 163 ± 10 Foxp3  and 25 ± 2 Foxp3 + M133-specific CD4 T cells per three naive Foxp3 gfp mice (n = 3; Fig. 5 A) . To confirm these results in mice with a higher M133-specific precursor frequency, we developed Rg mice expressing an M133-specific T cell receptor, as described in Materials and methods (M133 TCR Rg). 0.2-5% of splenic CD4 T cells were M133 specific in uninfected M133 TCR Rg mice and, of these cells, 0.5-1% were Foxp3 + (Fig. 5 C) .