Figure 8.

Tolerance against MOG_35–55 inhibits neurological disease induced by the DTA-derived MOG-specific T cells. Tamoxifen-treated Plp1-CreER^T;ROSA26-eGFP-DTA mice at 32 weeks after injection were either tolerized against the MOG_35–55 peptide by a single i.v. treatment with MOG_35–55-PLG nanoparticles or injected with control OVA_323–339-PLG nanoparticles. (a) Motor defects (DTA + OVA_323–339-PLG compared to DTA + MOG_35–55-PLG: week 37, P = 0.0393; week 38, P = 0.0019) and (b) weight loss were assessed weekly between weeks 32 and 39 (DTA + OVA_323–339-PLG compared to DTA + MOG_35–55-PLG: week 36, P = 0.0281; week 37, P = 0.009; week 39, P = 0.0434). (c,d) At week 39 after injection, FACS analysis of the CNS (c) (CD45^hi, P < 0.0001; CD3⁺CD4⁺, P < 0.0001; CD3⁺CD4⁺Ki67⁺, P < 0.0001; CD3⁺CD4⁺Ki67⁺IFN-γ⁺, P < 0.0001; CD3⁺CD4⁺Ki67⁻IFN-γ⁺, P = 0.009; CD3⁺CD4⁺Ki67⁻IL-17⁺, P = 0.009) and spleens (d) was completed to determine the number and phenotype of the CD4⁺ T cells in these tissues. (e–g) CD4⁺ T cell responses to MOG_35–55 were assessed by culturing 1 × 10⁶ total splenocytes for 3 d with medium alone, anti-CD3 (1 µg/ml), OVA_323–339, MOG_35–55 or PLP_178–191 (10 µg/ml). The levels of secreted IFN-γ (e) (MOG_35–55 activation P < 0.0001), IL-17 (f) and cellular proliferation (g) (MOG_35–55 activation P < 0.0001) as determined by tritiated thymidine incorporation were assessed. One representative experiment of two is presented with n = 6 mice per group. The data are presented as the mean + s.e.m. *P < 0.05, **P < 0.01 and ***P < 0.001 for differences shown between the different groups. Two-way ANOVA with Bonferroni post hoc analysis.