Fig. 1
PLP-CD8 induce functional changes in DC. Five million CD8+ T cells reactive against the myelin peptide, PLP178-191 (PLP-CD8), or the control peptide, OVA323-339 (OVA-CD8), or PBS were adoptively transferred into wild-type recipient mice one day before inducing EAE with PLP178-191. A shows EAE scores (Mean ± SEM) of 3 groups of mice over 20 days post-EAE induction. Recipients of PBS or OVA-CD8 developed severe ascending paralysis while those of PLP-CD8 remained protected from EAE induction. (N = 5/group, Kruskal–Wallis test). B-C Splenic DC were isolated from PLP-CD8 recipients (PLP-CD8-DC) or OVA-CD8 recipients (OVA-CD8-DC) on day 12 post-EAE induction and cultured with CFSE-labelled CD4+ T cells from PLP-immunized mice at a 1:10 ratio (DC: CD4+) with rIL-2 (10 pg/ml) and increasing concentrations of PLP178-191 (0 to 50 µM) for 5 days. B CD4+ T cell proliferation (%CFSE-dilute CD4+) was plotted as a function of increasing peptide concentrations and was significantly higher with OVA-CD8-DC (N = 3, Two-way ANOVA with multiple comparisons). C The area under the curve (AUC) was calculated for the dose–response curves and data were normalized to OVA-CD8-DC. AUC for CD4.+ proliferation in response to increasing peptide concentrations was significantly lower with PLP-CD8-DC (N = 3, Student T-test). D-F PLP-CD8-DC and OVA-CD8-DC (250,000) isolated on days 3 and 13 post-EAE induction were stimulated with anti-CD40 antibody (100 µg/ml) for 48 h and the levels of IL-12p70 and IL-10 were measured in the supernatant using ELISA and normalized to OVA-CD8-DC. Normalized cytokine values on day 3 are shown in panel D on day 13 in panel E. Panel F shows the Mean ± SEM cytokine levels. Cytokine profile of both DC groups was similar on day 3 while PLP-CD8-DC produced lower levels of IL-12p70 and higher levels of IL-10 than OVA-CD8-DC on day 13 post-EAE induction (N = 3, student T-test) (ns = not significant, *p < 0.05, **p < 0.01)