Fig. 3.

In vivo depletion of CD25⁺ Treg exacerbates clinical signs of EAE and potentiates EAE induction with a subagonist APL. B10PL (A and C) and B10PLxSJL (B and D) mice were injected i.p. with 1 mg of PC61 (filled symbols) or isotype control Ab (MAC49; open symbols). EAE was induced by immunization 2 or 3 days later with 200 μg of WT Ac1-9 (A and B) or Met-3 APL (C and D). For B10.PL mice (A and C), data were pooled from two experiments (n = 11). For B10.PLxSJL mice, data were pooled from three (n = 16; B) or four (n = 23-28; D) experiments. Mortality rates in response to WT peptide for PC61^- and Mac49-treated mice, respectively, were 3/11 and 0/11 (A) and 9/16 and 4/16 (B) (with a disease incidence of 91-100% for each group). The numbers in C and D indicate the disease incidence in each group. PC61 treatment led to a significant increase in cumulative disease scores in each case (P < 0.0001, one-tailed Mann-Whitney U test), and it resulted in a significant increase in disease incidence in response to subagonist APL (C and D) (P < 0.05, one-tailed Fisher's exact test).