The relative abundance and proliferation of Tregs is diminished in the CNS of PACAP KO and the ratio of Teff to Tregs is enhanced.

<p>Panel <b>A</b> indicates the percentages of CD4⁺ cells in the CNS that were Tregs (CD4⁺CD25⁺Foxp3⁺) in WT and PACAP KO mice on days 0 (ND = non detectable), 14 and 20 days after EAE induction. Panel <b>B</b> reports the ratio Teff/Treg (calculated as the % of CD4⁺CD25⁺ cells that are Fox3^−/% of CD4⁺CD25⁺ cells that are Foxp3⁺). Panel <b>C</b> indicates, the percentage of CD4⁺CD25⁺Foxp3⁺ Tregs that are proliferating as determined by co-expression with the Ki67 antibody (C). Values represented are mean ± SEM. One experiment representative of three (n = 6 each) is shown. Student’s <i>t</i>-test *<i>P</i><0.05; **<i>P</i><0.01. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061200#pone.0061200.s006" target="_blank">Fig. S6</a> for representative FACS plots and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061200#pone.0061200.s007" target="_blank">Fig. S7</a> for determinations of total number of cells, % of total cells that are Tregs, and total numbers of Tregs during the course of EAE in the CNS of PACAP KO vs. WT mice.