Frequency of CD4^<b>+</b> T_CM and CD4^<b>+</b>T_EM cells producing IFN-γ upon recall with CSP peptides.

<p>PBMC were obtained at the indicated time points from RTS,S-immunized subjects and were incubated as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0020775#pone-0020775-g003" target="_blank">Fig. 3</a> with CSP peptides as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0020775#s2" target="_blank">Methods</a>. Cells were then analyzed as described in the legend to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0020775#pone-0020775-g001" target="_blank">Fig. 1</a>. The resulting values are plotted as the % of [A] IFN-γ producing CD4⁺ T_CM cells and [B] IFN-γ producing CD4⁺ T_E/EM cells for protected (closed symbol) and non-protected (open symbol) subjects. Statistically significant differences between pre-immune and post-vaccination time points are indicated at the top of the graph. Statistically significant differences between values for protected and non-protected subjects are as indicated within the body of the graph. *p<0.05; **p<0.01; ***p<0.001.