PD-L1 costimulates the CD8 T cell response to LM infection.

<p>A, OVA_257–264/K^b+ splenic CD8 T cell population seven days after VSV-OVA infection from mice treated with IgG isotype control, anti-PD-1 (RMP1-14), or anti-PD-L1 (10F.9G2). B, (Top panel) Representative dot-plot of the CD8 T cell response from control or anti-PD-L1 treated mice eight days after infection. (Bottom panel) Compiled data showing the total numbers of OVA_257–264/K^b+ splenic CD8 T cells eight days after LM-OVA infection from mice treated with IgG isotype control, anti-PD-1(RMP1-14), anti-PD-L1(10F.9G2), or anti-PD-L2 (TY25). Data were analyzed by two-way ANOVA. (*p<0.05. ns, non significant). C, (Top panel) Representative dot-plot of the splenic CD4 T cell response from control or anti-PD-L1 treated mice eight days after infection. (Bottom panel) Compiled data showing the total numbers of LLO_190–201/I–A^b+ CD4 T cells of the spleen from day 8 LM infected mice treated with anti-PD-L1 (10F.9G2) compared with IgG isotype control. Data were analyzed by Student's <i>t</i> test. Data are representative of three independent experiments with five mice per group.