Fig. 6.

The PD-1 and PD-L1 blockade efficiently restores proliferation (A), and the absence of PD-1 induces reduced levels of apoptosis in T cells obtained from T. cruzi-infected mice (B). (A) Spleen cells were obtained from naïve or infected mice (14 dpi), CFSE stained, and cultured in the presence of the described stimuli/treatment. After 72 h of culture, the levels of expression of CFSE were assessed in each case. The marker in each histogram represents the percentage of cells considered to be proliferating. (B) Spleen cells were collected from C57BL/6 (WT) mice or PD-1^−/− mice (21 dpi), and the frequency of cells stained for annexin V that were negative for 7AAD staining was determined by cytometry within the indicated gates. Asterisks denote P values of <0.005 by Student's t test compared to those of WT mice. The lines represent the mean values obtained from uninfected WT mice. Data are representative values obtained from three independent experiments.