Fig. 4 |. PD-1⁺CD38^hi CD8⁺ T cells induced as a result of anti-PD-1 pretreatment are dysfunctional.

a,b, Frequency of CD40L⁺ or IFN-γ⁺ PD-1⁺CD38^hi cells in total CD8⁺ T cells (a) and in the PD-1⁺CD38^hi CD8⁺ T cell population (b). c,d, Frequencies of annexin V⁺ PD-1⁺CD38^hi cells in total (c) and antigen-specific (d) CD8⁺ T cells. e,f, Frequencies of CD62L⁺CD44⁺ (e) and CD62L⁻CD44⁺ (f) CD8⁺ T cells after various treatments as shown. Data at day 13 (a–d) and day 20 (e,f) post-TC-1 tumor implantation. Data are representative of two independent experiments. Each dot corresponds to one mouse with the indicated number of mice per group given in parentheses. The error bars indicate the s.e.m. For comparison purposes, an unpaired, one-tailed Student’s t-test was used. *P = 0.0462 (lower), *P = 0.0258 (upper), **P = 0.0052, ***P = 0.0004 (left panel); *P = 0.0148 (lower), *P = 0.0309 (middle), *P = 0.0382 (upper), **P = 0.002, ***P = 0.001 (right panel) (a); *P = 0.0372 (lower), *P = 0.0449 (middle), *P = 0.0225 (upper), ***P = 0.0006 (left panel); *P = 0.0104 (lower), *P = 0.0421 (upper), **P = 0.004 (right panel) (b); ***P = 0.001, ****P ≤ 0.0001 (c); *P = 0.05 (lower), *P = 0.0146 (upper) (d); *P = 0.0299 (lower), *P = 0.012 (upper) (e); *P = 0.0318 (left), *P = 0.0271 (f) (right). *P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001; ****P ≤ 0.0001.