Specific CD8+ T cell response immunotherapy for hepatocellular carcinoma and viral hepatitis

Figure 3 PD-1/PD-L1 blockade-induced restoration in vitro of hepatitis C virus-specific CD8⁺ T cells from a patient with chronic hepatitis C virus infection. A: FACScan^® dot-plots directly gated on ex vivo CD8⁺ T cells showing the PD-1 phenotype and the interferon (IFN)-γ secretion of HCV-NS3₁₄₀₆-pentamer-binding CD8⁺ T cells from a patient with chronic HCV infection and a patient who was able to resolve the infection; B: FACScan^® dot-plots showing the frequency of HCV-NS3₁₄₀₆-pentamer-binding CD8⁺ T cells after a 10-d specific in vitro challenge in the presence and absence of anti-PD-L1 to block the interaction between PD-1 and its ligand in the patients from (A) with chronic HCV infection and who resolved the infection; PD-1 expression on gated HCV-NS3₁₄₀₆-pentamer-binding CD8⁺ T cells after expansion is also shown. ALT: Alanine aminotransferase; HCV: Hepatitis C virus.