PD-L1 upregulation by IFN-α/γ-mediated Stat1 suppresses anti-HBV T cell response
Fig 5
Anti-PD-1 mAb treatment enhances the HBV-specific T cell responses induced by gp96 therapeutic vaccine in HBV transgenic mice.
HBV transgenic mice were immunized with the therapeutic vaccine containing HBsAg, HBcAg, and gp96 adjuvant at wks 1, 2, and 4, and/or treated with anti-PD-1 mAb (n = 5 mice/group). Mice were sacrificed at wk 9 for immunological analysis. The gating strategy for CD4 + and CD8 + T cells in lymph nodes and splenic lymphocytes by flow cytometry(A). Flow cytometric analysis was performed to quantify IFNγ+CD8+ or IFNγ+CD4+ T cell populations in the liver (B) or spleen (D) of mice. For IFN-γ ELISPOT assay, lymphocytes from liver (C) or spleen (E) (5 × 105 cells/well) were stimulated with HBsAg/HBcAg (5 μg/ml each), or BSA as a negative control for background evaluation. Data are presented as the mean ± SD for five mice from two independent experiments. *P < 0.05, **P < 0.01, and ***P < 0.001 using t-tests.