Fig. 6

Histopathological and immunological examination of HBV-DNA-Pol transgenic mice. A Pattern diagram of HBV-DNA-Pol transgenic mice drawn by Figdraw. Specific expression of HBV-DNA-Pol in liver tissue using albumin as a promoter. B Elevated PD-L1 mRNA levels in liver tissues of HBV-DNA-Pol transgenic mice. RNA extracts of liver tissues from HBV-DNA-Pol transgenic mice or wild-type mice were harvested and analyzed for PD-L1 mRNA levels. GAPDH mRNAs were used as a control. In all statistical comparisons, three independent experiments were performed (mean ± S.D., n = 3, Student’s t-test). **P < 0.01. C, D Increased PD-L1 protein levels in liver tissues of HBV-DNA-Pol transgenic mice. C Extracts of liver tissues from HBV-DNA-Pol transgenic mice or wild-type mice were collected and subjected to Western blotting with anti-Flag, anti-PD-L1 and anti-GAPDH antibodies. D Liver tissues from HBV-DNA-Pol transgenic mice or wild-type mice were subjected to IHC staining with antibody against Flag and PD-L1. Representative images are displayed. Scale bar, 100 μm. E, F Impaired proliferation of CD4⁺ and CD8⁺ T cells in the spleen of HBV-DNA-Pol transgenic mice. E Immune cells isolated from the spleens of HBV-DNA-Pol transgenic mice or wild-type mice were stimulated for 48 h, proliferation rates of CD4⁺ and CD8⁺ T cells were measured by flow cytometry. F The results were plotted after quantitation. G, H Impaired activation of CD4⁺ and CD8⁺ T cells in the spleen of HBV-DNA-Pol transgenic mice. G Immune cells isolated from the spleens of HBV-DNA-Pol transgenic mice or wild-type mice were stimulated for 24 h, CD69 expression of CD4⁺ and CD8⁺ T cells were measured by flow cytometry. H The quantified results were plotted. I, J Impaired cytokine secretion of CD4⁺ T cells in the spleen of HBV-DNA-Pol transgenic mice. I Immune cells isolated from the spleens of HBV-DNA-Pol transgenic mice or wild-type mice were stimulated for 24 h, IFN-γ and TNF-a production of CD4⁺ T cells were measured by flow cytometry. J IFN-γ and TNF-a production was summarized. K, L Impaired cytokine secretion of CD8⁺ T cells in the spleen of HBV-DNA-Pol transgenic mice. K Immune cells isolated from the spleens of HBV-DNA-Pol transgenic mice or wild-type mice were stimulated for 24 h, IFN-γ and TNF-a production of CD8⁺ T cells were measured by flow cytometry. L IFN-γ and TNF-a production was summarized. In all statistical comparisons, three independent experiments were performed (mean ± S.D., n = 3, Student’s t-test). *P < 0.05, **P < 0.01, ***P < 0.001