Natural course of chronic hepatitis B is characterized by changing patterns of programmed death type-1 of CD8-positive T cells

Figure 1 Programmed death type-1 (PD-1) expression in total peripheral CD8+ T cells in the natural stages of chronic hepatitis B virus (HBV) infection. A: The dot plots showing the percentage of PD-1+ CD8+ T cells in different natural stages of chronic HBV infection patients and normal controls and the horizontal bars indicating the median percentage of positive PD-1 in CD8+ T cells; B: The dot plots showing the PD-1 mean fluorescence intensity (MFI) expression in total CD8+ T cells, and the horizontal bars indicating the median PD-1 MFI expression level in CD8+ T cells. NC: Normal control.

Figure 2 PD-1 expression levels in the total T cells in the immune clearance stage of chronic HBV infection and liver inflammatory groups. A: The dot plots showing the percentage of positive PD-1 in CD8+ T cells in high and low liver inflammatory groups; B: The dot plots showing the PD-1 MFI expression level in the total CD8+ T cells in high and low liver inflammatory groups; C: Positive correlation between PD-1 MFI expression and alanine aminotransferase (ALT) levels in CD8+ T cells; D: Positive PD-1 percentage and ALT level in CD8+ T cells.

Figure 3 Relation between PD-1 expression level in CD8+ T cells and CD8+ T-cell responses in the immune clearance stage of chronic HBV infection. A: Inverse relation between the percentage of perforin and PD-1 MFI in positive CD8+ T cells; B: Inverse relation between the percentage of granzyme B and PD-1 MFI in positive CD8+ T cells; C: No correlation between the percentages of granzyme B and PD-1 in positive CD8+ T cells; D: No significant correlation between the percentages of perforin and PD-1 in positive CD8+ T cells.

Figure 4 Effect of anti-PD-L1 antibody on the function of CD8+ T cells in the immune clearance stage of chronic HBV infection. A, B: Significant restoration of CD8+ T cell response after blockage of PD-1/PD-L1; C: Restoration of T-cell proliferation after blockage of PD-1/PD-L1.