FIG. 5.

Virus-specific responses are suppressed by CD4⁺CD25⁺ T_reg cells in HCV patients compared to healthy individuals. (A) The ratio of the specific CD8⁺ T-cell increase following CD4⁺CD25⁺ T_reg cell depletion over PBMC alone of all patients studied. The EBV- and CMV-specific responses in healthy individuals are in the left column, the EBV- and CMV-specific responses in HCV-infected patients are in the middle column, and the HCV-specific responses in HCV-infected patients are in the right column. The horizontal line in each column represents the median. (B) Depletion of CD4⁺CD25⁺ T_reg cells enhances IFN-γ secretion by virus-specific CD8⁺ T-cell in HCV-infected patients. PBMC alone (PBMC) and following depletion of CD4⁺CD25⁺ T_reg cells (Depleted) were used in an IFN-γ ELIspot assay using a pool of three HCV peptides or (C) the EBV peptide.