FIG. 1.

Limited proliferation of HCV-specific CD4⁺ and CD8⁺ T cells in HCV patients achieving SVR following late therapy (C-SVR) compared to patients who resolved following early IFN therapy (A-SVR) or who resolved spontaneously (SpR). Cumulative data from CFSE proliferation assays performed on the different patient groups are represented as stimulation indices (SI) in response to different HCV peptide pools in CD4⁺ (A) and CD8⁺ (B) T cells. *, P < 0.05; **, P < 0.01 (Mann-Whitney U test). PBMCs (2.5 × 10⁶) were stimulated with HCV peptide pools at 1 μg/ml of each peptide for 6 days. IL-2 was added at the end of day 3 at a concentration of 20 IU/ml. The dashed line represents the cutoff for positive responses (SI = 2).