FIG. 4.

Analysis of the perforin contents of HBV- and HCV-specific CD8 cells ex vivo. (A) Dot plot analysis of perforin expression by HBV- and HCV-specific CD8 cells stained with anti-perforin monoclonal antibodies. Pt, patient. (B) Percentages of perforin-positive cells assessed ex vivo among the overall population of HBV- or HCV-specific CD8 lymphocytes. PBMC from patients with acute HBV and HCV infection were tested with HBV core 18-27, envelope (env) 335-343, and polymerase (pol) 575-583 and with HCV NS3 1073-1081, NS3 1406-1415, and NS4B 1992-2000 tetramers, respectively. The outcome of the disease (self-limited or chronic evolution) is indicated. ∗, frequency of tetramer-positive cells was <0.01% of CD8⁺ cells; nt, not tested. The percentages of perforin-positive cells in the two groups of patients were significantly different by Student's t test.