Fig. 4From: T-bet expression in CD8+ T cells associated with chronic hepatitis B virus infectionIFN-γ and perforin levels in the HBV-specific CD8+ T cell population. a Mean level of IFN-γ produced by HBV-specific T cells. Error bars indicate SEM. b Mean level of Perforin levels produced by HBV-specific T cells. Error bars indicate SEM. *represents P < 0.05, **represents P < 0.01, ***represents P < 0.001, ns means no significant, by unpaired t testBack to article page