No statistical difference was found between the two methods (p > 0.05, paired, two-tailed Student’s t-tests), but HLA-A2-positive patients with chronic Hepatitis B displayed obviously higher frequencies of HBc18–27/HBs183–191-specific CD8+ T cells than the HLA-A2-negative patients or HLA-A2-positive healthy donors, who only presented background level of the AST cells (p < 0.0001, unpaired, two-tailed Student’s t-tests) (Fig. 7c). This evidence concerns the gene CD8A and chronic hepatitis B virus infection.