The percentages of CD8+ T lymphocytes expressing CD223 among chronic hepatitis B patients with high ALT and low DNA (Group I) and high ALT and high DNA (Group II) were significantly higher than the percentage of CD8+ T lymphocytes expressing CD223 in the HCs group (41.79 ± 16.03% and 41.98 ± 18.63% vs. 25.96 ± 16.27%, P = 0.013 and P = 0.004, respectively). This evidence concerns the gene LAG3 and chronic hepatitis B virus infection.