Abstract: Objective: To investigate the effects of hepatitis B virus (HBV) on the T lymphocytes and their subsets in different alanine aminetransferase(ALT) states,and to elucidate the immunological mechanism of ALT-based antiviral therapy for hepatitis B. Methods: A total of 363 patients with chronic hepatitis B were selected as the subjects. According to the ALT abnormalities, the patients were divided into ALT normal group (131 cases),normal ≤ ALT<2 times of upper limit group (110 cases),and ALT ≥ 2 times of upper limit group (122 cases).The patients in ALT ≥ 2 times of upper limit group were given entecavir and followed up for 24 weeks.The hepatitis B antigen antibody parameters were measured by chemiluminescence immunoassay analyzer,the liver function parameters were measured by automatic biochemical analyzer,the HBV loads were measured by quantitative PCR analyzer,the classification of T lymphocytes was detected by flow cytometry, and the levels of serum interleukin-2(IL-2),interferon-γ(IFN-γ),interleukin-4(IL-4) and interleukin-10(IL-10) of the patients were detected by enzyme-linked immunosorbent assay(ELISA) method.The influence of different HBV loads in the immunological indexes in various groups and the changes of virological and immunological indexes of the patients before and after antiviral therapy were detected. Results: In ALT normal group, there were no significant differences in the total number of T lymphocytes,the number of Th/i lymphocytes,the number of Ts/c lymphocytes and the serum IL-2,IFN-γ,IL-4,IL-10 levels of the patients with different loads of HBV(P>0.05).In ALT ≥ 2 times of upper limit group, with the increase of virus load,the total number of T lymphocytes and the number of Th/i lymphocytes were decreased(P<0.05),and the number of Ts/c lymphocytes was increased(P<0.05); the cytokines IL-2 and IFN-γ levels were increased(P<0.05),and the cytokines IL-4 and IL-10 levels were decreased(P<0.05).Compared with before treatment,24 weeks atfer entecavir treatment, the patient's HBV DNA was decreased significantly (P<0.05),the total number of T lymphocytes and the number of Th/i lymphocytes were increased(P<0.05), the number of Ts/c lymphocytes was decreased(P<0.05); the cytokines IL-2 and IFN-γ levels were decreased(P<0.05),and the cytokines IL-4 and IL-10 levels were increased(P<0.05). Conclusion: The influence of HBV on immune function is different in different ALT states. Therefore, antiviral therapy for the hepatitis B patients with ALT ≥ 2 times of upper limit can significantly change the immunological state of the patients.

Key words: chronic hepatitis B, hepatitis B virus, virus load, T lymphocyte, alanine aminetransferase