OBJECTIVETo investigate the effect of IL-12 on IFN-gamma and IL-10 production of peripheral blood mononuclear cells (PBMC) in chronic hepatitis B virus infection patients during IFN-alpha treatment.

METHODSBefore and after IFN-alpha treatment of 3 months and 6 months, PBMC of 20 patients with chronic hepatitis B virus infection were collected and cultured in vitro in the culture fluid containing PHA (100 microg/ml), HBcAg (1 microg/ml), or HBeAg (1 microg/ml) for 48 h under the condition of the presence or absence of IL-12 (10 ng/ml). Then the levels of IFN-gamma and IL-10 were determined by ELISA.

RESULTSThere were 12 responders and 8 nonresponders to IFN-alpha treatment. In the responders, the enhancing effect of IL-12 on IFN-gamma production was significantly greater after IFN-alpha treatment than before the treatment. The production of IL-10 was suppressed in the presence of IL-12 after 3 months and 6 months of IFN-alpha treatment. In the same treatment time, the level of IFN-gamma in the presence of IL-12 was significantly higher than that in the absence of IL-12. To the nonresponders, the enhancing effect of IL-12 on IFN-gamma production was also significantly increased after IFN-alpha treatment. Moreover, in the same treatment time, the level of IFN-gamma in the presence of IL-12 was significantly higher than that in the absence of IL-12.

CONCLUSIONSThe enhancing effect of IL-12 on IFN-gamma production of PBMC in patients with chronic hepatitis B virus infection is increased during IFN-alpha treatment. IFN-alpha and IL-12 may enhance the efficacy for the treatment of chronic hepatitis B virus infection.