Changes in anti-idiotype antibodies against anti-HBs during recombinant interferon treatment of chronic hepatitis B.

Ibarra MZ, Porres JC, Bartolomé FJ, Escudero M, Quiroga JA, Carreño V.

Department of Gastroenterology, Fundacion Jimenez Diaz, Madrid, Spain.

To determine the possible changes in the presence and level of anti-idiotype (anti-Id) antibodies against anti-HBs induced by recombinant interferon (rIFN) therapy in chronic hepatitis B virus (HBV) infection, a study of patients under rIFN treatment has been carried out. A total of 62 (38 treated and 24 controls), HBeAg and HBV-DNA positive HBsAg carriers were tested serially for the presence of IgG and IgM anti-Id antibodies. According to serological evolution, treated patients were divided in responders (HBeAg and HBV-DNA became negative) (n = 18) and nonresponders (n = 20). Control patients were also classified as having spontaneous seroconversion (n = 11) and without changes (n = 13). Basally all patients had IgG and IgM anti-Id. At the end of the follow-up period (15th month), a significant decrease was observed in the percentage of cases positive to anti-Id among rIFN-responders (IgG, 67%, p less than 0.01; IgM, 44%, p less than 0.001). In contrast, only one nonresponder lost IgM anti-Id during the study. Among controls, only one with spontaneous loss of HBV-DNA and HBeAg clearance became negative to both IgG and IgM anti-Id. In addition, in the basal sample, the rIFN-responders had significantly lower anti-Id levels than the nonresponders (p less than 0.05). Similar results were obtained when comparing the controls with or without spontaneous response (p less than 0.05). Furthermore, a significant decrease in the anti-Id levels among the rIFN responders at the 9th month was detected (p less than 0.01). In summary, the anti-Id antibodies decreased significantly in patients who became HBV-DNA negative following rIFN administration. This result confirms the close relationship between HBV replication and the anti-idiotype against anti-HBs.