Changes in the Th1/Th2 ratio during a 24-week course of an interferon alpha-2b plus ribavirin combination therapy for patients with chronic hepatitis C.

BACKGROUND AND AIM

It has been reported that immunological factors, such as the T-helper cell (Th)1/Th2 ratio, play a part in the mechanisms for the antihepatitis C virus (HCV) effect of the interferon (IFN) alpha-2b plus ribavirin combination therapy. By using flow cytometry, we examined this ratio during a 24-week course of combination therapy for patients with chronic hepatitis C.

METHODS

We recruited 21 patients with chronic hepatitis C (16 males, five females, genotype 1b, 17 patients; genotype 2a or 2b, four patients) who had been treated by combination therapy. Flow cytometry was used to examine the Th1/Th2 ratio before and at the 4th and 24th week of therapy. Patients who were HCV-RNA negative 24 weeks after the treatment was completed were defined to show sustained virological response (SVR).

RESULTS

Among the 21 patients, 10 showed SVR, the overall SVR rate being 47.6%. Patients were classified into an 'increase group' (Th1/Th2 ratio at 4 or 24 weeks of therapy being higher than those before therapy) and a 'decrease group' (the ratio being lower than before therapy). After 24 weeks of therapy, the SVR rate was 66.7% for the Th2 'increase group' and 14.3% for the Th2 'decrease group'. The former showed a significantly higher SVR rate (P = 0.0361).

CONCLUSIONS

The significant changes in the Th2 level correlated with the therapeutic effect during the IFN alpha-2b plus ribavirin combination therapy. The increase of the Th2 level during therapy could be a predictor for achieving SVR.