Early immune-mediated response to ribavirin combined with IFN in patients with chronic hepatitis C.

Division of Gastroenterology and Hepatology, Department of Internal Medicine, Toho University School of Medicine, 6-11-1 Omorinishi, Otaku, Tokyo 143, Japan.
Hepatology Research (Impact Factor: 2.07). 02/2006; 34(1):15-22. DOI: 10.1016/j.hepres.2005.09.039
Source: PubMed

ABSTRACT This study was to investigate the immunomodulatory effects of ribavirin combined with interferon (IFN)-alpha 2b (R+IFN) compared with consensus IFN monotherapy (IFN-Con) in chronic hepatitis C (CHC) patients.
Thirty-four adult patients with biopsy-proven CHC, who were infected with HCV genotype 2a or 2b, were studied. A 24-week regimen of IFN-alpha 2b (6MU daily for 2 weeks followed by 6MU tiw for 22 weeks) and ribavirin (600-800mg/day for 24 weeks) was given to 17 patients. The other 17 patients were treated with a 24-week regimen of IFN-Con (18MU daily for 2 weeks followed by 18MU tiw for 22 weeks). Flow cytometric determination of cytoplasmic IFN-gamma and IL-4 expression in peripheral blood CD4+ T cells was performed, and the percentage of IFN-gamma+ and IL-4- (Th1), IFN-gamma- and IL-4+ (Th2) cells were calculated before and 3, 7, 14, and 28 days after the start of therapy.
In the R+IFN group, the percentage of Th1 cell peaked on day 3, and then decreased to near baseline by day 14, while the percentage of Th2 cell did not change. In the IFN-Con group, the percentage of Th1 cell peaked on day 14 and the percentage of Th2 cell peaked on day 3, and then decreased to near baseline by day 14.
Our results suggest that ribavirin induces an early immune response by peripheral blood CD4+ T cells in CHC patients.

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