Interferon Alpha Receptor 2 Expression by Peripheral Blood Monocytes in Patients with a High Viral Load of Hepatitis C Virus Genotype 1 Showing Substitution of Amino Acid 70 in the Core Region

Department of Internal Medicine, Division of Gastroenterology and Hepatology, Toho University School of Medicine, Faculty of Medicine, Tokyo, Japan. iskoji377 @
Intervirology (Impact Factor: 1.77). 12/2009; 53(2):105-10. DOI: 10.1159/000264200
Source: PubMed

ABSTRACT When patients with chronic hepatitis C (CHC) are treated with interferon (IFN)-based therapy, achieving serum HCV-RNA negativity by week 12 (early viral response, EVR) is an important predictor of a sustained virologic response. The aim of this study was to clarify whether changes in IFN-alpha receptor 2 (IFNAR-2) expression by peripheral blood monocytes (Mo) and the EVR rate differed between patients with genotype 1b and a high viral load showing substitution of amino acid 70 in the core region of HCV (mutant, n = 20) and patients without this substitution (wild, n = 23). Patients and
Forty-three CHC patients were studied, and received pegylated IFN plus ribavirin. IFNAR-2 expression by Mo was determined using flow cytometry to measure the mean fluorescence intensity (MFI) before and up to 28 days after starting therapy.
The EVR rate of the mutant group was significantly lower than that of the wild group (35 vs.70%). The MFI of Mo was significantly higher in the wild group than in the mutant group before and also 3, 7, and 28 days after starting therapy.
Mutation of HCV was related to lower IFNAR-2 expression by Mo before and after starting therapy.

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