Hepatitis B Virus Genotype B and High Expression of Interferon Alpha Receptor β Subunit are Associated With Better Response to Pegylated Interferon Alpha 2a in Chinese Patients With Chronic Hepatitis B Infection

BACKGROUND: Hepatitis B virus (HBV) is one of leading causes of various hepatic diseases including acute and chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Hundreds of million people worldwide are infected by HBV, chronically. OBJECTIVES: This study in conducted to investigate the influence of Hepatitis B virus (HBV) genotypes and type I IFN-αreceptor β subunit (IFNAR2) expression in liver on response to treatment with pegylated IFN-α-2a (Peg-IFN-α-2a) for chronic hepatitis B infection. PATIENTS AND METHODS: In this study, 65 eligible patients with chronic hepatitis B disease were enrolled. HBV genotypes of these patients were analyzed by using PCR-RFLP of the surface gene of HBV. The expression of IFNAR2 in the liver was immune histochemically investigated using anti-IFNAR2 antibody. All immune histochemical slides were read semi-quantitatively by image analysis. Chronic hepatitis B patients were treated with Peg-IFN-α2a therapy for a 48-week period and followed up for 24 weeks. Baseline characteristics and sustained viral response (SVR) to Peg-IFN-α-2a therapy were evaluated. RESULTS: 55 % of patients exhibited HBV genotype B and 31.7 % patients exhibited HBV genotypes C infections. After treatment with Peg-IFN-α-2a, SVR was achieved in 66.7 % of patients with HBV genotype B and in 26.3 % of patients with HBV genotype C (P = 0.009). Semiquantitative and the image analysis indicated by gray level values revealed a higher IFNAR2 expression in the group with severe inflammation (P < 0.001). Patients’ high IFNAR2 protein expression had a significant impact on SVR to Peg-IFN-α-2a therapy (P = 0.028). CONCLUSIONS: HBV genotype B and high expression of IFNAR2 in the liver of chronic hepatitis B patients are closely associated with better response to Peg-IFN-α-2a therapy in chronic hepatitis B disease.