Abstract
BACKGROUND/OBJECTIVE: Hepatitis B virus (HBV) infection is the leading risk factor for cirrhosis and hepatocellular carcinoma (HCC). The objective of this investigation was to assess the association between "Killer Cell Immunoglobulin-Like Receptor" (KIR) gene frequencies and chronic HBV infection. METHODS: Chronic HBV carriers and healthy patients were selected for this study. The viral load for HBV were performed, and SSP-PCR was used to characterize the frequencies of KIR genes. RESULTS: The study suggested that inhibitory genes KIR2DL2 (crude OR = 2.82; p < 0.001), KIR2DL3 (crude OR = 2.49; p < 0.001) and activator gene KIR2DS2 (crude OR = 3.95; p< 0.001) might be associated with chronic stages of HBV infection. Conversely the inhibitory genes KIR3DL1 (crude OR = 0.49; p = 0.0018) and KIR3DL2 (crude OR = 0.41; p = 0.005), the activator gene KIR2DS1 (crude OR = 0.48; p = 0.014) and the pseudo gene KIR2DP1 (crude OR = 0.49; p = 0.008) could be associated with immunity against HBV infection. Chronic HBV patients who are carriers for the KIR3DL3 gene (crude OR = 8; p = 0.048) were positive for HBeAg and patients who carried the KIR3DL2 gene (crude OR = 3.21; p = 0.012) had a high HBV viral load compared to the rest of the study population. CONCLUSION: Our data showed evidence of a correlation between the risk of developing chronic HBV infection and certain KIR gene frequencies and also show that KIR3DL1, KIR3DL2, KIR2DS1 might confer a protective status against chronic HBV infection.