Role of KIR genes and genotypes in susceptibility to or protection against hepatitis B virus infection in a Turkish cohort

BACKGROUND Killer cell immunoglobulin-like receptors (KIRs) are a family of inhibitory and activating receptors expressed by natural killer (NK) cells and regulate NK cell activity in the innate response against viral infections. The aim of this study was to determine the possibility of KIR genes and genotypes as a candidate for susceptibility to or protection against chronic hepatitis B virus (HBV) infection or spontaneous remission of the infection in a Turkish cohort. MATERIAL AND METHODS The present study was carried out on 37 patients with chronic HBV infection, 36 patients in spontaneous remission of HBV infection, and 85 healthy subjects. Sequence-specific oligonucleotide probes analysis was used to investigate 16 KIR genes. All data were statistically analyzed by the Fisher exact test. RESULTS The rate of inhibitory KIR2DL3 (p=0.0) and 3DS1 (p=0.0) were higher in the healthy group than the group composed of chronic HBV patients and patients with spontaneous remission. There were no statistically significant differences between the rate of AA and Bx genotypes of chronic HBV patients and patients with spontaneous remission and the control group (p>0.05). CONCLUSIONS Our results suggest that KIR2DL3 and KIR3DS1 genes could be protector genes for HBV infection and they could be important immuno-genetic markers in determining antiviral immunity in the Turkish population.