Interleukin-18 promoter polymorphism and development of antibodies to surface antigen of hepatitis B virus in hemodialysis patients.

ABSTRACT

BACKGROUND: Interleukin (IL)-18 is involved in hepatitis B virus (HBV) clearance and augments antibodies against surface antigen of HBV (anti-HBsAg) production during DNA vaccination. The IL-18 -1297C>T (rs360719) polymorphism may modulate the IL-18 expression. AIM: To determine the potential association of IL-18 -1297C>T polymorphism with development of anti-HBsAg in hemodialysis (HD) patients. METHODS: The frequency of IL-18 -1297C>T alleles and genotypes was identified by polymerase chain reaction restriction fragment length polymorphism in 435 HD patients. Group 1 (n = 219) developed an anti-HBsAg titer >10 IU/l as a result of vaccination or HBV transmission. Group 2 (n = 216) included patients who did not develop an anti-HBsAg titer >10 IU/l in response to at least one full series of vaccination or HBV transmission. The significance of genotype frequency was tested using the Fisher exact test. RESULTS: In group 1, the frequencies of -1297CC, -1297CT and -1297TT genotypes were 7.3, 39.7 and 53.0%, respectively, and in group 2 they were 1.9, 42.1 and 56.0%, respectively. The odds ratio for CC versus CT + TT was 0.239 (95% CI 0.079-0.728, p = 0.010), and for CC versus TT it was 0.240 (95% CI 0.078-0.738, p = 0.009). CONCLUSION: In HD patients, the IL-18 -1297CC genotype may play a role in anti-HBsAg development in response to HBV surface antigen.