Interleukin-18 Promoter Polymorphism and Development of Antibodies to Surface Antigen of Hepatitis B Virus in Hemodialysis Patients

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.