Effects of cytokine and cytokine receptor gene variation on high anti-HB titers: Following up on Taiwan's neonatal hepatitis B immunization program

Background A significant percentage of Taiwanese neonatal HB immunization recipients have subsequently exhibited low anti-HB titers at non-protective or undetectable levels. Several mechanisms have been proposed to explain this phenomenon, including low vaccination responsiveness, deficient lymphocyte function, inappropriate antigen processing and presentation, and abnormal cytokine secretion. Methods To determine genetic influences resulting in high anti-HB titers, we divided a study cohort of 183 individuals into an anti-HBs ≥ 1000 mIU/mL group and a 10–1000 mIU/mL anti-HBs titer group. Chi-square tests were used to compare genotype and allelic frequencies between the two groups. Results Data from univariate and multivariate regression analyses of cytokine and cytokine receptor gene variants indicate (a) increased potential of high anti-HB titers in the presence of the TT genotype of the IL - 4 rs2243250 SNP (OR = 3.19; p = 0.012) and the AA genotype of the IL - 4R rs1805010 SNP (OR = 2.25; p = 0.048), and (b) individuals carrying the TT genotype of the IL - 4 rs2243250 SNP had anti-HB titers at levels that were almost twice as high as those in individuals carrying the CC genotype (478.8 mIU/mL and 290.3 mIU/mL, respectively; p = 0.033). Conclusion Genetic determinants, especially IL - 4 and IL - 4R , may contribute to high anti-HB titers in immune responses to HB vaccinations.