Objective: To explore the possible relationship between cytokines (TNF-alpha, IFN-gamma, IL-4 and IL-10), which were expressed abnormal quantity in the peripheral blood to intrauterine HBV infectious children, gene single nucleotide polymorphism (SNP) and susceptibility to HBV intrauterine infection.
Methods: A cross sectional study on molecular epidemiology was carried out. The subjects were selected from outpatients of the hepatitis B vaccine special clinics of our hospital. According to intrant criteria, children under high risk of HBV intrauterine infection were divided into immuno-failure group (group I) and immuno-effective group (group II) while children without high risk were included in the control group. Four gene SNP sites of TNF-alpha-238, IFN-gamma + 874, IL-4-590 and IL-10-1082 region were determined by real-time quantitative fluorescent PCR.
Results: Significant differences of TNF-alpha-238 A allele frequency were found between group I and group II (chi(2) = 6.797, P < 0.05) as well as between group I and control group (chi(2) = 9.513, P < 0.05). No evident difference of TNF-alpha-238 A was found between group II and control group (chi(2) = 0.047, P > 0.05). Significant differences of IFN-gamma + 874 A allele frequency were found between group I and group II (chi(2) = 7.238, P < 0.05), and between group I and the controls (chi(2) = 5.199, P < 0.05) but no significant difference was found between group II and control group (chi(2) = 0.602, P > 0.05). Significant differences of IL-4-590 C/T allele frequency were not found between group I and group II (chi(2) = 0.632, P > 0.05), group I and control group (chi(2) = 0.584, P > 0.05), or between group II and control group (chi(2) = 0.004, P > 0.05) respectively. Significant differences of IL-10-1082 G allele frequency were found between group II and group I (chi(2) = 10.359, P < 0.001), and between group II and the controls (chi(2) = 35.418, P < 0.001), but not found between group I and control group (chi(2) = 1.759, P > 0.05).
Conclusion: This study suggested the possibility that TNF-alpha-238 A allele and IFN-gamma + 874 A allele were associated with HBV intrauterine infection. There was no evident relationship between IL-4-590 C/T allele SNP and susceptibility to HBV intrauterine infection, but the IL-10-1082 G allele seemed to be associated with preventive efficacy to HBV intrauterine infection.