新生儿IL-18对Th1/Th2类细胞免疫平衡的作用与HBV宫内感染相关性研究

目的:探讨新生儿IL-18对Th1/Th2类细胞免疫平衡的作用与HBV宫内感染的相关性。方法:选择HBsAg、HBeAg双阳性但肝功能正常孕产妇分娩的新生儿157例,以其中胎儿宫内感染21例为研究组,无宫内感染136例为对照组。用流式细胞仪检测两组脐血白细胞介素-18(IL-18)、γ-干扰素(IFN-γ)、白细胞介素-4(IL-4)的表达水平。结果:(1)研究组IL-18及IFN-γ表达水平明显低于对照组,差异有显著性(P<0.05;P<0.05);研究组IL-4表达水平百分数高于对照组,但差异无显著性(P>0.05);研究组IFN-γ/IL-4高于对照组,差异有显著性(P<0.05);(2)研究组IL-18与IFN-γ、IL-4、IFN-γ/IL-4均呈显著正相关(P均<0.05)。结论:IL-18是Th1/Th2网络平衡的更高层次的调控者;IL-18水平下调,导致新生儿Th1/Th2细胞因子比例下降,以致不利于HBV的清除,IL-18水平下调可能是HBV宫内感染的危险因素之一。

Relationship between the effects on immune balance of helper T cell 1,2 (Th1/Th2) by interleukin-18 (IL-18) level of newborns and hepatitis B virus intrauterine infection.

Objective:To study the relationship between the effects on immune balance of T helper cell 1,2(Th1/Th2)by interleukin-18(IL-18)level of newborns and hepatitis B virus infection.Methods:One hundred and fifty-seven full-term neonates born by HBsAg and HBeAg postive mothers whose liver function were normal were selected.The intrauterine infection group was consisted of 21 cases for neonates and the non-intrauterine infection group was consisted of 136 cases for neonates.The two groups of newborns were both detected for interleukin-18,interferon-γ,interleukin-4 of cord blood by flow cytometry.Results:(1)The percentage of IL-18,IFN-γ levels of cord blood in study group was significantly lower than that of control group(P<0.05);The mean cytokine IL-4 levels of cord blood in study group was higher than that of the control group(P>0.05).The ratio of the cord blood IFN-γ/IL-4 levels of the cord blood in study group was significantly higher than that of the control group(P<0.05);(2)The positive correlation existed between IL-18 and IFN-γ,IL-4,IFN-γ/IL-4 both in two groups.Conclusion:IL-18 regulated immune balance of Th1/Th2,and the decrease of the cord blood IL-18 maybe induce to the decrease of ratio of Th1/Th2 type cytokines in the cord blood.The imbalance of immune regulation of Th1/Th2 maybe the main mechanism of HBV intrauterine infection;HBV intrauterine infection is related to the decrease of IL-18.