CD4^+CD25^+调节性T细胞表达水平对Th1/Th2类细胞免疫平衡的作用及与HBV宫内感染的相关性

Effects of CD4^+CD25^+ Regulatory T Cells on Th1/Th2 Balance and Their Relationships to Hepatitis B Virus Intrauterine Infection

目的探讨孕妇外周血及新生儿脐血中CD4+CD25+调节性T细胞(CD4+CD25+Treg)表达水平对Th1/Th2类细胞免疫平衡的作用及与HBV宫内感染的相关性。方法选择HBsAg阳性但肝功能正常的单胎足月妊娠未临产孕妇101例及其新生儿101例,根据脐血的检验结果将8例发生HBV宫内感染的新生儿及其母亲纳入研究组(n=16),将93例未发生HBV宫内感染的新生儿及其母亲纳入对照组(n=186)。采用流式细胞仪检测CD4+CD25+Treg和ELISA法检测各组干扰素-r(IFN-γ)及白介素-4(IL-4)水平。结果研究组中孕妇外周血和新生儿脐血的IFN-γ及IFN-γ/IL-4均明显低于对照组(P<0.05);且IL-4及CD4+CD25+Treg占CD4+淋巴细胞百分比都明显高于对照组(P<0.05)。研究组和对照组中孕妇外周血及新生儿脐血的CD4+CD25+Treg与IFN-γ、IFN-γ/IL-4呈负相关(P<0.01,P<0.05),与IL-4呈正相关(P<0.01,P<0.05)。结论 HBV宫内感染时,孕妇和新生儿Th1型特异性反应降低而Th2型特异性反应增强,Th1/Th2间的细胞免疫失衡可能是促使HBV宫内感染的机制之一。HBV宫内感染与孕妇外周血和新生儿脐血中CD4+CD25+Treg的分泌水平升高有关,CD4+CD25+Treg水平的升高可能是发生HBV宫内感染的高危因素之一。

Objective To investigate the effects of maternal blood and neonatal cord blood CD4^＋ CD25^＋ regulatory T（Treg）cells on Th1/Th2 balance and their relationships to hepatitis B virus（HBV）intrauterine infection.Methods According to the results of umbilical cord blood tes-ting,101 HBsAg-positive women with singleton full term pregnancy and normal liver function and their newborns were divided into two groups：study group（8 newborns with HBV intrauterine in-fection and their mothers）and control group（93 newborns without HBV intrauterine infection and their mothers）.CD4^＋ CD2 5＋ Treg cells were detected by flow cytometry and IFN-γand IL-4 levels were measured by ELISA.Results Compared with control group,maternal blood and neo-natal cord blood levels of IFN-γand IFN-γ/IL-4 significantly decreased but IL-4 levels and per-centage of CD4^＋ CD25^＋ Treg cells accounting for CD4^＋ lymphocytes significantly increased in＆amp;nbsp;study group（P〈0.05）.The percentage of CD4^＋ CD25^＋ Treg cells were negatively correlated with levels of IFN-γand IFN-γ/IL-4,but positively correlated with levels of IL-4（P＆lt;0.01 or P〈0.05）.Conclusion Specific Th1 response decreases but Specific Th2 response increases in HBV intrauterine infection.Th1/Th2 imbalance is one of the possible mechanisms responsible for HBV intrauterine infection.In addition,HBV intrauterine infection is correlated with the increase in maternal blood and neonatal cord blood CD4^＋ CD25^＋ Treg cells,which may be a major risk fac-tor for HBV intrauterine infection.