干扰素调节因子4在母胎界面的表达特点及作用

Expression and significance of interferon-regulatory factor 4 at fetomaternal-interface

目的 研究干扰素调节因子4（IRF4）在母胎界面的表达及作用.方法 以BALB/c雌雄鼠构建妊娠模型,免疫组化检测孕14.5d的子宫胎盘组织中IRF4蛋白定位表达.同时,获取未孕及孕4.5、8.5、12.5、16.5 d的脾脏和子宫胎盘组织,以实时定量PCR（qPCR）检测IRF4和RORγt mRNA水平,并分析两者的相关性;将CBA/J雌鼠和DBA/2J雄鼠交配构建自然流产小鼠模型,以与BALB/c雄鼠交配的CBA/J雌鼠为正常妊娠对照,qPCR和Western blotting分析两组小鼠母胎界面IRF4、RORγt和IL-17的表达差异.结果 IRF4主要表达于母胎界面的淋巴细胞;妊娠过程中,母胎界面的IRF4水平呈动态变化,孕4.5 d达到高峰（1.92±0.12）,余妊娠期均明显低于未孕状态（孕8.5、12.5、16.5 d与未孕时的表达值分别为：0.25±0.03、0.03±0.01、0.10±0.005和1.00±0.04;P＜0.05）,且与RORγt的水平呈正相关（r2=0.6968,P＜0.05）;自然流产组IRF4的mRNA和蛋白水平均明显高于正常妊娠对照组[（1.41±0.04）比（1.00±0.12）,P＜0.05],同时自然流产组RORγt和IL-17的mRNA水平也更高（RORγt：（2.01 ±0.03）比（1.00±0.14）;IL-17：（2.69±0.20）比（1.00±0.09）,均P＜0.05）.结论 IRF4可能通过RORγt作用于Th17细胞的分化和功能,参与母胎免疫调控,影响妊娠结局.

bjective To investigate the expression and significance at interferon-regulatory factor 4 （IRF4） at fetomaternal-interface in pregnancy and abortion.Methods Pregnancy models were established in BALB/c mice.Immunohistochemistry was used to detect the IRF4 protein expression in uterine placenta tissue at 14.5 days of gestation.The spleen and uterine placenta tissues were harvested from unpregnant mice and those at 4.5,8.5,12.5 and 16.5 days of pregnancy,and were measured for IRF4 and RORγt mRNA levels by using real-time quantitative PCR （qPCR）.The correlation between IRF4 and RORγt mRNA levels was analyzed.A spontaneous abortion mouse model was established by mating female CBA/J mice and male DBA/2J mice,and a normal pregnancy control by mating female CAB/J mice with male BALB/c mice.qPCR and Western blotting were used to analyze the expression differences in IRF4,RORγt and IL-17 at the fetomaternal interface.Results IRF4 was mainly expressed in the lymphocytes of the fetomaternal interface.During pregnancy,the level of IRF4 in the fetomaternal interface showed a dynamic change,reaching the peak （1.92±0.12） on day 5 of gestation,and was significantly lower than those in unpregnant mice dnring the rest time points of gestation.The levels of IRF4 at 8.5,12.5 and 16.5 days of gestation were 0.25±0.03,0.03± 0.01 and 0.10±0.005,respectively,compared with 1.00±0.04 in unpregant mice （P〈0.05）,and were positively correlated with the level of RORγt （r2=0.6968,P〈0.05）.The mRNA and protein levels of IRF4 in spontaneous abortion group were significantly higher than those in normal pregnancy control group [（1.41 ± 0.04） vs （1.00 ± 0.12）,P〈0.05].The mRNA levels of RORγt and IL-17 in spontaneous abortion group were also higher [RORγt：（2.01 ± 0.03） vs （1.00 ± 0.14）;IL-17：（2.69 ± 0.20） vs （1.00 ± 0.09） （P〈0.05）].Conclusion IRF4 may be playing an important role in the differentiation and functioning of Th17 cells through RORγt,and may participate in maternal immune regulation and affect the outcome of pregnancy.