泡球蚴感染小鼠肝脏中CXCR5和转录因子BCL-6表达的变化特点研究

Study on characteristics of changes in expression of the Tfh cell-related molecule CXCR5 and transcription factor BCL-6 in the livers of mice infected with Echinococcus multilocularis

目的检测泡球蚴感染小鼠肝组织中的Tfh细胞相关分子CXCR5和转录因子BCL-6表达水平,分析其在泡球蚴感染过程中的动态变化特点及免疫作用机制。方法将60只雌性BALB/c小鼠随机分为实验组和对照组,将BALB/c小鼠开腹,肉眼直视下肝左叶注射0.1ml泡球蚴混悬液,建立小鼠肝泡球蚴感染模型,对照组以相同方法注射等量生理盐水。分别于感染后8、90、200d将小鼠处死,取肝脏,制作病理切片,HE染色后观察病理变化;采用免疫组化法检测肝组织CXCR5和BCL-6动态变化;采用实时荧光定量PCR检测肝组织中CXCR5和BCL-6mRNA的表达。结果与对照组相比,泡球蚴感染中期和晚期小鼠肝脏肝细胞胞浆CXCR5和BCL-6高表达。CXCR5阳性率分别为(8.00±1.35)%和(10.37±1.17)%,BCL-6阳性率分别为(14.50±1.79)%和(24.55±1.29)%,且主要分布于泡球蚴的纤维囊壁及感染灶周围;CXCR5和BCL-6mRNA水平在感染中期升高,并持续高表达至晚期。结论 BALB/c小鼠感染泡球蚴后肝脏细胞高表达Tfh细胞相关分子CXCR5及转录因子BCL-6。在CXCR5和BCL-6作用下,Tfh细胞可能参与泡球蚴感染免疫过程。

Objective To measure changes in the Tfh cell-related molecule CXCR5 and transcription factor BCL-6 in order to discuss the mechanism of immune action of Tfh cells during infection with Echinococcus multilocularis. Methods Sixty female BALB/c mice were randomly divided into an experimental group and a control group.The abdomen of mice in the experimental group was opened and mice were injected with 0.1 ml of an E.multilocularis metacestode suspension in the left lobe of the liver;control mice were injected with 0.1 ml of saline using the same surgical procedure.Ten mice from the infected group and ten mice from control group were sacrificed on day 8,90,and 200 post-infection.HE staining was used for pathological analysis.The expression of CXCR5 and BCL-6 was detected immunohistochemically.Transcripts of CXCR5 and BCL-6 were detected with QRT-PCR. Results Compared to the control group,mice infected with E.multilocularis had increased levels of CXCR5 and BCL-6 expression in liver tissue.CXCR5 was detected at a rate of（8±1.35）%in control mice and（10.37±1.17）%in infected mice.BCL-6 was detected at a rate of（14.50±1.79）%in control mice and（24.55±1.29）%in infected mice.Expression was noted in the fibrous wall and germinal layer of cysts.The level of CXCR5 and BCL-6 mRNA expression increased in the middle stages of infection and remained high in the late stages. Conclusion Tfh cells may be involved in the immune response to echinococcosis via CXCR5 and BCL-6.