IFN-γ体外诱导沙眼衣原体持续性感染细胞模型的建立

Establishment of the Cell Model for Persistent Infection of Chlamydia Trachomatis Introduced by IFN-γ in vitro

目的:建立γ-干扰素(IFN-γ)体外诱导沙眼衣原体持续性感染的细胞模型。方法:衣原体感染Mc Coy细胞,实验组加入0.5 ng/m L IFN-γ诱导沙眼衣原体,对照组无IFN-γ诱导,空白组为正常培养的Mc Coy细胞,培养72 h后通过光学显微镜、荧光显微镜、电子显微镜分别观察诱导后衣原体的细胞形态。实验组72 h解除IFN-γ诱导,继续培养48 h,观察衣原体细胞形态学变化。结果:实验组在0.5 ng/m L IFN-γ作用72 h后,碘液染色发现衣原体包涵体的数量比对照组减少,包涵体变小;荧光抗体染色显示衣原体包涵体质地疏松,染色不均匀;透射电子显微镜可见包涵体变小和网状体体积增大等特征的典型异形包涵体。去除IFN-γ作用后,包涵体内致密的EB颗粒数量增加。对照组培养72 h后碘液染色和荧光染色可见典型包涵体,透射电子显微镜可见典型的网状体和原体,充满整个包涵体。结论:成功建立了IFN-γ体外沙眼衣原体持续性感染的细胞模型,为进一步进行沙眼衣原体持续性感染形成机制的研究奠定了基础。

Objective： To establish a cell model of interforn- γ mediated persistent Chlamydia trachomatis infection in vitro. Methods： Mc Coy cells were prepared in culture plates and Chlamydia trachomatis serovar D were incubated for infection. Infected cells with treated or untreated IFN-γ at 0. 5 ng / mL for 72 hours and were harvested. Light microscope,fluorescence microscope and electron microscope were used for structural analysis. The culture medium was then removed and replaced with RPMI1640 for 48 hours after the removal of IFN-γ. The morphological characteristics of the Chlamydia were observed. Results： For iodine stained assay,the infected cells mediated by IFN-γ contained small numbers of inclusions by light microscope. Inclusions lacked of density and the fluorescent dye in the IFN-γ mediated inclusions were uneven through direct immunofluorescent staining. Typical RB and EB formed in inclusions of untreated cells were observed by electronic microscope. The IFN-γ treated cells did not contain typical forms,but instead the inclusions were characterized by large atypical reticulate body. Conclusion： An in vitro cell culture system for IFN-γ mediated persistent Chlamydia trachomatis infection have been established. The persistent infection cell model was the foundation for the mechanism research of persistent Chlamydia.