贝氏柯克斯体新桥株刺激人树突状细胞的表型分析  

Phenotypic analysis of dendritic cells stimulated with the Xinqiao strain of Coxiella burnetti

作　　者：王颖[1] 吴德平[1] 王锡乐[1] 陈梅玲[1] 尉雁[1] 温博海[1] 

机构地区：[1]军事医学科学院微生物流行病研究所,病原微生物生物安全国家重点实验室,北京100071

出　　处：《中国人兽共患病学报》2009年第11期1041-1045,共5页Chinese Journal of Zoonoses

基　　金：国家自然科学基金资助(30670101)

摘　　要：目的树突状细胞(dendritic cell,DC)具有成熟与未成熟两种形态,前者是早期免疫应答强有力的抗原呈递细胞,后者能诱导免疫耐受。分析贝氏柯克斯体(Coxiella burnetii,Cb)、Cb脂多糖(LPS)、去除LPS的Cb对DC的激活作用,探讨Cb逃逸宿主免疫清除的机理。方法从健康成年人的外周血中分离单核细胞,加入GM-CSF和IL-4体外培养单核细胞成未成熟DC;分别用灭活Cb、Cb LPS、去LPS Cb刺激体外培养未成熟DC,大肠杆菌LPS作为阳性对照刺激因子;刺激后24h,用流式细胞仪(fluorescence activated cell sorter,FACS)检测DC表面分子:成熟标记分子CD83与共刺激分子CD40、CD58、CD80、CD86。结果去LPS Cb刺激DC表面分子表达水平与大肠杆菌LPS刺激最相近,显著强于未刺激DC,而灭活Cb、Cb LPS刺激DC表面分子CD83、CD40、CD80、CD86的表达在一低水平。结论LPS遮盖了Cb激活DC所需的表面分子,除去LPS后暴露的分子与DC相互作用,对DC的成熟刺激作用显著高于灭活Cb、Cb LPS的刺激作用。LPS的存在有利于贝氏柯克斯体逃逸宿主的免疫清除。Dendritic cells（DCs） show two morphological forms,the mature and immature forms;the former is the potent antigen-presenting cells（APC） initiating the primary immune responses,while the latter processes different properties from the former and has the ability to induce T cell tolerance Coxiella burnetti（Cb） is an obligate intracellular microorganism and its mechanism by which this bacterium evades the action of immune clearance of host during persistent infection is still unknown.In the present study,mononuclear cells were isolated from human peripheral blood and cultivated in media containing GM-CSF and IL-4 to generate the immature DCs.The immature DCs generated were stimulated with the Xingqiao strain of Cb（an isolate in China and an virulent phase I strain with full-length LPS） and LPS-removed Cbs with LPS of E.coli used as the positive control.Meanwhile,the expressions of surface molecules on the stimulated DCs,such as CD40,CD58,CD80,CD83 and CD86,were analyzed with FACS.It was demonstrated that the expression levels of these surface molecules on DCs pulsed with LPS-removed Cbs were approached to that of E.coli LPS-pulsed DCs and significantly higher than that of the un-stimulated DCs.However,the expression of these surface molecules of Cbs or Cb LPS-pulsed DCs was dramatically lower compared with that of E.coli LPS-pulsed DCs.It is apparent that the virulent phase I C.burnetti with full-length LPS is unable to activate DCs,but the LPS-removed C.burnetti possess this ability.This result suggests that LPS can block the surface molecules of C.burnetti interacting with DCs and these molecules are necessary for the activation ofDCs.The presence of LPS is beneficial for the immune evasion strategy of virulent phase I strain of C.burnetti.

关 键 词：贝氏柯克斯体 树突状细胞 表面分子 流式细胞分析 

分 类 号：R376[医药卫生—病原生物学]