【摘要】 目的·比较问号钩端螺旋体56606v株和56606a株对小鼠巨噬细胞的感染情况,探究致病性钩端螺旋体的致病机制。方法·用问号钩端螺旋体强毒株56606v株和减毒株56606a株分别感染C57BL/6小鼠腹腔巨噬细胞后,对样本进行免疫荧光染色,观察巨噬细胞对钩端螺旋体的吞噬及清除能力,并通过realtime-PCR检测感染后巨噬细胞的细胞因子的表达。结果·免疫荧光染色和realtime-PCR结果均发现在感染72 h后,56606v株仍能在巨噬细胞中存活,而56606a株不能在巨噬细胞中存活;巨噬细胞对56606v株的吞噬率高于对56606a株的吞噬率,而感染56606v株后细胞因子的表达低于感染56606a株后的水平。结论·问号钩端螺旋体强毒株56606v株能在巨噬细胞中存活,并引起较低的炎症反应,可借此逃避免疫细胞的杀伤从而引发疾病;而减毒株56606a株被巨噬细胞吞噬后则被清除,且引发较强的炎症反应,易被机体免疫细胞清除,从而不引起疾病。更多还原

【Abstract】 Objective · To compare the response and consequence of mouse macrophages infected by Leptospira interrogans 56606 v and 56606 a, and explore the mechanisms of pathogenic Leptospira to cause disease. Methods · Peritoneal macrophages of C57 BL/6 mice were infected by pathogenic Leptospira 56606 v and non-pathogenic Leptospira 56606 a respectively. Immunofluorescence staining was performed to observe phagocytosis and clearance of Leptospira after infection, and realtime-PCR was used to determine cytokine production of macrophages. Results · After 72-hour infection,strain 56606 v exhibited a lower phagocytic rate but survived after incubation with peritoneal macrophages compared with strain 56606 a, which showed a higher phagocytic rate but was cleared at that time point. Additionally, cytokine production of macrophages incubated with 56606 v was lower than that with 56606 a. Conclusion · Leptospira interrogans strain 56606 v can survive in macrophages, which may contribute to evasion from phagocytic clearance and lead to disease, while strain 56606 a can be cleared, which implicates a lower pathogenicity.更多还原