系统性白念珠菌感染小鼠IL-12和IL-23的表达

目的了解系统性白念珠菌感染小鼠IL-12和IL-23的表达特征,探讨IL-23在抗白念珠菌系统感染中的作用,并重新认识和评价IL-12的作用。方法通过尾静脉接种白念珠菌建立小鼠白念珠菌系统感染模型,观察小鼠肾脏的病理变化,RT-PCR法检测小鼠肾脏IL-23及IL-12mRNA的相对表达水平,平皿稀释法检测肾脏内菌落形成单位(CFU)。结果IL-12mRNA表达水平在初次感染后第1、3天明显升高(P<0.05),感染后第7天基本正常。IL-23mRNA水平在初次感染后的第1天无明显改变(P>0.05),感染后第3、7天明显升高(P<0.05),而再次感染中其mRNA始终呈现高表达(P<0.05)。结论IL-12和IL-23均参与I型免疫反应,有效抵御白念珠菌系统感染,IL-12可能在炎症反应的早期发挥重要作用,而IL-23可能在炎症反应的后期发挥重要作用。

The expression of IL- 12 and IL- 23 in mice with systemic Candida albicans infection

Objective: To measure the expression of IL-23 and IL-12 in mice with disseminated candidiasis, in order to understand the role of IL-23 in the anti-systemic Candida albicans infection. Methods: The model of systemic Candida albicans infection was established by injection of the pathogenic fungi into the tail-vein of mouse to observe the pathological changes in the kidney of the mouse. RT-PCR was applied to detect the expression of IL-23 mRNA and IL-12 mRNA in the kidney. Colony forming unit (CFU) of the infected kidney was determined with the plating dilution methods. Results: The level of IL-12 mRNA was evidently higher than that of the normal controls on day 1 and day 3 (P<0.05), and gradually returned to normal on day 7. In the primary infection the level of IL-23 mRNA started to rise on day 3 and day 7, while the expression of IL-23 mRNA rose to a high level from the beginning and persisted for the whole process. in the secondary infection (P<0.05). Conclusion : Both IL-12 and IL-23 are involved in type-I immune response and resist effectively against systemic Candida albicans infection. It is postulated that IL-12 may play an important role in the early phase of the inflammation, while IL-23 takes effect in the late phase.