约氏疟原虫子孢子感染对大鼠腹腔巨噬细胞B7.1、B7.2分子表达的影响

Expressions of B7.1 and B7.2 in macrophagus of rats infected by Plasmodium yoelii

目的研究约氏疟原虫感染后协同刺激分子B7.1、B7.2在大鼠腹腔巨噬细胞的表达情况,探讨B7.1、B7.2分子在宿主抵抗疟原虫感染免疫中的作用。方法利用约氏疟原虫感染大鼠的动物模型,分别在感染约氏疟原虫子孢子后2、12、24、48、72h分离获得大鼠腹腔巨噬细胞,通过免疫荧光及激光扫描共聚焦显微镜技术定量分析B7.1、B7.2分子表达情况。结果在宿主感染约氏疟原虫后巨噬细胞B7.1、B7.2分子表达增加;B7.1上调较缓慢,并在72h后出现回落;B7.2上调非常迅速,在48h达到峰值,从72h开始略有下降;在所选时间范围内B7.2的表达水平始终高于B7.1(P<0.05)。结论疟原虫子孢子感染大鼠后,B7.1、B7.2分子表达水平发生改变,提示协同刺激因子参与了宿主免疫系统活化,推测该现象与受疟原虫感染哺乳动物机体的免疫防御、免疫调控密切相关。

Objective To study the expression levels of B7.1 and B7.2 in the macrophagus of rats infected with the Plasmodium yoelii sporozoites and investigate the roles of these costimulators in parasite infection immunity. Methods The mammal model was established by infecting rats with the sporozoites, then macrophagus was separated from the rat abdominal cavity 2, 12, 24, 48, 72 h after infection. The expressions were quantitative analyzed by immunofluorescence staining and laser scanning confocal microscopy. Result The expressions of B7.1 and B7.2 were upregulated after infected with the sporozoites. The expression of B7.1 was slowly induced and then descended at 72 h. B7.2 was rapidly induced and maximally expressed at 48 h and downregulation at 72 h. The expression of B7.2 was significantly higher than that of B7.1 at all time points assayed after stimulation （P 〈 0.05）. Conclusion The changes of B7.1 and B7.2 expressions on macrophagus manifest these costimulators are involved in activating the mammal host immune defense and immunoregulation after Plasmodium yoelii sporozoites invaded.