嗜肺军团菌感染不同时间血清IL-12浓度的变化

目的探讨嗜肺军团菌感染对机体血清IL-12水平的影响,阐述嗜肺军团菌感染对机体免疫功能的作用。方法将BALB/C小鼠随机分为实验组和对照组,实验组又分为实验1周组、2周组、3周组、4周组;每个实验组分别在该周第3天时间点观察,每个实验组15只小鼠;对照组15只小鼠。实验组在腹腔内注射含有嗜肺军团菌菌液0.2ml,菌液浓度为1×10^6/ml,对照组在腹腔内注射无菌生理盐水0.2ml。分别在感染第1周至第4周内的相应时间点,采集小鼠血清,利用酶联免疫吸附法（ELISA）观察血清IL-12水平在第1～4周的动态变化。结果感染嗜肺军团菌后第1周到第3周两组比较,血清IL-12水平明显下降,有统计学意义（P〈0.05）;而第4周两组比较,无统计学意义（P〉0.05）;嗜肺军团菌感染后前两周血清IL-12水平明显下降,并在第2周内达到最低水平;在第3周血清IL-12水平有上升趋势;在感染第4周后血清IL-12水平基本恢复到正常水平。结论研究结果显示,嗜肺军团菌感染对机体免疫功能在不同的时期可能有不同的作用,既在感染早期表现为机体免疫功能下降,而在感染后期对机体免疫功能影响逐渐减少,机体免疫功能逐渐恢复正常。

The changes of IL-12 in serum in different periods after Legionella pneumophilia infection

Objective To explore what effect of LP infection has on immunity by observing the changes of the levels of IL-12 in serum in different periods after LP infection in BALB/C mice. Methods Two groups were designed, one control group and one infected group. The infected group had four subgroups which had 15 BALB/C mice in each subgroup. Observing point was set in every week （the third day） dur- ing four weeks. 0.2 ml LP liquid （ 1 × 10^6/ml） was injected into BALB/C mouse abdomen cavity in infected group and the same amount of saline was injected into BALB/C mouse abdomen cavity in control group. The changes of IL-12 were determined with standard Sandwich ELISA. Results In infected group, the level of IL-12 in serum was decreased remarkably, the two groups showed significant differences with P 〈0.05. But in the fouth week there was no significant difference between two groups in IL-12 level in serum. The level of IL-12 in serum decreased remarkably and became lower in the first two weeks after LP infection. The level of IL-12 in serum was the lowest in the second week after LP infection. There was an increasing trend in the level of IL-12 in serum in the third week after LP infection. The level of IL-12 in serum became normal in the fourth week after LP infection. Conclusion The study showed that LP infection had different effects on immune function in different periods. In the early period of LP infection the immune function decreased and in the late period of LP infection the immune function recovered to normality gradually.