支气管哮喘合并肺炎支原体感染小鼠模型白介素9、白介素17、γ干扰素的变化

Changes of interleukin-9, interleukin-17 and interferon γ in bronchoalveolar lavage fluid and peripheral blood in asthmatic mice with mycoplasma pneumonia infection

目的：通过检测支气管哮喘合并肺炎支原体（MP）感染小鼠模型外周血及支气管肺泡灌洗液（BLAF）细胞因子的变化,分析MP感染后是否通过影响哮喘发病相关细胞因子而发挥作用。方法：6~8周的清洁级雌性BALB/c小鼠24只,随机分成哮喘MP感染组（8只）、哮喘非MP感染组（8只）、正常对照组（8只）,并建立相应的小鼠动物模型。运用双抗体夹心酶联免疫吸附试验（ELISA）法对各组BLAF和外周血白介素（IL）-9、IL-17、γ干扰素（IFN-γ）等细胞因子进行检测并对比组间差异。结果：BLAF中IL-9水平在哮喘MP感染模型组高于非MP感染组及正常对照组,差异有统计学意义（P〈0.01）,哮喘非MP感染组也高于正常对照组（P〈0.01）;IFN-γ水平在哮喘MP感染模型组低于非MP感染组及正常对照组,哮喘非MP感染组也低于正常对照组,且均有统计学差异（均P〈0.01）;IL-17水平各组间无显著差异。在各组小鼠外周血中IL-9、IL-17、IFN-γ水平变化亦符合上述改变。结论：哮喘MP感染小鼠BLAF和外周血IL-9水平明显升高,IFN-γ水平则明显下降,IL-17水平无明显变化。

Objective To study the changes of interleukin（IL）-9,IL-17 and interferon-γ（IFN-γ） in mice model of asthma with mycoplasma pneumonia（MP） infection, and analyze the effect of MP infection on these cytokines. Methods Twenty-four clean grade female Balb/c mice aged 6-8 weeks were divided into 3 groups： asthma model infected with MP, asthma model without MP infection and normal controls（8 for each group）. Levels of IL-9, IL-17 and IFN-γ in bronchoalveolar lavage fluid（BLAF） and peripheral blood were detected by enzyme linked immunosorbent assay（ELISA）. Results Level of IL-9 in BLAF increased in the MP infected asthmatic mice model as compared with the group without MP infection and the controls, and level of IL-9 in BLAF of asthmatic mice without MP infection was higher than that of the controls, and the difference were both statistically significant（P〈0.01）. Level of IFN-γ in BLAF decreased in the MP infected asthmatic model as compared with the mice without MP infection and the controls, and level of IFN-γ in BLAF of the asthmatic model without MP infection was lower than that of controls, both were statistically significant（P〈0.01）. There was no statistical difference among the groups in level of IL-17 in BLAF. And the variation of the level of IL-9, IL-7, IFN-γ in mice model peripheral blood all conformed to the changes mentioned above. Conclusions Levels of IL-9 in BLAF and peripheral blood in asthmatic mice with MP infection increased significantly while IFN-γ decreased sharply,and there was no significant change in level of IL-17. These finding indicated the role of IL-9 in asthma with MP infection and deviation of Th1/Th9 might exist after MP infection.