不同品系小鼠哮喘模型的建立与比较

Establishment and comparison of asthma models in different strains of mice

目的:比较不同品系小鼠哮喘模型的差异。方法:将BALB/c和C57BL/6两品系雄鼠随机分为对照组与哮喘组,每组6只。采用卵清蛋白(OVA)和氢氧化铝混悬液致敏和激发小鼠,激发过程中观察小鼠哮喘症状。取支气管肺泡灌洗液(BALF)进行细胞分类计数,酶联免疫吸附试验(ELISA)法检测白介素(IL)-4和干扰素(IFN)-γ浓度,苏木精—伊红(HE)染色及过碘酸雪夫(PAS)染色观察肺组织病理学改变。Western blotting及免疫组织化学染色法检测肺组织中NOD样受体蛋白3(NLRP3)、caspase 1和凋亡相关斑点样蛋白(ASC)蛋白表达。结果:BALB/c小鼠哮喘组出现点头呼吸、腹部痉挛、抓耳挠腮、呼吸减慢等更具特异性的哮喘症状,而C57BL/6小鼠哮喘组仅表现为少动、呼吸深快。与BALB/c对照组及C57BL/6哮喘组比较,BALB/c哮喘组BALF中细胞总数和嗜酸性粒细胞比例、血清IL-4含量及肺组织NLRP3、caspase 1和ASC蛋白表达量升高,血清IFN-γ水平下降(均P<0.01),肺组织可见特征性的病理改变。与C57BL/6对照组比较,C57BL/6哮喘组BALF中炎症细胞总数、嗜酸性粒细胞数及肺组织炎症小体相关蛋白表达量升高(P<0.01),但IL-4与IFN-γ浓度无改变(P>0.05)。结论:BALB/c小鼠哮喘模型较C57BL/6小鼠哮喘模型更为稳定,两者间的差异可能与异常激活的NLRP3炎症小体有关。

Objective:To compare the differences of asthma models in different strains of mice.Methods:Male mice of BALB/c and C57 BL/6 were randomly divided into control group and asthma group(n=6).Mice were sensitized and stimulated by suspension of ovalbumin(OVA) and aluminum hydroxide,and asthma symptoms were observed during the stimulation.Bronchoalveolar lavage fluid(BALF) was taken for cell classification and counting.ELISA was used to detect IL-4 and IFN-γ contents.HE staining and PAS staining were employed to observe the pathological changes of lung tissues.The expressions of NLRP3,caspase1 and ASC proteins in lung tissues were detected by western blotting and immunohistochemical staining.Results:The asthma group of BALB/c mice showed more specific asthma symptoms such as nodding breathing,abdominal cramps,scratching the ears and cheeks,and slow breathing,while C57 BL/6 asthma group only showed less movement and rapid breathing.Compared with BALB/c control group and C57 BL/6 asthma group,the total number of cells,the proportion of eosinophils in BALF,IL-4 level,and the protein expression of NLRP3,caspase 1 and ASC were increased in the BALB/c asthma group,while the serum IFN-γ level was significantly decreased(P<0.01).There were characteristic pathological changes in lung tissues.Compared with the C57 BL/6 control group,the total number of inflammatory cells,the number of eosinophils and the expression of inflammatory body related protein in BALF of C57 BL/6 asthma group were significantly increased(P<0.01),while the concentrations of IL-4 and IFN-γ did not change significantly(P>0.05).Conclusion:The asthma model of BALB/c mice is more stable compared with C57 BL/6 mice model,and the difference between the two strains may be related to the abnormally activated NLRP3 inflammasome.