侵袭性肺曲霉菌病鼠模型的建立及γ-干扰素和肺组织细菌负荷的动态变化  

Change of the concentration of IFN-γ and infectious Aspergillus organisms in lung in the model of invasive pulmonary aspergillosis

作　　者：邵长周[1] 瞿介明[1] 何礼贤[1] 张艳红 王晋慧 

机构地区：[1]复旦大学附属中山医院呼吸科,上海200032 [2]中国上海生命科学院生物细胞所,上海200031

出　　处：《中国实用内科杂志》2007年第21期1725-1728,共4页Chinese Journal of Practical Internal Medicine

基　　金：复旦大学青年基金(2005-2007)

摘　　要：目的建立侵袭性肺曲霉菌病模型,探讨不同免疫状态对小鼠抵抗曲霉菌感染能力的影响。方法2006年1月至12月于中国上海生命科学院生物细胞所通过腹腔内注射环磷酰胺后鼻腔内滴入烟曲霉菌(Af)孢子制备侵袭性肺曲霉菌病小鼠模型;获取小鼠肺组织并进行匀浆,接种培养后进行菌落计数,酶联免疫吸附试验(ELISA)法检测γ-干扰素(IFN-γ)质量浓度,部分肺组织进行苏木精-伊红(HE)和六胺银(GMS)染色;以反转录-聚合酶链反应(RT-PCR)检测小鼠肺脏IFN-γ的mRNA表达,观察小鼠死亡率。结果免疫抑制小鼠接种烟曲霉菌后萎靡少动,呼吸急促,口周围出血严重,很少进食水,多随时间延长而表现恶化,肺部真菌负荷呈明显增加趋势,支气管肺泡灌洗液(BALF)中IFN-γ质量浓度随时间推移逐渐升高,48h后保持于较高水平[(932.6±208.36)ng/L],约50%小鼠3d内死亡。病理显示对照组小鼠于接种烟曲霉菌后,支气管旁有大量多型核白细胞(PMN)聚集,炎症呈灶性分布,肺泡壁增厚。免疫受损(ICH)组接种烟曲霉菌后,炎症弥漫分布,肺泡及间质水肿出血剧烈,烟曲霉菌孢子、菌丝呈灶状分布,至48h出现支气管壁破坏、支气管周围坏死、大量炎症细胞浸润,烟曲霉菌菌丝集落成簇出现。结论肺部细胞因子IFN-γ质量浓度与曲霉菌负荷呈一定相关性,机体的免疫功能、T细胞介导的免疫在拮抗曲霉菌感染中发挥着重要作用。Objective To establish the model of invasive pulmonary aspergillosis （IPA） and assay the influence on the host defense against Aspergillus infection when immunity was suppressed in mice. Methods Immunocompromised mice were made by treatment with cyelophosphamide administered intraperitoneally （ i. p. ）. Suspension of conidia was applied to the nostrils of mice to make the model of IPA. Lungs were harvested and homogenized. Portions of homogenates were cultured to determine the number of CFU. IFN-γ in bronchoalveolar lavage fluid was determined by a cytokine-specific ELISA kit. Reverse transcription PCR （RT-PCR） analysis was done to determine the mRNA of IFN-γ in lung cells. Mortality of different rice was calculated. Results Compared with immunocompetent mice, the immunocompromised mice demonstrated a high mortality and had significantly higher concentration of infectious Aspergillus organisms in their lung tissues. In accordance with the increase of Aspergillus organisms ,the levels of IFN-γ in lung tissues got higher. Lung sections from immunocompromised mice revealed patterns of lesions characterized by signs of bronchial wall damage, peribronchial necrosis,and the presence of numerous infiltrating inflammatory cells. Conidia and hyphae were seen in these mice. In contrast,these features were not observed in immunocompetent mice whose lungs were characterized by few in-flammatory cells infiltration,and few fungal growth after inoculation. Conclusion The levels of IFN-γ in lung tissues are related to the infectious Aspergillus organisms. The immunity and T cells play a major role in host defense against Asper-gillus infection.

关 键 词：曲霉菌病 T细胞免疫 死亡率 病理 

分 类 号：R5[医药卫生—内科学]