重组粉尘螨Ⅱ类变应原致敏小鼠肺部变应性炎症模型的建立

目的探讨以重组粉尘螨Ⅱ类变应原(rDerf2)建立小鼠肺部变应性炎症模型的方法。方法将30只6～8周龄雌性SPF级BALB/c小鼠,随机分为PBS组(阴性对照组)、卵清蛋白(OVA)组(阳性对照组)和rDerf2组(实验组)。实验组分别于第0、7、14天用rDerf2对小鼠腹腔进行注射致敏;再于第21天开始,连续7d进行雾化激发;对照组分别用PBS和OVA代替。最后一次雾化激发后24h内处死动物,观察肺组织病理变化、支气管肺泡灌洗液(BLAF)中的白细胞计数及分类,用ELISA测定BLAF和脾细胞培养上清中白细胞介素2(IL-2)、IL-4、IL-17和IFN-γ的含量及血清中IgG1、IgE抗体水平变化。结果实验组和阳性对照组BALB/c小鼠肺组织呈现明显的炎症性病理改变;rDerf2组的BALF中白细胞总数〔(17.39±1.03)×106/L〕及嗜酸性粒细胞(EOS)〔(1.61±0.03)×106/L〕计数,均明显高于PBS组(P<0.01);BALF中IL-4〔(78.92±9.06)pg/ml〕、IL-17〔(201.63±31.26)pg/ml〕与PBS组比较呈明显的高水平表达(P<0.01);而IL-2〔(8.29±1.27)pg/ml〕和IFN-γ〔(51.04±15.85)pg/ml〕的含量则显著下降(P<0.01);上述指标在脾细胞培养上清中出现类似的变化。rDerf2组血清中IgE〔(37.63±6.57)IU/ml〕、IgG1〔(16.68±2.90)μg/ml〕的含量表现为Th2型反应增强趋势;但OVA组和rDerf2组间所有指标差异均无统计学意义(P>0.05)。结论用rDerf2腹腔注射致敏后再雾化激发的方式能够成功构建小鼠肺部变应性炎症模型。

The model of pulmonary allergic inflammation in mice established with recombinant group 2 allergen of Dermatophagoides farinae

Objective To establish a model of pulmonary allergic inflammation with BALB/c mice.Methods BALB/c mice were divided into PBS group, OVA group and recombinant Der f 2 protein (rDer f 2) group. The mice in the test group were sensitized by intraperitoneal injection of rDer f 2 at day 0, 7 and 14, and exposed to aerosolized allergen for 7 consecutive days starting from the 21 days. PBS or OVA instead of rDer f 2 was used in the control groups. All mice were executed within 24 h after the final exposure to aerosolized allergen. Pathological changes of the lung, cell counts and classification were studied with IL-2,IL-4, IL-17 and IFN-γ levels in BALF detected by ELISA. Cells from spleen were cultured for 72 h,with IL-2, IL-4, IL-17 and IFN-γ in supernatant, and allergen specific IgG1 and IgE in serum detected by ELISA.Results In the OVA and rDer f 2 groups, the total number of white blood cells [(17.39±1.03)×106/L] and eosinophils [(1.61±0.03)×106/L] in BALF were significantly higher in OVA and rDer f 2 groups than those in PBS group (P<0.01). The levels of IL-4 [(78.92±9.06) pg/ml] and IL-17 [(201.63±31.26) pg/ml] in BALF from OVA and rDer f 2 groups were significantly increased (P<0.01), compared with those in PBS group. On the contrary, levels of IL-2 [(8.29±1.27) pg/ml] and IFN-γ [(51.04±15.85) pg/ml] in BALF were reduced significantly (P<0.01). The similar trends were also detected in terms of the above cytokines in the supernatants of spleen cell cultures. Moreover, the levels of IgE [(37.63±6.57) IU/ml], IgG1 [(16.68±2.90) μg/ml] in OVA and rDer f 2 groups were also significantly increased in serum than those in PBS group (P<0.01). The phenomenon indicated that Th2-type immune response was enhanced and Th1-type immune response was reduced, with no statistically significant difference between OVA and rDer f 2 groups (P>0.05) observed.Conclusion A pulmonary allergic inflammation model of BALB/c mice can be established successfully by intraperitoneal injection followed by aerosolization with rDer f 2 protein.