探讨以抑制致敏小鼠哮喘气道炎症为主的治疗新途径

A new method for inhibition of the inflammation of asthmatic airway in a model of mouse

目的以Ｔｈ１反应拮抗Ｔｈ２反应，抑制哮喘气道以淋巴细胞和嗜酸细胞浸润为主的炎症，探索治疗哮喘的新途径。方法Ｃ５７Ｂ１／６小鼠６０只，腹腔注射０５μｇＰＰＤ２次，间隔２周，第１７、２４天腹腔注射卵清蛋白２次。将小鼠随机分成４组，每组１５只。Ａ组小鼠吸入卵清蛋白；Ｂ组小鼠雾化吸入ＰＰＤ后，雾化吸入卵清蛋白；Ｃ组小鼠吸入卵清蛋白后，雾化吸入ＰＰＤ；Ｄ组小鼠吸入ＰＰＤ，作为对照组。用免疫组化原位杂交检测法检测白细胞介素（ＩＬ）４、ＩＬ５的表达及嗜酸细胞的浸润。结果致敏小鼠单纯雾化吸入卵清蛋白，肺组织出现以ＣＤ＋４Ｔ淋巴细胞和嗜酸细胞为主的炎性浸润，ＣＤ＋４Ｔ淋巴细胞ＩＬ４、ＩＬ５的表达率分别为８７．５％～８９７％与８９０％～８９２％，ＣＤ＋８Ｔ淋巴细胞偶有ＩＬ４、ＩＬ５的表达（＜２％），ＩＬ４ｍＲＮＡ＋、ＩＬ５ｍＲＮＡ＋细胞ＣＤ＋４比例分别为８８７％～９１２％与８９７％～９０６％。雾化吸入ＰＰＤ，特别是激发前３小时雾化吸入ＰＰＤ，显著抑制ＩＬ４、ＩＬ５的表达及嗜酸细胞的浸润。Ｂ组ＩＬ４ｍＲＮＡ＋、ＩＬ５ｍＲＮＡ＋细胞ＣＤ＋４比例及ＣＤ＋４Ｔ淋巴细胞ＩＬ４、ＩＬ５表达率均?

Objective To identify the attenuation of pulmonary Th2 reaction and eosinophil infiltration in ovalbumin sensitized mice with purified protein derivatine (PPD) sensitization and search for the possibility of its clinical use in the management of asthma. Methods 60 C57B1/6 mice were sensitized with PPD and then with ovalbumin and randomized into 4 groups: A, B, C and D group (control group). The A, B and C groups were first challenged with ovalbumin inhalation aerosol PPD was then administered 3 hours before and after obalbumin challenge in the latter two groups respectively. Mice lung was fixed in paraformaldehyde and the expression of IL4 and IL5 was detected with immunocytochemistry in situ hybridization. Results Ovalbumin aerosol inhalation caused a mixed inflammatory infiltration dominated by CD+4T lymphocytes and eosinophils in the lung of sensitized mice. 87.5%～89.7% and 89.0%～89.2% of the CD+4T lymphocytes were positive with IL4 mRNA and IL5 mRNA respectively, while few CD+8T lymphocytes were IL4 or IL5 positive, being less than 2%, 88.7%～91.2% of IL4 mRNA+ cells and 89.7%～90.6% of IL5mRNA+ cells were CD+4T lymphocytes. Aerosol administration of PPD markedly supressed IL4 and IL5 expression and eosinophil infiltration in the lung was attenuated. The attenuation was more effective in the group which received PPD 3 hours before ovalbamin challenge. In the B group CD+4 percentage of IL4mRNA+ and IL5mRNA+ cells and the perentage of the CD+4 with IL4mRNA+ or IL5mRNA+ were markedly lower than those in the A group. In the C group CD+4 perecntage of IL4mRNA+ and IL5mRNA+ cells was also markedly lower than that in the A group, but the percentage of IL4 and IL5 expression of CD+4 cells had no significance as compared with that of the A group, except for the 6hour subgroup. Conclusion It is concluded that sensitization with PPD intraperitoneal injection and then challenge with PPD inhalation markedly attenuated pulmaonary Th2 reaction in ovalbumin sensitized mice, especially if aerosol PPD was administered 3 hours before ovalbamin challenge. 