粉尘螨1类变应原重组融合表位免疫治疗小鼠哮喘的效果分析

Effect of immunotherapy of recombinant chimeric epitopes of major allergen group 1 from Dermatophagoides farina on asthma of mice

目的探讨粉尘螨1类变应原重组融合表位对哮喘小鼠的免疫治疗效果。方法将40只小鼠随机分为阴性对照组、哮喘组、Der f 1治疗组和重组融合变应原Der f 1A治疗组等4组。哮喘组、Der f 1治疗组和Derf 1A治疗组小鼠用粉尘螨提取液于第1、7、14 d进行3次腹腔注射致敏,并于第21 d开始雾化吸入激发,持续7 d。其中治疗组于雾化吸入前30 min,分别用Der f 1、Der f 1A进行特异性免疫治疗。对照组用磷酸盐缓冲液(PBS)进行腹腔注射和雾化吸入。完成雾化吸入激发后,计数支气管肺泡灌洗液(BALF)中白细胞总数;观察肺组织病理切片;检测BALF与脾细胞培养上清液(SCCS)中IL-5、IFN-γ和血清中特异性Ig E、Ig G2a水平。结果与哮喘组相比,免疫治疗组小鼠肺部炎症明显减轻,且BALF中白细胞总数明显降低;免疫治疗组小鼠BALF和SCCS中IL-5水平显著降低,IFN-γ水平则显著升高;血清中变应原的特异性Ig E抗体水平显著降低,Ig G2a抗体水平则显著升高(P均<0.01)。结论粉尘螨1类变应原重组融合表位能够有效减轻小鼠的哮喘症状,为诊断和治疗过敏性哮喘奠定了基础。

Objective To investigate the effect of immunotherapy of recombinant chimeric epitopes of major allergen group 1 from Dermatophagoidesfarina on asthma of mice. Methods Forty mice were randomly divided into 4 groups ： a negative con- trol group, an asthma group, an immunotherapy group of Der f 1, and an immunotherapy group of Der f 1A. On the 1 st, 7th and 14th day, the mice in the asthma group, immunotherapy group of Der f 1, and immunotherapy group of Der f 1A were injected intraperitoneaIly with the extract of D. farina 3 times to sensitize; and on the 21st day, the atomized inhalation was carried out for 7 days. In the control group, phosphate buffer solution （PBS） was applied for sensitization and inhalation. In the immunother- apy groups, Der f 1 and Der f 1A were applied to carry out the specific immunotherapy respectively for 30 min before the inhala- tion. Then, the leukocytes in the bronchoalveolar lavage fluid （BALF） were numbered and the pathological sections of lung tis- sues were observed; IL-5 and IFN-T in BALF and spleen cell culture supematants （SCCS） as well as the specific IgE, IgG2a in the sera were detected. Results Compared with the asthma group, the lung inflammation of mice in the immunotherapy groups was lightened, and the total numbers of leukocytes in BALF were significantly reduced ; IL-5 was significantly reduced and IFN- ~/was significantly increased in BALF and SCCS of mice in the immunotherapy groups ; and the specific IgE was significantly re- duced and IgG2a was significantly increased in the sera of mice in the immunotherapy groups （all P〈 0.01 ）. Conclusion The recombinant chimeric epitopes of major allergen group 1 from D. farina could effectively relieve the symptom of asthma in mice, so as to provide the evidence for specific immunotherapy.