特异性免疫治疗对哮喘小鼠的作用及机制的初步研究

目的　探讨特异性免疫治疗对哮喘小鼠的作用及其可能机制。方法　通过卵蛋白 (OVA)皮下注射的方法对致敏小鼠进行特异性免疫治疗 ,观察肺组织病理、支气管肺泡灌洗液 (BALF)细胞计数及分类、ELISA检测血清OVA特异性IgE(sIgE)及脾脏T淋巴细胞IL 2和IL 4的分泌 ,3H TdR掺入法检测T淋巴细胞的增殖反应 ,并与OVA致敏及激发的哮喘小鼠相比较。结果　哮喘特异性免疫治疗明显抑制小鼠肺组织炎症病理改变 ;BALF中细胞总数及嗜酸性粒细胞 (EOS)数显著减少 (P <0 .0 5 ) ;血清sIgE显著降低 (P <0 .0 5 ) ;T淋巴细胞IL 2和IL 4的分泌显著降低 (P <0 .0 5 ) ;T淋巴细胞对OVA的特异性刺激的反应显著降低 (P <0 .0 5 )。结论　特异性免疫治疗可显著抑制哮喘小鼠的炎症反应 ;诱导T淋巴细胞无能可能是特异性免疫治疗减轻哮喘相关炎症反应的机制之一

Study on the mechanisms of specific immunotherapy in a murine OVA-sensitized model

Objective To explore the mechanisms and roles of specific immunotherapy in the treatment of allergic asthma through a murine ovalbumin (OVA) -sensitized animal model. Methods The murine model of specific immunotherapy for allergic asthma was established with OVA sensitization, OVA immunotherapy, and OVA challenge. The histological analysis of lung tissues as well as the cell counting and classification of bronchoalveolar lavage fluid (BALF) were performed. The serum level of OVA-specific IgE and production of IL-2 and IL-4 in the spleen-derived T cells were detected by ELISA. The response of T cells to OVA was assayed using 3H-TdR. Results Specific immunotherapy obviously inhibited asthma-associated lung inflammation. The numbers of total cells and eosinophils in BALF from OVA immunotherapy-treated mice were significantly decreased compared with those of non-treated mice (P < 0.05). The serum level of OVA-specific IgE in OVA immunotherapy-treated mice was reduced significantly compared with that of non-treated mice (P < 0.05). The specific immunotherapy was significantly reduced the production of IL-2 and IL-4 in spleen-derived T cells and the specific proliferative response to OVA was decreased remarkably compared with non-treated mice (P < 0.05). Conclusion The present results suggest that specific immunotherapy could inhibit the lung inflammation of allergic asthma mice. The induction of T cells anergy may be one of the mechanisms by which specific immunotherapy alleviate the inflammation of asthma.