Russo M, Jancar S, Pereira de Siqueira A L, Mengel J, Gomes E, Ficker S M, Caetano de Faria A M
Departmento de Imunologia, Instituto de Ciências Biomédicas, ICB-III, Universidade de São Paulo, SP, Brazil.
Immunol Lett. 1998 Mar;61(1):15-23. doi: 10.1016/s0165-2478(97)00155-7.
Airway inflammation plays a major role in human asthma. Increasing evidence points to a close correlation between eosinophil infiltration and allergic lung disease. A new murine model of eosinophilic lung inflammation has recently been developed; it consists of immunizing mice with small fragments of solidified hen egg white implanted (EWI) into the subcutaneous tissue. In this model, which is further characterized here, mice challenged with ovalbumin (OVA) present an intense and persistent lung eosinophilia, as well as histopathological findings that resemble human asthma. In the present work, the effect of oral tolerance on the development of allergic lung inflammation in B6 mice immunized with antigen plus adjuvant or with EWI is investigated. It was found that in mice rendered orally tolerant by previous exposure to antigen in the drinking water, the T-helper type 2 cell (Th2)-associated allergic responses in both protocols of immunization were almost completely abolished. The allergic responses were assessed by pulmonary and bone marrow eosinophilia, lung histopathology and antigen-specific IgE and IgG1 production. These findings provide the first indication that Th2-associated lung pathology can be prevented by oral tolerance.
气道炎症在人类哮喘中起主要作用。越来越多的证据表明嗜酸性粒细胞浸润与过敏性肺病之间存在密切关联。最近建立了一种新的嗜酸性粒细胞性肺炎症小鼠模型；该模型是通过将凝固的鸡蛋白小片段植入（EWI）皮下组织来免疫小鼠。在此进一步描述的该模型中，用卵清蛋白（OVA）攻击的小鼠表现出强烈且持续的肺部嗜酸性粒细胞增多，以及类似于人类哮喘的组织病理学发现。在本研究中，研究了口服耐受对用抗原加佐剂或EWI免疫的B6小鼠过敏性肺炎症发展的影响。结果发现，在通过先前在饮用水中接触抗原而产生口服耐受的小鼠中，两种免疫方案中与2型辅助性T细胞（Th2）相关的过敏反应几乎完全被消除。通过肺部和骨髓嗜酸性粒细胞增多、肺组织病理学以及抗原特异性IgE和IgG1的产生来评估过敏反应。这些发现首次表明口服耐受可以预防与Th2相关的肺部病理。
