Green M Gia, Petroff Natasha, La Perle Krista M D, Niewiesk Stefan
Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio.
Department of Veterinary Biosciences, Comparative Pathology and Mouse Phenotyping Shared Resource, Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio.
Comp Med. 2018 Feb 1;68(1):31-40.
Eosinophils have been postulated to play a protective role against infection with respiratory syncytial virus (RSV), increase the severity of allergic asthma during respiratory viral infection, and drive vaccine-enhanced disease. To address these questions in the cotton rat model of RSV infection, we characterized cotton rat eosinophils by electron microscopy as well as by bronchoalveolar lavage and histology of lung sections. Using these methods, we demonstrated that eosinophils comprise approximately half of all cells in the bronchoalveolar lavage fluids from cotton rats. The function of these cells was comparable to that of eosinophils of other species. Ex vivo, eosinophils stimulated with calcium ionophores secreted eosinophil peroxidase. In vivo, treatment with house dust mite antigen increased eosinophil numbers in lung. Infection with Staphylococcus aureus lead to a marked increase in neutrophils without an increase in eosinophils, and eosinophil numbers were not influenced by infection with influenza virus or measles virus. Similarly, infection with RSV did not result in an increase in eosinophils. Lastly, RSV infection did not increase eosinophil recruitment into the lung after challenge with house dust mite antigen, but it did increase eosinophil recruitment into the lungs of cotton rats previously immunized with formalin-inactivated RSV vaccine, thus contributing to vaccine-enhanced disease.
嗜酸性粒细胞被认为在抵抗呼吸道合胞病毒（RSV）感染中发挥保护作用，在呼吸道病毒感染期间会加重过敏性哮喘的严重程度，并引发疫苗增强性疾病。为了在RSV感染的棉鼠模型中解决这些问题，我们通过电子显微镜以及支气管肺泡灌洗和肺组织切片的组织学方法对棉鼠嗜酸性粒细胞进行了表征。使用这些方法，我们证明嗜酸性粒细胞约占棉鼠支气管肺泡灌洗液中所有细胞的一半。这些细胞的功能与其他物种的嗜酸性粒细胞相当。在体外，用钙离子载体刺激的嗜酸性粒细胞会分泌嗜酸性粒细胞过氧化物酶。在体内，用屋尘螨抗原治疗会增加肺中嗜酸性粒细胞的数量。感染金黄色葡萄球菌会导致中性粒细胞显著增加，而嗜酸性粒细胞数量没有增加，并且嗜酸性粒细胞数量不受流感病毒或麻疹病毒感染的影响。同样，RSV感染也不会导致嗜酸性粒细胞增加。最后，RSV感染在屋尘螨抗原激发后不会增加嗜酸性粒细胞向肺内的募集，但会增加先前用福尔马林灭活的RSV疫苗免疫的棉鼠肺内嗜酸性粒细胞的募集，从而导致疫苗增强性疾病。
