Lapa-e-Silva J R, Pretolani M, Bachelet C M, Baker D, Scheper R J, Vargaftig B B
Serviço de Pneumologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Brasil.
Braz J Med Biol Res. 1994 Jul;27(7):1653-8.
Bronchi from guinea pigs actively sensitized to ovalbumin and boosted two weeks later display increased numbers of CD4+ T-lymphocytes and eosinophils. We have further investigated immunopathological changes in sensitized guinea pigs 2 or 24 h after antigenic challenge with ovalbumin. Lungs were resected, frozen and cryostat sections stained with monoclonal antibodies that recognize relevant guinea pig epitopes. Cyanide-resistant peroxidase activity was used to stain eosinophils. No further increase in T-lymphocytes or eosinophils was observed 2 h after challenge. At 24 h, a marked increase in EPO+ eosinophils was found, and this was accompanied by severe mucosal damage characterized by epithelial shedding and ulceration. The numbers of T-lymphocytes remained stable but a novel population of cells with the appearance of dendritic cells was seen in the bronchial wall. They were negative for macrophage markers but were strongly Class II positive. These findings suggest that antigenic challenge results in further recruitment of eosinophils, their activation and release of toxic substances to the epithelium. Furthermore, other cell types, possibly dendritic cells, are attracted to the bronchi and could play a role in maintaining allergic inflammation via antigen presentation.
对卵清蛋白主动致敏并在两周后进行激发的豚鼠支气管，显示出CD4 + T淋巴细胞和嗜酸性粒细胞数量增加。我们进一步研究了用卵清蛋白进行抗原激发后2小时或24小时致敏豚鼠的免疫病理变化。切除肺脏，冷冻后用识别相关豚鼠表位的单克隆抗体对冰冻切片进行染色。用抗氰过氧化物酶活性对嗜酸性粒细胞进行染色。激发后2小时未观察到T淋巴细胞或嗜酸性粒细胞进一步增加。在24小时时，发现EPO +嗜酸性粒细胞显著增加，同时伴有以上皮脱落和溃疡为特征的严重粘膜损伤。T淋巴细胞数量保持稳定，但在支气管壁中可见一群外观呈树突状细胞的新细胞群体。它们对巨噬细胞标志物呈阴性，但强烈呈II类阳性。这些发现表明，抗原激发导致嗜酸性粒细胞进一步募集、其激活并向上皮释放有毒物质。此外，其他细胞类型，可能是树突状细胞，被吸引到支气管，并可能通过抗原呈递在维持过敏性炎症中发挥作用。
