Narita M, Yamada M, Tsuboi T, Kawashima K
National Institute of Animal Health, Shichinohe, Kamikita, Aomori 039-2586, Japan.
Vet Pathol. 2003 Mar;40(2):128-35. doi: 10.1354/vp.40-2-128.
The effects of immunosuppression were examined in 1.5-month-old calves that were given dexamethasone (DM) before endobronchial inoculation with bovine adenovirus type 3 (BAV-3). Immunohistopathologically, severe necrotizing bronchiolitis with eosinophilic and basophilic intranuclear inclusion bodies was observed both in DM-treated 1.5-month-old infected calves and in non-DM-treated 7-day-old infected calves. These inclusion bodies were correlated with the detection of BAV-3 antigen and viral particles. The presence of inclusion bodies in the desquamated epithelial cells or of BAV-3 antigen, or both, correlated well with the isolated level of BAV-3 in bronchoalveolar lavage (BAL) fluid. Few immunoglobulin (IgG, IgM, and IgA)-containing B lymphocytes or CD8+ T lymphocytes infiltrated the pneumonic lesion in both the 7-day-old and the DM-treated 1.5-month-old infected calves. Thus, depletion of CD8+ T lymphocytes in calves might influence the clearance of BAV-3 from respiratory tissues.
在1.5月龄的犊牛中研究免疫抑制的作用，这些犊牛在经支气管接种3型牛腺病毒（BAV-3）之前给予地塞米松（DM）。免疫组织病理学检查发现，在经DM处理的1.5月龄感染犊牛和未经DM处理的7日龄感染犊牛中均观察到严重的坏死性细支气管炎，并伴有嗜酸性和嗜碱性核内包涵体。这些包涵体与BAV-3抗原和病毒颗粒的检测相关。脱落的上皮细胞中包涵体的存在或BAV-3抗原的存在，或两者兼而有之，与支气管肺泡灌洗（BAL）液中BAV-3的分离水平密切相关。在7日龄和经DM处理的1.5月龄感染犊牛中，很少有含免疫球蛋白（IgG、IgM和IgA）的B淋巴细胞或CD8+T淋巴细胞浸润到肺部病变中。因此，犊牛中CD8+T淋巴细胞的耗竭可能会影响BAV-3从呼吸组织中的清除。
