Liang S C, Simecka J W, Lindsey J R, Cassell G H, Davis J K
National Animal Center, National Defense Medical Center, Taipei, Taiwan, ROC.
Lab Anim Sci. 1999 Aug;49(4):385-94.
Sendai virus infection in rats is an excellent model for studying development and role of host defenses throughout the respiratory tract after this infection. Therefore, development of serum antibody responses and disease were studied.
Forty-two anesthetized pathogen-free 3- to 4- week-old LEW/NCr rats were inoculated intranasally with Sendai virus. At postinoculation days 0, 2, 3, 5, 8, 10, and 14, rats were euthanized by administration of a pentobarbital sodium overdose followed by exsanguination. Serum was obtained from all animals, and nasal wash and bronchoalveolar lavage specimens were collected during selected experiments. An ELISPOT assay was used to measure numbers of Sendai virus-specific antibody-forming cells in respiratory tract lymphoid tissue.
Recovery from disease and clearance of virus from respiratory tract tissues coincided with development of serum antibody responses. Upper respiratory tract lymph nodes were the initial and major sites of appearance of antibody-forming cells. Immunoglobulin G was the predominant subtype of these cells during recovery from the infection and in rats resistant to infection. Passive transfer of antisera or specific IgG protected the lower but not the upper respiratory tract.
Circulating components of immunity have a major role in resistance and recovery from disease in the lower respiratory tract, whereas local responses are likely involved in protection of the upper respiratory tract. Local lymphoid tissues are the major production sites of IgG, which contributes to resistance to and recovery from respiratory tract diseases.
大鼠仙台病毒感染是研究该感染后整个呼吸道宿主防御的发育及作用的理想模型。因此，对血清抗体反应的发育及疾病情况进行了研究。
将42只3至4周龄、麻醉状态下的无特定病原体LEW/NCr大鼠经鼻接种仙台病毒。在接种后的第0、2、3、5、8、10和14天，通过过量给予戊巴比妥钠使大鼠安乐死，随后放血。从所有动物获取血清，并在选定实验中收集鼻腔冲洗液和支气管肺泡灌洗标本。采用酶联免疫斑点分析（ELISPOT）来测定呼吸道淋巴组织中仙台病毒特异性抗体形成细胞的数量。
疾病的恢复以及呼吸道组织中病毒的清除与血清抗体反应的发育同步。上呼吸道淋巴结是抗体形成细胞最初出现且主要存在的部位。在感染恢复过程中以及对感染有抵抗力的大鼠中，免疫球蛋白G是这些细胞的主要亚型。抗血清或特异性IgG的被动转移可保护下呼吸道，但不能保护上呼吸道。
免疫的循环成分在抵抗下呼吸道疾病及从中恢复过程中起主要作用，而局部反应可能参与上呼吸道的保护。局部淋巴组织是IgG的主要产生部位，其有助于抵抗呼吸道疾病并从中恢复。
