Lin X Q, O eilly K L, Storz J, Purdy C W, Loan R W
Department of Veterinary Microbiology and Parasitology, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803, USA.
Arch Virol. 2000;145(11):2335-49. doi: 10.1007/s007050070024.
Antibody responses against respiratory bovine coronavirus (RBCV) infections were monitored in cattle from the onset of a naturally occurring severe shipping fever (SF) epizootic to complete recovery of affected cattle or fatal outcomes. The infection with RBCV was detected in nasal secretions of 86 cattle, and 81 of them developed acute respiratory tract disease, including fatal pneumonia. Cattle nasally shedding RBCV at the beginning of the epizootic experienced characteristic primary immune responses with specific antibodies for hemagglutinin-esterase (HE) and spike (S) glycoproteins. Virus shedding in nasal secretions of the majority of the cattle ceased between days 7 and 14 with the appearance of HE- and S-specific antibodies. Nasal samples and lung tissues from 9 of the 10 fatal cases had high titers of RBCV, but these cattle had only IgM responses to RBCV infections. Cattle remaining negative in RBCV isolation tests entered this epizootic with antibodies against HE and S. Protection against respiratory tract disease was apparently associated with high level of opsonic and virus-neutralizing IgG2. The HE and S glycoproteins were recognized earliest by the bovine immune system while the N protein induced antibody responses during the later stage of initial infection and the early stage of reinfection. The membrane (M) glycoprotein was the least immunogenic of the major viral structural proteins.
从自然发生的严重运输热（SF） epizootic开始到受影响的牛完全康复或出现致命结果，对牛针对呼吸道牛冠状病毒（RBCV）感染的抗体反应进行了监测。在86头牛的鼻分泌物中检测到RBCV感染，其中81头出现急性呼吸道疾病，包括致命性肺炎。在 epizootic开始时鼻腔排出RBCV的牛经历了针对血凝素酯酶（HE）和刺突（S）糖蛋白的特异性抗体的典型初次免疫反应。随着HE和S特异性抗体的出现，大多数牛的鼻分泌物中的病毒排出在第7天至14天之间停止。10例致命病例中有9例的鼻样本和肺组织中RBCV滴度很高，但这些牛对RBCV感染只有IgM反应。在RBCV分离试验中保持阴性的牛在进入此次 epizootic时带有针对HE和S的抗体。对呼吸道疾病的保护显然与高水平的调理素和病毒中和IgG2有关。牛免疫系统最早识别HE和S糖蛋白，而N蛋白在初次感染后期和再次感染早期诱导抗体反应。膜（M）糖蛋白是主要病毒结构蛋白中免疫原性最低的。
