Ricklin Meret E, Garcìa-Nicolàs Obdulio, Brechbühl Daniel, Python Sylvie, Zumkehr Beatrice, Posthaus Horst, Oevermann Anna, Summerfield Artur
Institute of Virology and Immunology, Mittelhäusern, Switzerland.
Vetsuisse Faculty, Institute for Animal Pathology, University of Bern, Bern, Switzerland.
Vet Res. 2016 Feb 24;47:34. doi: 10.1186/s13567-016-0319-z.
Pigs are considered to be the main amplifying host for Japanese encephalitis virus (JEV), and their infection can correlate with human cases of disease. Despite their importance in the ecology of the virus as it relates to human cases of encephalitis, the pathogenesis of JEV in pigs remains obscure. In the present study, the localization and kinetics of virus replication were investigated in various tissues after experimental intravenous infection of pigs. The data demonstrate a rapid and broad spreading of the virus to the central nervous system (CNS) and various other organs. A particular tropism of JEV in pigs not only to the CNS but also for secondary lymphoid tissue, in particular the tonsils with the overall highest viral loads, was observed. In this organ, even 11 days post infection, the latest time point of the experiment, no apparent decrease in viral RNA loads and live virus was found despite the presence of a neutralizing antibody response. This was also well beyond the clinical and viremic phase. These results are of significance for the pathogenesis of JEV, and call for further experimental studies focusing on the cellular source and duration of virus replication in pigs.
猪被认为是日本脑炎病毒（JEV）的主要扩增宿主，它们的感染与人类疾病病例相关。尽管猪在与人类脑炎病例相关的病毒生态学中很重要，但JEV在猪体内的发病机制仍不清楚。在本研究中，对猪进行实验性静脉感染后，研究了病毒在各种组织中的定位和复制动力学。数据表明病毒迅速广泛传播至中枢神经系统（CNS）和其他各种器官。观察到JEV在猪体内不仅对中枢神经系统有特殊嗜性，对次级淋巴组织也有特殊嗜性，特别是扁桃体，其病毒载量总体最高。在该器官中，即使在感染后11天（实验的最晚时间点），尽管存在中和抗体反应，但未发现病毒RNA载量和活病毒有明显下降。这也远远超出了临床和病毒血症阶段。这些结果对JEV的发病机制具有重要意义，并呼吁进一步开展侧重于猪体内病毒复制的细胞来源和持续时间的实验研究。
