Comparative analyses of host responses upon infection with moderately virulent Classical swine fever virus in domestic pigs and wild boar

Virology Journal

Sandra Blome²  Jana Pietschmann²  Martin Beer²  Ulrike Blohm¹  Anja Petrov² 

[1] Institute of Immunology, Friedrich-Loeffler-Institut, Suedufer 10, 17493 Greifswald, Insel Riems, Germany;Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Suedufer 10, 17493 Greifswald, Insel Riems, Germany

关键词: Host factors;    Pathogenesis;    Host responses;    Classical swine fever virus;   

Others  :  1148769
DOI  :  10.1186/1743-422X-11-134

 received in 2014-04-06, accepted in 2014-07-22,  发布年份 2014

【 摘 要 】

Background

Classical swine fever (CSF) is one of the most important viral diseases of pigs. Clinical signs may vary from almost inapparent infection to a hemorrhagic fever like illness. Among the host factors leading to different disease courses are age, breed, and immune status. The aim of this study was to compare host responses of different pig breeds upon infection with a recent moderately virulent CSF virus (CSFV) strain, and to assess their impact on the clinical outcome and the efficiency of immune responses. To this means, two domestic pig types (German Landrace and hybrids), were compared to European wild boar. Along with clinical and pathological assessments and routine virological and serological methods, kinetics of immune-cellular parameters were evaluated.

Findings

All animals were susceptible to infection and despite clinical differences, virus could be detected in all infected animals to similar amounts. All but one animal developed an acute disease course, two landrace animals recovered after a transient infection. One wild boar got chronically infected. Changes in the percentages of lymphocyte subsets in peripheral blood did not show a clear correlation with the clinical outcome. High and early titers of neutralizing antibodies were especially detected in wild boar and German Landrace pigs.

Conclusions

While differences among breeds did not have the expected impact on course and outcome of CSFV infection, preload with facultative pathogens and even small differences in age seemed to be more relevant. Future studies will target the characterization of responses observed during different disease courses including cytokine reactions and further analyses of lymphocyte subsets.

【 授权许可】

   
2014 Petrov et al.; licensee BioMed Central Ltd.

【 图 表 】

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