J Vet Sci.  2021 Mar;22(2):e20. 10.4142/jvs.2021.22.e20.

Establishment of inflammatory model induced by Pseudorabies virus infection in mice

• Ren CZ
• Hu WY
• Zhang JW
• Wei YY
• Yu ML
• Hu TJ

• KMID: 2514463
• DOI: http://doi.org/10.4142/jvs.2021.22.e20

Abstract

Background
Pseudorabies virus (PRV) infection leads to high mortality in swine. Despite extensive efforts, effective treatments against PRV infection are limited. Furthermore, the inflammatory response induced by PRV strain GXLB-2013 is unclear.
Objectives
Our study aimed to investigate the inflammatory response induced by PRV strain GXLB-2013, establish an inflammation model to elucidate the pathogenesis of PRV infection further, and develop effective drugs against PRV infection.
Methods
Kunming mice were infected intramuscularly with medium, LPS, and different doses of PRV-GXLB-2013. Viral spread and histopathological damage to brain, spleen, and lung were determined at 7 days post-infection (dpi). Immune organ indices, levels of reactive oxygen species (ROS), nitric oxide (NO), and inflammatory cytokines, as well as levels of activity of COX-2 and iNOS were determined at 4, 7, and 14 dpi.
Results
At 10⁵ –10⁶ TCID₅₀ PRV produced obviously neurological symptoms and 100% mortality in mice. Viral antigens were detectable in kidney, heart, lung, liver, spleen, and brain. In addition, inflammatory injuries were apparent in brain, spleen, and lung of PRVinfected mice. Moreover, PRV induced increases in immune organ indices, ROS and NO levels, activity of COX-2 and iNOS, and the content of key pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, tumor necrosis factor-α, interferon-γ and MCP-1. Among the tested doses, 10 2 TCID 50 of PRV produced a significant inflammatory mediator increase.
Conclusions
An inflammatory model induced by PRV infection was established in mice, and 10² TCID₅₀ PRV was considered as the best concentration for the establishment of the model.

Keyword

Pseudorabies virus; inflammatory; cytokines; mice