Pseudorabies virus HLJ strain suppresses peripheral blood T and B lymphocytes in mice

Pseudorabies virus (PRV), responsible for pseudorabies, is one of the most important pathogen in swine industry. PRV infection suppresses interferon-β (IFN-β) and tumor necrosis factor-α (TNF-α) expression, which consequently results in an immune escape in the host.

In this study, distribution of peripheral blood T and B cell sub-populations was analyzed by flow cytometry after infecting mice with 1×10⁵ TCID₅₀ PRV.

We found that the levels of CD3⁺ T, CD4⁺ T and CD8⁺ T lymphocyte in infection group were significantly decreased at 24 hpi (p<0.01) and remained at a low level until 72 hpi compared to the control group. Interestingly, the levels of CD19⁺ T lymphocyte were significantly lower after 24 hpi (p<0.01) and lasted until 48 hpi, then increased sharply and then dropped at 96 hpi. Collectively, these results indicated that PRV infection could play a negative role in adaptive immunity in mice by decreasing the levels of B and T lymphocytes.