ERK MAPK signaling pathway regulates porcine circovirus type 2 replication in peripheral blood mononuclear cells

Abstract

Porcine circovirus type 2 (PCV2) is one of the most important swine viral diseases in Thailand and worldwide.
While the interaction between PCV2 and pig immune system has been largely explored, the mechanisms by which
PCV2 replicates in porcine immune cells and alters host cellular signaling pathways remain incomplete. In this study,
extracellular regulated kinase (ERK) phosphorylation form was shown to slightly increase in PCV2-infected peripheral
blood mononuclear cells (PBMCs) at 48 hr post infection. To demonstrate the role of ERK MAPK signaling, PBMCs
were divided into three groups including control, virus, and virus with the mitogen-activated protein kinase (MEK)
specific inhibitor, U0126, to prevent ERK phosphorylation. U0126 at 10 µM completely inhibited ERK activation in the
porcine PBMCs at 48 and 72 hr. Interestingly, the inhibition of ERK MAPK significantly impaired PCV2 replication in
the PBMCs. In summary, our results unraveled the role of ERK MAPK signaling during PCV2 replication in porcine
immune cells. These findings provide important information on how PCV2 interacts with host cells and influences host
immune response.