Porcine Circovirus Modulates Swine Influenza Virus Replication in Pig Tracheal Epithelial Cells and Porcine Alveolar Macrophages

Abstract

The pathogenesis of porcine circovirus type 2b (PCV2b) and swine influenza A virus (SwIV) during co-infection in swine respiratory cells is poorly understood. To elucidate the impact of PCV2b/SwIV co-infection, newborn porcine tracheal epithelial cells (NPTr) and immortalized porcine alveolar macrophages (iPAM 3D4/21) were co-infected with PCV2b and SwIV (H1N1 or H3N2 genotype). Viral replication, cell viability and cytokine mRNA expression were determined and compared between single-infected and co-infected cells. Finally, 3′mRNA sequencing was performed to identify the modulation of gene expression and cellular pathways in co-infected cells. It was found that PCV2b significantly decreased or improved SwIV replication in co-infected NPTr and iPAM 3D4/21 cells, respectively, compared to single-infected cells. Interestingly, PCV2b/SwIV co-infection synergistically up-regulated IFN expression in NPTr cells, whereas in iPAM 3D4/21 cells, PCV2b impaired the SwIV IFN induced response, both correlating with SwIV replication modulation. RNA-sequencing analyses revealed that the modulation of gene expression and enriched cellular pathways during PCV2b/SwIV H1N1 co-infection is regulated in a cell-type-dependent manner. This study revealed different outcomes of PCV2b/SwIV co-infection in porcine epithelial cells and macrophages and provides new insights on porcine viral co-infections pathogenesis.

DUSP1 mRNA modulation during porcine circovirus type 2 and porcine reproductive and respiratory syndrome virus co-infection regulates viruses replication

“…The NPTr-CD163 cells, which were previously obtained ( Provost et al., 2017 ), were cultured in Minimum Essential Medium (MEM) (Invitrogen Corporation, GibcoBRL, ON, Canada) supplemented with 10 % fetal bovine serum (FBS) (Wisent Bioproducts, QC, Canada), 1 mM sodium pyruvate, 10 I.U./mL of penicillin, 10 μg/mL of streptomycin and 250 g/L amphotericin B solution (Wisent Bioproducts, QC, Canada), as previously described ( Burgher Pulgaron et al., 2023 ). MARC-145 cells (ATCC CRL-12,231) were maintained as previously described ( Lévesque et al., 2014 ).…”