Effect of porcine circovirus type 2 (PCV2) on the function of splenic CD11c+ dendritic cells in mice

Abstract

Porcine circovirus-associated disease (PCVAD) caused by porcine circovirus type 2 (PCV2) is an important disease in the global pig industry. Dendritic cells (DCs) are the primary immune cells capable of initiating adaptive immune responses as well as major target cells of PCV2. To determine whether PCV2 affects the immune functions of DCs, we evaluated the expression of endocytosis and co-stimulatory molecules on DCs (CD11c) from PCV2-infected mouse spleen by flow cytometry (FCM). We also analyzed the main cytokines secreted by DCs (CD11c) and activation of CD4 and CD8 T cells by DCs (CD11c) through measurement of cytokine secretion, using ELISA. Compared with control mice, PCV2 did not affect the endocytic activity of DCs but it significantly enhanced TNF-α secretion and markedly decreased IFN-α secretion. Subsets of CD40, MHCII CD40 and CD137L CD86 DCs did not increase obviously, but MHCII CD40 and CD137L CD80/CD86 DCs increased significantly in PCV2-infected mouse spleen. Under the stimulation of DCs from PCV2-infected mouse, secretion of IFN-γ by CD4 and CD8 T cells and of IL-12 by CD8 T cells was significantly lower than in control mice, while secretion of IL-4 by CD4 T cells was remarkably higher. These results indicate that PCV2 modulates cytokine secretion and co-stimulatory molecule expression of DCs, and alters activation of CD4 and CD8 T cells by DCs. The immunomodulatory effects of PCV2 on DCs might be related to the host's immune dysfunction and persistent infection with this virus.

Cathepsin S Is Involved in Th17 Differentiation Through the Upregulation of IL-6 by Activating PAR-2 after Systemic Exposure to Lipopolysaccharide from Porphyromonas gingivalis

“…The CD11c + cells could be inducted as splenic DCs recently (Owens et al, 2012; Bao et al, 2015; Wang et al, 2017). Three mice in each group were anesthetized and perfused transcardially with PBS, and then the spleen samples were cut into small pieces.…”

Detection and molecular characterization of canine circovirus circulating in northeastern China during 2014–2016

“…Circoviruses have been confirmed to be associated with vesicular and hemorrhagic and enteric diseases as well as low body weight, poor body condition, and feathering disorders in birds [6,7]. An immunosuppressive effect has been observed in infections with PCV2, psittacine beak and feather disease virus, pigeon circovirus, and duck circovirus [8,9].…”

Mouse models of porcine circovirus 2 infection

“…MHCII + CD40 − and CD137L − CD80 + /CD86 + DCs increased significantly in PCV2‐infected mouse spleens . Secretion of IFN‐γ by CD4 + and CD8 + T cells and of IL‐12 by CD8 + T cells was significantly lower in PCV2‐infected mice, while secretion of IL‐4 by CD4 + T cells was remarkably higher . These results indicate that PCV2 modulates cytokine secretion and costimulatory molecule expression by DCs and alters the activation of CD4 + and CD8 + T cells by DCs, which might be related to the host's immune dysfunction and persistent infection with PCV2 .…”

“…Compared with control mice, PCV2 infection significantly enhanced TNF‐α secretion and markedly decreased IFN‐α secretion . MHCII + CD40 − and CD137L − CD80 + /CD86 + DCs increased significantly in PCV2‐infected mouse spleens .…”

“…Compared with control mice, PCV2 infection significantly enhanced TNF‐α secretion and markedly decreased IFN‐α secretion . MHCII + CD40 − and CD137L − CD80 + /CD86 + DCs increased significantly in PCV2‐infected mouse spleens . Secretion of IFN‐γ by CD4 + and CD8 + T cells and of IL‐12 by CD8 + T cells was significantly lower in PCV2‐infected mice, while secretion of IL‐4 by CD4 + T cells was remarkably higher .…”