Type I Interferon Signaling Increases Versican Expression and Synthesis in Lung Stromal Cells During Influenza Infection

Abstract

Versican, a chondroitin sulfate proteoglycan, is an essential component of the extracellular matrix (ECM) in inflammatory lung disease. Versican’s potential as an immunomodulatory molecule makes it a promising therapeutic target for controlling host immune responses in the lungs. To establish changes to versican expression and accumulation during influenza A viral pneumonia, we document the temporal and spatial changes to versican mRNA and protein in concert with pulmonary inflammatory cell infiltration. These studies were performed in the lungs of wild-type C57BL6/J mice on days 3, 6, 9, and 12 post-infection with influenza A virus using immunohistochemistry, in situ hybridization, and quantitative digital pathology. Using duplex in situ hybridization, we demonstrate that type I interferon signaling contributes significantly to versican expression in lung stromal cells. Our findings show that versican is a type I interferon–stimulated gene in pulmonary fibroblasts and pericytes in the context of viral pneumonia. These data also provide a guide for future studies to determine the role of versican in the pulmonary immune response to influenza infection:

Pathway Expression Analysis

“…For example, R-HSA-74713 is a mediator of insulin signaling events and the effect of influenza on insulin is discussed by Ohno et al in 22 . Additionally, the pathway detected in the 4 study experiment at the 25 to 32 hour time bin, R-HSA-3595177, is involved in the synthesis of chondroitin sulfate which has been shown to be involved with pulmonary immune response to influenza infection by Brune et al 23 . Many of these other top pathways may have a similar indirect link to respiratory viruses.…”

Regulation of Versican Expression in Macrophages is Mediated by Canonical Type I Interferon Signaling via ISGF3

“…al., demonstrated that type I Ifn signaling increases versican expression and synthesis in lung stromal cells of C57BL6/J wild-type mice during influenza infection. (Brune et al, 2021) However, it is not known which arm of type I Ifn signaling is invoked in stromal cells in response to influenza – the formation of ISGF3 with anti-viral consequences or Stat1 homodimers which bind to gamma-activated sequences (GASs) to induce pro-inflammatory genes. Studies in B6.Rosa26-Cre ERT+/- Vcan fl/fl (Vcan -/- ) mice with a global deletion of versican, when treated with tamoxifen, showed decreased recovery of inflammatory cells in BALF following treatment with poly(I:C).…”

“…(Chang et al, 2017) We also observed that peak induction of versican in the lungs of mice infected with influenza A virus (IAV) correlated with peak induction of Ifn-β, and that versican expression was significantly attenuated in the lungs of IAV-infected mice lacking functional type I Ifn receptors (Ifnar1 -/- ) compared to IAV-infected wild-type mice. (Brune et al, 2021) Using dual in situ hybridization, versican expression was found to be decreased both in CD68 + myeloid cells and in PDGFRβ + stromal cells in the lungs of IAV-infected Ifnar1 -/- versus wild-type mice. Taken together, these findings support a role for type I Ifn signaling in regulating versican expression in both myeloid and stromal cells.…”

“…(Andersson-Sjoland et al, 2015; Ayars et al, 2013; Bensadoun et al, 1996, 1997; Huang et al, 1999; Kim et al, 2009; Merrilees et al, 2008; Merrilees et al, 2004; Morales et al, 2011; Ricciardelli et al, 2009; Said et al, 2012; Weitoft et al, 2014) Versican is synthesized by multiple types of cells, including embryonic stem cells, epithelial, endothelial, stromal and neural cells, as well as by leukocytes. (Bode-Lesniewska et al, 1996; Brune et al, 2021; Chang et al, 2014; Hatano et al, 2012; Henderson & Copp, 1998; Kellar et al, 2021; LeBaron et al, 1992; Schonherr et al, 1991; Sotoodehnejadnematalahi et al, 2015) In vitro and in vivo studies have shown that this synthesis occurs in response to a variety of stimuli, including cytokines, growth factors, and agonists that bind to pattern recognition receptors. The roles of versican in these responses appear to be context-dependent, with both pro- and anti-inflammatory properties depending on the agonist, cellular involvement, kinetics of the immune response, and disease process.…”

Pathway expression analysis

“…Insulin signaling is related to the influenza virus because the influenza virus impairs insulin signaling and down-regulates the expression of genes in the insulin pathway which supports our detection of the 28 , 29 . Additionally, R-HSA-3595177 is involved in the synthesis of chondroitin sulfate which has been shown to be involved with pulmonary immune response to influenza infection by Brune et al 30 .…”