Influenza A virus (IAV) infection leads to the formation of mucosal memory CD4 T cells that can protect the host. An in-depth understanding of the signals that shape memory cell development is required for more effective vaccine design. We have examined the formation of memory CD4 T cells in the lung following IAV infection of mice, characterizing changes to the lung landscape and immune cell composition.
View Article and Find Full Text PDFInterferon gamma (IFN) is a potent antiviral cytokine that can be produced by many innate and adaptive immune cells during infection. Currently, our understanding of which cells produce IFN and where they are located at different stages of an infection is limited. We have used reporter mice to investigate expression of mRNA in the lung and secondary lymphoid organs during and following influenza A virus (IAV) infection.
View Article and Find Full Text PDFSpillover events of avian influenza A viruses (IAVs) to humans could represent the first step in a future pandemic. Several factors that limit the transmission and replication of avian IAVs in mammals have been identified. There are several gaps in our understanding to predict which virus lineages are more likely to cross the species barrier and cause disease in humans.
View Article and Find Full Text PDFInt J Biochem Cell Biol
December 2022
The lung is frequently and repeatedly exposed to invading pathogens and thus requires constant immunosurveillance. Professional antigen presenting cells (APCs), including dendritic cells, engulf invading pathogens and present their peptides via major histocompatibility complexes (MHC) I and II, to CD8 or CD4 T cells. Epithelial cells and stromal cells (including fibroblasts) provide more than structural support, they are increasingly recognised as key players in the immune response, acting as non-professional APCs through interactions with antigen experienced T cells that migrate to the lung.
View Article and Find Full Text PDFCommunication between stromal and immune cells is essential to maintain tissue homeostasis, mount an effective immune response and promote tissue repair. This 'crosstalk' occurs in both the steady state and following a variety of insults, for example, in response to local injury, at sites of infection or cancer. What do we mean by crosstalk between cells? Reciprocal activation and/or regulation occurs between immune and stromal cells, by direct cell contact and indirect mechanisms, including the release of soluble cytokines.
View Article and Find Full Text PDFFibrosis is a common pathological feature of chronic disease. Deletion of the NF-κB subunit c-Rel limits fibrosis in multiple organs, although the mechanistic nature of this protection is unresolved. Using cell-specific gene-targeting manipulations in mice undergoing liver damage, we elucidate a critical role for c-Rel in controlling metabolic changes required for inflammatory and fibrogenic activities of hepatocytes and macrophages and identify Pfkfb3 as the key downstream metabolic mediator of this response.
View Article and Find Full Text PDFAm J Physiol Cell Physiol
December 2020
CXC chemokine receptor 3 (CXCR3) A and its IFN-inducible ligands CXCL9 and CXCL10 regulate vascular remodeling and fibroblast motility. IL-13 is a profibrotic cytokine implicated in the pathogenesis of inflammatory and fibroproliferative conditions. Previous work from our laboratory has shown that CXCR3A is negatively regulated by IL-13 and is necessary for the basal regulation of the IL-13 receptor subunit IL-13Rα2.
View Article and Find Full Text PDFObjectives: NF-κB regulates genes that control inflammation, cell proliferation, differentiation and survival. Dysregulated NF-κB signalling alters normal skin physiology and deletion of cRel limits bleomycin-induced skin fibrosis. This study investigates the role of cRel in modulating fibroblast phenotype in the context of SSc.
View Article and Find Full Text PDFSystemic Sclerosis (SSc) is an autoimmune idiopathic connective tissue disease, characterized by aberrant fibro-proliferative and inflammatory responses, causing fibrosis of multiple organs. In recent years the interactions between innate and adaptive immune cells with resident fibroblasts have been uncovered. Cross-talk between immune and stromal cells mediates activation of stromal cells to myofibroblasts; key cells in the pathophysiology of fibrosis.
View Article and Find Full Text PDFBiochim Biophys Acta Gene Regul Mech
October 2018
The NF-?B p50 subunit is an important regulator of inflammation, with recent experimental evidence to support it also having a tumor suppressor role. Classically, p50 functions in heterodimeric form with the RelA (p65) NF-?B subunit to activate inflammatory genes. However, p50 also forms homodimers which actively repress NF-?B-dependent inflammatory gene expression and exert an important brake on the inflammatory process.
View Article and Find Full Text PDFObjective: SSc is an autoimmune connective tissue disease that results in skin fibrosis and currently has no effective treatment. Epigenetic modifications have been described and these may be key in initiating and driving fibroblast activation. Among these epigenetic modifications methylation may be of central importance.
View Article and Find Full Text PDFAm J Physiol Lung Cell Mol Physiol
November 2018
Idiopathic pulmonary fibrosis (IPF), a chronic progressive interstitial pneumonia, is characterized by excessive fibroproliferation. Key effector cells in IPF are myofibroblasts that are recruited from three potential sources: resident fibroblasts, fibrocytes, and epithelial cells. We hypothesized that IPF myofibroblasts from different sources display unique gene expression differences and distinct functional characteristics.
View Article and Find Full Text PDFEpithelial to mesenchymal cell transition (EMT), whereby fully differentiated epithelial cells transition to a mesenchymal phenotype, has been implicated in the pathogenesis of idiopathic pulmonary fibrosis (IPF). CXCR3 and its ligands are recognized to play a protective role in pulmonary fibrosis. In this study, we investigated the presence and extent of EMT and CXCR3 expression in human IPF surgical lung biopsies and assessed whether CXCR3 and its ligand CXCL9 modulate EMT in alveolar epithelial cells.
View Article and Find Full Text PDFPulmonary fibrosis is a progressive and fatal disease that involves the remodeling of the distal airspace and the lung parenchyma, which results in compromised gas exchange. The median survival time once diagnosed is less than three years. Interleukin (IL)-13 has been shown to play a role in a number of inflammatory and fibrotic diseases.
View Article and Find Full Text PDFIdiopathic pulmonary fibrosis (IPF) is a progressive disease characterized by fibrosis and abnormal vascularity. IL-13, a profibrotic cytokine that plays a role in IPF, functions through the Jak/STAT pathway after binding to the IL-13 receptor α1 (IL-13Rα1)/IL-4Rα complex. IL-13 also binds to IL-13Rα2, which has been thought to function as a nonsignaling decoy receptor, although possible signaling roles of this receptor have been proposed.
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