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Biology subjects

Finney, G. E.

Publications and source records attributed to Finney, G. E..

3 recordsLinked to original sources

Human hepatic stellate cells orchestrate the accumulation and function of CD103+ tissue-resident CD8+ T-cells in liver fibrosis

Tissue-resident memory cells (TRM) contribute to protective and pathogenic responses in the liver, yet precisely how hepatic TRM adapt and integrate cues from the underlying stroma and extracellular matrix (ECM) in chronic liver disease (CLD) has yet to be fully defined. Here we describe a role for activated myofibroblast-like hepatic stellate cells (HSCs) in the accumulation and in situ localisation of CD8+ TRM in the CLD liver. Activated HSCs drive a program of tissue residence in activated, tissue-infiltrating CD8+ T-cells in a TGF{beta}-dependent manner. We show upregulation of CD103, ECM-binding integrins and adhesion molecules driven by TGF{beta} which together contribute to the sequestration of TRM within the ECM-rich fibrotic niche. Ex vivo, hepatic CD103+ TRM correlate with the extent of ECM deposited, express an altered repertoire of co-stimulatory and co-inhibitory receptors, transcriptional regulators of cellular exhaustion and produce less proinflammatory mediators upon TCR engagement in CLD than in health. Through expression of several co-inhibitory ligands, we further demonstrate the potential for activated HSCs to acquire an immunomodulatory phenotype and limit the capacity of CD103+ TRM to produce anti-viral and anti-tumour mediators upon antigen encounter. Finally, we demonstrate that strategies to block such regulatory pathways, including the PD1:PD-L1/PD-L2 axis, have the potential to restore the antigen-specific effector function of tissue-compartmentalised CD103+ TRM and thus contribute to improving the effectiveness of local immunosurveillance in CLD. One Sentence Summary: Activated hepatic stellate cells characteristic of liver fibrosis orchestrate an accumulation of a CD103+ TRM population with a reduced capacity for antigen-specific effector function in human CLD.

immunology↗

Lung structural cell dynamics are altered by influenza virus infection experience leading to rapid immune protection following viral re-challenge

Lung structural cells, including epithelial cells and fibroblasts, form barriers against pathogens and trigger immune responses following infections such as influenza A virus. This response leads to the recruitment of innate and adaptive immune cells required for viral clearance. Some of these recruited cells remain within the lung following infection and contribute to enhanced viral control following subsequent infections. There is growing evidence that structural cells can also display long-term changes following infection or insults. Here we investigate long-term changes to mouse lung epithelial cells, fibroblasts, and endothelial cells following influenza virus infection and find that all three cell types maintain an imprint of the infection, particularly in genes associated with communication with T cells. Lung epithelial cells from IAV-infected mice display functional changes by more rapidly controlling influenza virus than cells from naive animals. This rapid anti-viral response and increased expression of molecules required to communicate with T cells demonstrates sustained and enhanced functions following infection. These data suggest lung structural cells could be effective targets for vaccines to boost durable protective immunity. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=135 SRC="FIGDIR/small/604410v5_ufig1.gif" ALT="Figure 1"> View larger version (55K): org.highwire.dtl.DTLVardef@2774e0org.highwire.dtl.DTLVardef@6a39e6org.highwire.dtl.DTLVardef@1ff5863org.highwire.dtl.DTLVardef@103df12_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LILung epithelial cells, fibroblasts, and blood endothelial cells maintain an inflammatory imprint of influenza A virus (IAV) infection for at least 40 days post-infection. C_LIO_LIIn vivo re-infection leads to a more spatially restricted anti-viral response compared to primary IAV-infected animals. C_LIO_LIT cells are not required for enhanced viral control early after re-infection in vivo C_LIO_LIEx vivo lung epithelial cells from IAV-infected mice more rapidly control IAV than cells from naive animals in the absence of immune cells. C_LI

immunology↗

Triphasic production of IFNγ by innate and adaptive lymphocytes following influenza A virus infection

Interferon gamma (IFN{gamma}) 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{gamma} and where they are located at different stages of an infection are limited. We have used reporter mice to investigate in vivo expression of IFN{gamma} in the lung and secondary lymphoid organs during and following influenza A virus (IAV) infection. We observed a triphasic production of IFN{gamma} expression. Unconventional T cells and innate lymphoid cells, particularly NK cells, were the dominant producers of early IFN{gamma}, while CD4 and CD8 T cells were the main producers by day 10 post-infection. Following viral clearance, some memory CD4 and CD8 T cells continued to produce IFN{gamma} in the lungs and draining lymph node. Interestingly, IFN{gamma} production by lymph node Natural Killer (NK), NKT and innate lymphoid 1 cells also continued to be above naive levels, suggesting memory-like phenotypes for these cells. Analysis of the localisation of IFN{gamma}+ memory CD4 and CD8 T cells demonstrated that cytokine+ T cells were located near airways and in the lung parenchyma. Following a second IAV challenge, lung IAV specific CD8 T cells rapidly increased their expression of IFN{gamma} while CD4 T cells in the draining lymph node increased their IFN{gamma} response. Together, these data suggest that IFN{gamma} production fluctuates based on cellular source and location, both of which could impact subsequent immune responses.

immunology↗