scholarly journals Global gene expression patterns and induction of innate immune response in human laryngeal epithelial cells in response toAcinetobacter baumanniiouter membrane protein A

2008 ◽  
Vol 54 (1) ◽  
pp. 45-52 ◽  
Author(s):  
Soon Ae Kim ◽  
Sung Min Yoo ◽  
Sung Hee Hyun ◽  
Chul Hee Choi ◽  
So Young Yang ◽  
...  
2006 ◽  
Vol 291 (2) ◽  
pp. C218-C230 ◽  
Author(s):  
Terry E. Machen

The lack of functional cystic fibrosis (CF) transmembrane conductance regulator (CFTR) in the apical membranes of CF airway epithelial cells abolishes cAMP-stimulated anion transport, and bacteria, eventually including Pseudomonas aeruginosa, bind to and accumulate in the mucus. Flagellin released from P. aeruginosa triggers airway epithelial Toll-like receptor 5 and subsequent NF-κB signaling and production and release of proinflammatory cytokines that recruit neutrophils to the infected region. This response has been termed hyperinflammatory because so many neutrophils accumulate; a response that damages CF lung tissue. We first review the contradictory data both for and against the idea that epithelial cells exhibit larger-than-normal proinflammatory signaling in CF compared with non-CF cells and then review proposals that might explain how reduced CFTR function could activate such proinflammatory signaling. It is concluded that apparent exaggerated innate immune response of CF airway epithelial cells may have resulted not from direct effects of CFTR on cellular signaling or inflammatory mediator production but from indirect effects resulting from the absence of CFTRs apical membrane channel function. Thus, loss of Cl−, HCO3−, and glutathione secretion may lead to reduced volume and increased acidification and oxidation of the airway surface liquid. These changes concentrate proinflammatory mediators, reduce mucociliary clearance of bacteria and subsequently activate cellular signaling. Loss of apical CFTR will also hyperpolarize basolateral membrane potentials, potentially leading to increases in cytosolic [Ca2+], intracellular Ca2+, and NF-κB signaling. This hyperinflammatory effect of CF on intracellular Ca2+and NF-κB signaling would be most prominently expressed during exposure to both P. aeruginosa and also endocrine, paracrine, or nervous agonists that activate Ca2+signaling in the airway epithelia.


2006 ◽  
Vol 20 (4) ◽  
Author(s):  
Nigel Keith Stepto ◽  
Timothy John Burton ◽  
Therese Griersmith ◽  
David Powell ◽  
Benedict James Canny

2019 ◽  
Author(s):  
Carly D. Kenkel ◽  
Veronique J.L. Mocellin ◽  
Line K. Bay

AbstractThe mechanisms resulting in the breakdown of the coral symbiosis once the process of bleaching has been initiated remain unclear. Distinguishing symbiont loss from the abiotic stress response may shed light on the cellular and molecular pathways involved in each process. This study examined physiological changes and global gene expression patterns associated with white patch syndrome (WPS) in P. lobata, which manifests in localized bleaching independent of thermal stress. In addition, a meta-analysis of global gene expression studies in other corals and anemones was used to contrast differential regulation as a result of abiotic stress from expression patterns correlated with symbiotic state. Symbiont density, chlorophyll a content, holobiont productivity, instant calcification rate, and total host protein content were uniformly reduced in WPS relative to healthy tissue. While expression patterns associated with WPS were secondary to fixed effects of source colony, specific functional enrichments suggest that the viral infection putatively giving rise to this condition affects symbiont rather than host cells. The meta-analysis revealed that expression patterns in WPS-affected tissues were significantly correlated with prior studies examining short-term thermal stress responses. This correlation was independent of symbiotic state, as the strongest correlations were found between WPS adults and both symbiotic adult and aposymbiotic coral larvae experiencing thermal stress, suggesting that the majority of expression changes reflect a non-specific stress response. Across studies, the magnitude and direction of expression change among particular functional enrichments suggests unique responses to stressor duration, and highlights unique responses to bleaching in an anemone model which engages in a non-obligate symbiosis.


2020 ◽  
pp. 2001584
Author(s):  
Jason Girkin ◽  
Su-Ling Loo ◽  
Camille Esneau ◽  
Steven Maltby ◽  
Francesca Mercuri ◽  
...  

Research questionAssessment of whether TLR2 activation boosts the innate immune response to rhinovirus infection, as a treatment strategy for virus-induced respiratory diseases.MethodsWe employed treatment with a novel TLR2 agonist (INNA-X) prior to rhinovirus infection in mice, and INNA-X treatment in differentiated human bronchial epithelial cells derived from asthmatic-donors. We assessed viral load, immune cell recruitment, cytokines, type I and III IFN production, as well as the lung tissue and epithelial cell immune transcriptome.ResultsWe show in vivo, that a single INNA-X treatment induced innate immune priming characterised by low-level IFN-λ, Fas ligand, chemokine expression and airway lymphocyte recruitment. Treatment 7-days before infection significantly reduced lung viral load, increased IFN-β/λ expression and inhibited neutrophilic inflammation. Corticosteroid treatment enhanced the anti-inflammatory effects of INNA-X. Treatment 1-day before infection increased expression of 190 lung tissue immune genes. This tissue gene expression signature was absent with INNA-X treatment 7-days before infection, suggesting an alternate mechanism, potentially via establishment of immune cell-mediated mucosal innate immunity. In vitro, INNA-X treatment induced a priming response defined by upregulated IFN-λ, chemokine and anti-microbial gene expression that preceded an accelerated response to infection enriched for NF-κB-regulated genes and reduced viral loads, even in epithelial cells derived from asthmatic donors with intrinsic delayed anti-viral immune response.ConclusionAirway epithelial cell TLR2 activation induces prolonged innate immune priming, defined by early NF-κB activation, IFN-λ expression and lymphocyte recruitment. This response enhanced anti-viral innate immunity and reduced virus-induced airway inflammation.


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