scholarly journals Effects of Pseudomonas aeruginosa on CFTR chloride secretion and the host immune response

2017 ◽  
Vol 312 (4) ◽  
pp. C357-C366 ◽  
Author(s):  
Bruce A. Stanton
Keyword(s):  
Immune Response ◽  
Pseudomonas Aeruginosa ◽  
Lung Function ◽  
Mucociliary Clearance ◽  
Fluid Layer ◽  
Opportunistic Pathogen ◽  
Host Immune Response ◽  
Liquid Volume ◽  
Bacterial Antigen ◽  
Surface Liquid

In the healthy lung the opportunistic pathogen, Pseudomonas aeruginosa, is rapidly eliminated by mucociliary clearance, a process that is dependent on the activity of the CFTR anion channel that, in concert with a number of other transport proteins, regulates the volume and composition of the periciliary surface liquid. This fluid layer is essential to enable cilia to clear pathogens from the lungs. However, in cystic fibrosis (CF), mutations in the CFTR gene reduce Cl− and [Formula: see text] secretion, thereby decreasing periciliary surface liquid volume and mucociliary clearance of bacteria. In CF this leads to persistent infection with the opportunistic pathogen, P. aeruginosa, which is the cause of reduced lung function and death in ~95% of CF patients. Others and we have conducted studies to elucidate the effects of P. aeruginosa on wild-type and Phe508del-CFTR Cl− secretion as well as on the host immune response. These studies have demonstrated that Cif (CFTR inhibitory factor), a virulence factor secreted by P. aeruginosa, is associated with reduced lung function in CF and induces the ubiquitination and degradation of wt-CFTR as well as TAP1, which plays a key role in viral and bacterial antigen presentation. Cif also enhances the degradation of Phe508del-CFTR that has been rescued by ORKAMBI, a drug approved for CF patients homozygous for the Phe508del-CFTR mutation, thereby reducing drug efficacy. This review is based on the Hans Ussing Distinguished Lecture at the 2016 Experimental Biology Meeting given by the author.

scholarly journals Hypertonic Saline in Treatment of Pulmonary Disease in Cystic Fibrosis

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Emer P. Reeves ◽  
Kevin Molloy ◽  
Kerstin Pohl ◽  
Noel G. McElvaney
Keyword(s):  
Cystic Fibrosis ◽  
Hypertonic Saline ◽  
Mucociliary Clearance ◽  
Inflammatory Cells ◽  
Liquid Volume ◽  
Airway Surface Liquid ◽  
Beneficial Effects ◽  
Therapeutic Benefits ◽  
Surface Liquid ◽  
Subsequent Failure

The pathogenesis of lung disease in cystic fibrosis is characterised by decreased airway surface liquid volume and subsequent failure of normal mucociliary clearance. Mucus within the cystic fibrosis airways is enriched in negatively charged matrices composed of DNA released from colonizing bacteria or inflammatory cells, as well as F-actin and elevated concentrations of anionic glycosaminoglycans. Therapies acting against airway mucus in cystic fibrosis include aerosolized hypertonic saline. It has been shown that hypertonic saline possesses mucolytic properties and aids mucociliary clearance by restoring the liquid layer lining the airways. However, recent clinical and bench-top studies are beginning to broaden our view on the beneficial effects of hypertonic saline, which now extend to include anti-infective as well as anti-inflammatory properties. This review aims to discuss the described therapeutic benefits of hypertonic saline and specifically to identify novel models of hypertonic saline action independent of airway hydration.

TesG is a type I secretion effector of Pseudomonas aeruginosa that suppresses the host immune response during chronic infection

2019 ◽  
Vol 4 (3) ◽  
pp. 459-469 ◽  
Author(s):  
Kelei Zhao ◽  
Wujiao Li ◽  
Jing Li ◽  
Teng Ma ◽  
Kailun Wang ◽  
...  
Keyword(s):  
Immune Response ◽  
Pseudomonas Aeruginosa ◽  
Chronic Infection ◽  
Host Immune Response ◽  
Type I

scholarly journals The Manganese-Responsive Transcriptional Regulator MumR Protects Acinetobacter baumannii from Oxidative Stress

2019 ◽  
Vol 88 (3) ◽  
Author(s):  
Erin R. Green ◽  
Lillian J. Juttukonda ◽  
Eric P. Skaar
Keyword(s):  
Oxidative Stress ◽  
Immune Response ◽  
Acinetobacter Baumannii ◽  
Transcriptional Regulator ◽  
Opportunistic Pathogen ◽  
Host Immune Response ◽  
Gamma Aminobutyric Acid ◽  
Content Type ◽  
Growth And Survival ◽  
Rapid Acquisition

ABSTRACT Acinetobacter baumannii is an emerging opportunistic pathogen that primarily infects critically ill patients in nosocomial settings. Because of its rapid acquisition of antibiotic resistance, infections caused by A. baumannii have become extremely difficult to treat, underlying the importance of identifying new antimicrobial targets for this pathogen. Manganese (Mn) is an essential nutrient metal required for a number of bacterial processes, including the response to oxidative stress. Here, we show that exogenous Mn can restore A. baumannii viability in the presence of reactive oxygen species (ROS). This restoration is not dependent on the high-affinity Nramp family Mn transporter, MumT, as a ΔmumT mutant is no more sensitive to hydrogen peroxide (H2O2) killing than wild-type A. baumannii. However, mumR, which encodes the transcriptional regulator of mumT, is critical for growth and survival in the presence of H2O2, suggesting that MumR regulates additional genes that contribute to H2O2 resistance. RNA sequencing revealed a role for mumR in regulating the activity of a number of metabolic pathways, including two pathways, phenylacetate and gamma-aminobutyric acid catabolism, which were found to be important for resisting killing by H2O2. Finally, ΔmumR exhibited reduced fitness in a murine model of pneumonia, indicating that MumR-regulated gene products are crucial for protection against the host immune response. In summary, these results suggest that MumR facilitates resistance to the host immune response by activating a transcriptional program that is critical for surviving both Mn starvation and oxidative stress.

scholarly journals 48 The humoral immune response against Pseudomonas aeruginosa correlates with decreased lung function in a cohort of Brazilian CF patients

2016 ◽  
Vol 15 ◽  
pp. S63-S64
Author(s):  
R.M. Mauch ◽  
C.L. Rossi ◽  
T.B. Aiello ◽  
M.T. Nolasco da Silva ◽  
C.C.S. Gomez ◽  
...  
Keyword(s):  
Immune Response ◽  
Pseudomonas Aeruginosa ◽  
Lung Function ◽  
Humoral Immune Response ◽  
Humoral Immune

scholarly journals Pseudomonas aeruginosa PA14 produces R-bodies, extendable protein polymers with roles in host colonization and virulence

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Bryan Wang ◽  
Yu-Cheng Lin ◽  
Alejandro Vasquez-Rifo ◽  
Jeanyoung Jo ◽  
Alexa Price-Whelan ◽  
...  
Keyword(s):  
Immune Response ◽  
Pseudomonas Aeruginosa ◽  
Opportunistic Pathogen ◽  
Structural Genes ◽  
Protein Polymers ◽  
Bacterial Endosymbionts ◽  
Stochastic Expression ◽  
Body Production ◽  
And Control ◽  
Insight Into

AbstractR-bodies are long, extendable protein polymers formed in the cytoplasm of some bacteria; they are best known for their role in killing of paramecia by bacterial endosymbionts. Pseudomonas aeruginosa PA14, an opportunistic pathogen of diverse hosts, contains genes (referred to as the reb cluster) with potential to confer production of R-bodies and that have been implicated in virulence. Here, we show that products of the PA14 reb cluster associate with R-bodies and control stochastic expression of R-body structural genes. PA14 expresses reb genes during colonization of plant and nematode hosts, and R-body production is required for full virulence in nematodes. Analyses of nematode ribosome content and immune response indicate that P. aeruginosa R-bodies act via a mechanism involving ribosome cleavage and translational inhibition. Our observations provide insight into the biology of R-body production and its consequences during P. aeruginosa infection.

The In Vitro Antibiofilm Activity of Water Leaf Extract of Papaya (Carica papaya L.) against Pseudomonas aeruginosa

2017 ◽  
Vol 2 (3) ◽  
pp. 150-163
Author(s):  
Ekajayanti Kining ◽  
Syamsul Falah ◽  
Novik Nurhidayat
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Contact Time ◽  
Cell Attachment ◽  
Water Extract ◽  
Opportunistic Pathogen ◽  
Bacterial Biofilm ◽  
Antibiofilm Activity ◽  
Bacterial Survival ◽  
Optimum Conditions

Pseudomonas aeruginosa is one of opportunistic pathogen forming bacterial biofilm. The biofilm sustains the bacterial survival and infections. This study aimed to assess the activity of water extract of papaya leaves on inhibition of cells attachment, growth and degradation of the biofilm using crystal violet (CV) biofilm assay. Research results showed that water extract of papaya leaves contains alkaloids, tanins, flavonoids, and steroids/terpenoids and showed antibacterial activity and antibiofilm against P. aeruginosa. Addition of extract can inhibit the cell attachment and was able to degrade the biofilm of 40.92% and 48.058% respectively at optimum conditions: extract concentration of 25% (v/v), temperature 37.5 °C and contact time 45 minutes. With a concentration of 25% (v/v), temperature of 50 °C and the contact time of 3 days, extract of papaya leaves can inhibit the growth of biofilms of 39.837% v/v.

Sign in / Sign up

Export Citation Format

Share Document