Delivery of CFTR by adenoviral vector to cystic fibrosis mouse lung in a model of chronicPseudomonas aeruginosalung infection

2004 ◽  
Vol 286 (4) ◽  
pp. L717-L726 ◽  
Author(s):  
Anna M. van Heeckeren ◽  
Abraham Scaria ◽  
Mark D. Schluchter ◽  
Thomas W. Ferkol ◽  
Samuel Wadsworth ◽  
...  

In cystic fibrosis (CF) there is an excessive inflammatory response to lung infections with Pseudomonas aeruginosa, which causes significant morbidity and mortality. Mice deficient in the cystic fibrosis conductance transmembrane regulator homolog ( Cftr) have exaggerated production of proinflammatory cytokines in epithelial lining fluid and increased mortality in response to chronic bronchopulmonary infection with mucoid P. aeruginosa, compared with infected wild-type littermates. Whether delivery of CFTR to CF airways by an adenoviral vector (Ad2/CFTR-16) decreases cytokine production and mortality in response to chronic bronchopulmonary infection with mucoid P. aeruginosa was tested. CF mice [stock Cftrtm1Unc-TgN(FABPCFTR)#Jaw] were anesthetized with isoflurane and inoculated intranasally with either Ad2/CFTR-16, diluent (sucrose), or empty vector (Ad2/EV). Two weeks later, mice were anesthetized with 2.5% Avertin and inoculated transtracheally with P. aeruginosa-laden agarose beads (PA M57–15). The cumulative 10-day survival of mice pretreated with Ad2/CFTR-16 was significantly higher compared with mice pretreated with sucrose but not significantly higher than mice pretreated with Ad2/EV. After adjusting for differences in experiment, we found weight loss at 3 days for mice treated with Ad2/CFTR-16 to be significantly less than for the sucrose- or Ad2/EV-treated groups. However, cytokine responses were similar in all groups 3 days after infection. In conclusion, the observed survival advantage of adenoviral delivery of CFTR to the CF lung may be due either to CFTR expression or possibly to proinflammatory effects of the adenoviral vector, or both.

2004 ◽  
Vol 72 (3) ◽  
pp. 1479-1486 ◽  
Author(s):  
Anna M. van Heeckeren ◽  
Mark Schluchter ◽  
Lintong Xue ◽  
Juan Alvarez ◽  
Steven Freedman ◽  
...  

ABSTRACT In cystic fibrosis, a recessive genetic disease caused by defects in the cystic fibrosis conductance regulator (CFTR), the main cause of death is lung infection and inflammation. Nutritional deficits have been proposed to contribute to the excessive host inflammatory response in both humans and Cftr-knockout mice. Cftr-knockout mice and gut-corrected Cftr-knockout mice expressing human CFTR primarily in the gut were challenged with Pseudomonas aeruginosa-laden agarose beads; they responded similarly with respect to bronchoalveolar lavage cell counts and levels of the acute-phase cytokines tumor necrosis factor alpha, interleukin-1β (IL-1β), and IL-6. Wild-type mice fed the liquid diet used to prevent intestinal obstruction in Cftr-knockout mice had inflammatory responses to P. aeruginosa-laden agarose beads similar to those of wild-type mice fed an enriched solid diet, so dietary effects are unlikely to account for differences between wild-type mice and mice with cystic fibrosis. Finally, since cystic fibrosis patients and Cftr-knockout mice have an imbalance in fatty acids (significantly lower-than-normal levels of docosahexaenoic acid), the effects of specific supplementation with docosahexaenoic acid of wild-type and Cftr-knockout mice on their inflammatory responses to P. aeruginosa-laden agarose beads were tested. There were no significant differences (P = 0.35) in cumulative survival rates between Cftr-knockout mice and wild-type mice provided with either the liquid diet Peptamen or Peptamen containing docosahexaenoic acid. In conclusion, diet and docosahexaenoic acid imbalances alone are unlikely to explain the differences in the host response to lung infections with mucoid P. aeruginosa between mice with cystic fibrosis and their wild-type counterparts.


2014 ◽  
Vol 117 (3) ◽  
pp. 284-288 ◽  
Author(s):  
Thomas Jaecklin ◽  
Julia Duerr ◽  
Hailu Huang ◽  
Mahroukh Rafii ◽  
Christine E. Bear ◽  
...  

The activity of arginase is increased in airway secretions of patients with cystic fibrosis (CF). Downstream products of arginase activity may contribute to CF lung disease. We hypothesized that pulmonary arginase expression and activity would be increased in mouse models of CF and disproportionally increased in CF mice with Pseudomonas aeruginosa pneumonia. Expression of arginase isoforms in lung tissue was quantified with reverse transcriptase-PCR in naive cystic fibrosis transmembrane conductance regulator ( Cftr)-deficient mice and β-epithelial sodium channel-overexpressing [β-ENaC-transgenic (Tg)] mice. An isolated lung stable isotope perfusion model was used to measure arginase activity in Cftr-deficient mice before and after intratracheal instillation of Pseudomonas aeruginosa. The expression of arginase-2 in lung was increased in adult Cftr-deficient animals and in newborn β-ENaC-Tg. Arginase-1 lung expression was normal in Cftr-deficient and in newborn β-ENaC-Tg mice, but was increased in β-ENaC-Tg mice at age 1, 3, and 6 wk. Arginase activity was significantly higher in lung (5.0 ± 0.7 vs. 3.2 ± 0.3 nmol·−1·h−1, P = 0.016) and airways (204.6 ± 49.8 vs. 79.3 ± 17.2 nmol·−1·h−1, P = 0.045) of naive Cftr-deficient mice compared with sex-matched wild-type littermate controls. Infection with Pseudomonas aeruginosa resulted in a far greater increase in lung arginase activity in Cftr-deficient mice (10-fold) than in wild-type controls (6-fold) ( P = 0.01). This is the first ex vivo characterization of arginase expression and activity in CF mouse lung and airways. Our data show that pulmonary arginase expression and activity is increased in CF mice, especially with Pseudomonas aeruginosa infections.


2020 ◽  
Vol 88 (9) ◽  
Author(s):  
Kristen J. Brao ◽  
Brendan P. Wille ◽  
Joshua Lieberman ◽  
Robert K. Ernst ◽  
Mark E. Shirtliff ◽  
...  

ABSTRACT The opportunistic pathogen Pseudomonas aeruginosa is responsible for much of the morbidity and mortality associated with cystic fibrosis (CF), a condition that predisposes patients to chronic lung infections. P. aeruginosa lung infections are difficult to treat because P. aeruginosa adapts to the CF lung, can develop multidrug resistance, and can form biofilms. Despite the clinical significance of P. aeruginosa, modeling P. aeruginosa infections in CF has been challenging. Here, we characterize Scnn1b-transgenic (Tg) BALB/c mice as P. aeruginosa lung infection models. Scnn1b-Tg mice overexpress the epithelial Na+ channel (ENaC) in their lungs, driving increased sodium absorption that causes lung pathology similar to CF. We intranasally infected Scnn1b-Tg mice and wild-type littermates with the laboratory P. aeruginosa strain PAO1 and CF clinical isolates and then assessed differences in bacterial clearance, cytokine responses, and histological features up to 12 days postinfection. Scnn1b-Tg mice carried higher bacterial burdens when infected with biofilm-grown rather than planktonic PAO1; Scnn1b-Tg mice also cleared infections more slowly than their wild-type littermates. Infection with PAO1 elicited significant increases in proinflammatory and Th17-linked cytokines on day 3. Scnn1b-Tg mice infected with nonmucoid early CF isolates maintained bacterial burdens and mounted immune responses similar to those of PAO1-infected Scnn1b-Tg mice. In contrast, Scnn1b-Tg mice infected with a mucoid CF isolate carried high bacterial burdens, produced significantly more interleukin 1β (IL-1β), IL-13, IL-17, IL-22, and KC, and showed severe immune cell infiltration into the bronchioles. Taken together, these results show the promise of Scnn1b-Tg mice as models of early P. aeruginosa colonization in the CF lung.


2019 ◽  
Vol 18 ◽  
pp. S25
Author(s):  
H. Cao ◽  
H. Ouyang ◽  
O. Laselva ◽  
C. Bartlett ◽  
C.E. Bear ◽  
...  

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 146
Author(s):  
Hafij Al Mahmud ◽  
Jiwasmika Baishya ◽  
Catherine A. Wakeman

Cystic fibrosis (CF) is a genetic disease frequently associated with chronic lung infections caused by a consortium of pathogens. It is common for auxotrophy (the inability to biosynthesize certain essential metabolites) to develop in clinical isolates of the dominant CF pathogen Pseudomonas aeruginosa, indicating that the CF lung environment is replete in various nutrients. Many of these nutrients are likely to come from the host tissues, but some may come from the surrounding polymicrobial community within the lungs of CF patients as well. To assess the feasibility of nutrient exchange within the polymicrobial community of the CF lung, we selected P. aeruginosa and Staphylococcus aureus, two of the most prevalent species found in the CF lung environment. By comparing the polymicrobial culture of wild-type strains relative to their purine auxotrophic counterparts, we were able to observe metabolic complementation occurring in both P. aeruginosa and S. aureus when grown with a purine-producing cross-species pair. While our data indicate that some of this complementation is likely derived from extracellular DNA freed by lysis of S. aureus by the highly competitive P. aeruginosa, the partial complementation of S. aureus purine deficiency by P. aeruginosa demonstrates that bidirectional nutrient exchange between these classic competitors is possible.


2002 ◽  
Vol 36 (3) ◽  
pp. 291-312 ◽  
Author(s):  
A. M. van Heeckeren ◽  
M. D. Schluchter

The animal model of chronic bronchopulmonary infection using agarose beads laden with Pseudomonas aeruginosa is frequently utilized in cystic fibrosis research, though it is challenging to perform it in mice. This paper reports the most successful methods for the creation of this model. Transtracheal insertion of a 22 G 1" over-the-needle intravenous catheter to preferentially inoculate the right mainstem bronchus using tribromoethanol anaesthesia administered i.p. was better for a successful surgical outcome compared, respectively, to the use of a 27 G ½" needle, bilateral inoculation or an anaesthetic cocktail of xylazine, acepromazine and ketamine administered i.p. Bilateral infection was associated with higher mortality, greater weight loss and higher levels of bronchoalveolar cytokine concentration, compared to mice infected primarily in the right lung. Mucoid clinical strain PA M57-15 was preferred since mucoid clinical strain PA 2192 led to comparatively more severe lesions and higher mortality. Using the same operator for a given task reduced the variability inherent in this model, illustrated using outcome measures such as gross lung pathology. The response of mice inoculated with P. aeruginosa-laden agarose beads was characterized by bronchopulmonary inflammation, high production of cytokines, and significant weight loss; whereas the response to infection with free-living bacteria was characterized by pneumonia, lower production of cytokines and weight loss. The use of free P. aeruginosa pre-mixed with sterile agarose beads may be considered as an alternative to the use of P. aeruginosa-laden agarose beads, since the histopathological features were similar, though further characterization is needed to evaluate its utility as an adequate model of cystic fibrosis.


1995 ◽  
Vol 269 (1) ◽  
pp. C226-C233 ◽  
Author(s):  
V. Casavola ◽  
R. J. Turner ◽  
C. Guay-Broder ◽  
K. A. Jacobson ◽  
O. Eidelman ◽  
...  

The selective A1-adenosine-receptor antagonist, 8-cyclopentyl-1,3-dipropylxanthine (CPX), has been reported to activate Cl- efflux from cystic fibrosis cells, such as pancreatic CFPAC-1 and lung IB3 cells bearing the cystic fibrosis transmembrane regulator(delta F508) mutation, but has little effect on the same process in cells repaired by transfection with wild-type cystic fibrosis transmembrane regulator (O. Eidelman, C. Guay-Broder, P. J. M. van Galen, K. A. Jacobson, C. Fox, R. J. Turner, Z. I. Cabantchik, and H. B. Pollard. Proc. Natl. Acad. Sci. USA 89: 5562-5566, 1992). We report here that CPX downregulates Na+/H+ exchange activity in CFPAC-1 cells but has a much smaller effect on cells repaired with the wild-type gene. CPX also mildly decreases resting intracellular pH. In CFPAC-1 cells, this downregulation is dependent on the presence of adenosine, since pretreatment of the cells with adenosine deaminase blocks the CPX effect. We also show that, by contrast, CPX action on these cells does not lead to alterations in intracellular free Ca2+ concentration. We conclude that CPX affects pH regulation in CFPAC-1 cells, probably by antagonizing the tonic action of endogenous adenosine.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 577
Author(s):  
Douweh Leyla Gbian ◽  
Abdelwahab Omri

The eradication of Pseudomonas aeruginosa in cystic fibrosis patients has become continuously difficult due to its increased resistance to treatments. This study assessed the efficacy of free and liposomal gentamicin and erythromycin, combined with Phenylalanine arginine beta-naphthylamide (PABN), a broad-spectrum efflux pump inhibitor, against P. aeruginosa isolates. Liposomes were prepared and characterized for their sizes and encapsulation efficiencies. The antimicrobial activities of formulations were determined by the microbroth dilution method. Their activity on P. aeruginosa biofilms was assessed, and the effect of sub-inhibitory concentrations on bacterial virulence factors, quorum sensing (QS) signals and bacterial motility was also evaluated. The average diameters of liposomes were 562.67 ± 33.74 nm for gentamicin and 3086.35 ± 553.95 nm for erythromycin, with encapsulation efficiencies of 13.89 ± 1.54% and 51.58 ± 2.84%, respectively. Liposomes and PABN combinations potentiated antibiotics by reducing minimum inhibitory and bactericidal concentrations by 4–32 fold overall. The formulations significantly inhibited biofilm formation and differentially attenuated virulence factor production as well as motility. Unexpectedly, QS signal production was not affected by treatments. Taken together, the results indicate that PABN shows potential as an adjuvant of liposomal macrolides and aminoglycosides in the management of lung infections in cystic fibrosis patients.


Sign in / Sign up

Export Citation Format

Share Document