scholarly journals The quorum sensing com system regulates pneumococcal colonisation and invasive disease in a pseudo-stratified airway tissue model

2021 ◽  
Author(s):  
Christian R. Kahlert ◽  
Susanne Nigg ◽  
Lucas Onder ◽  
Ronald Dijkman ◽  
Liliane Diener ◽  
...  
Keyword(s):  
Quorum Sensing ◽  
Ex Vivo ◽  
Pneumococcal Infection ◽  
Invasive Disease ◽  
Confocal Imaging ◽  
Post Inoculation ◽  
Airway Epithelial ◽  
Ex Vivo Model ◽  
Virulent Phenotype ◽  
Lung Biopsies

Streptococcus pneumoniae (Spn) colonises respiratory epithelia but can also invade lung cells causing pneumonia. We developed an ex vivo model with human airway epithelial (HAE) cells harvested from lung biopsies to study Spn colonisation and translocation. Flow-cytometry, confocal imaging and electron microscopy studies identified the epithelial lineage with signs of differentiation (beating cilia, mucus, and tight junctions). HAE cells were challenged with Spn wild-type TIGR4 (wtSpn) or its isogenic ΔcomC quorum sensing-deficient mutant. ΔcomC mutant colonised significantly less than wtSpn at 6 h post-inoculation but at significantly higher levels at 19 h and 30 h. Translocation correlated inversely with colonisation density. Transepithelial electric resistance (TEER) decreased after pneumococcal infection and correlated with increased translocation for both strains. Confocal imaging illustrated colocalisation of intracellular Spn with both cilia and zonulin-1 and prominent microcolony formation with wtSpn but disintegration of microcolony structures over time with ΔcomC mutant. ΔcomC caused a more pronounced release of both zonulin-1 and lactate dehydrogenase into the supernatant at later time points than wtSpn, suggesting that cytotoxicity is likely not the mechanism leading to translocation. There was a density- and time-dependent increase of inflammatory cytokines from human HAE cells infected with ΔcomC compared with wtSpn, including increased levels of the NLRP3 inflammasome-related IL-18. In conclusion, our experiments indicate that ComC system allows a higher organisational level of population structure resulting in microcolony formation, increased early colonisation and subsequent translocation. We propose that ComC inactivation unleashes a very different and possibly more virulent phenotype that merits further investigation.

scholarly journals Zinc deficiency as a codeterminant for airway epithelial barrier dysfunction in an ex vivo model of COPD

2017 ◽  
Vol Volume 12 ◽  
pp. 3503-3510 ◽  
Author(s):  
Eugene Roscioli ◽  
Hubertus Jersmann ◽  
Susan Lester ◽  
Arash Badiei ◽  
Andrew Fon ◽  
...  
Keyword(s):  
Zinc Deficiency ◽  
Ex Vivo ◽  
Epithelial Barrier ◽  
Airway Epithelial ◽  
Barrier Dysfunction ◽  
Ex Vivo Model ◽  
Epithelial Barrier Dysfunction

1849: Systematic Evaluation of 21μm Thulium Laser Device for Treatment of Benign Prostatic Enlargement in an Ex-VIVO Model

2007 ◽  
Vol 177 (4S) ◽  
pp. 614-614 ◽  
Author(s):  
Gunnar Wendt-Nordahl ◽  
Stefanie Huckele ◽  
Patrick Honeck ◽  
Peter Aiken ◽  
Thomas Knoll ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Systematic Evaluation ◽  
Thulium Laser ◽  
Laser Device ◽  
Benign Prostatic Enlargement ◽  
Ex Vivo Model ◽  
Prostatic Enlargement

Porcine small intestine, a good ex vivo model to investigate absorption and metabolism of natural products

2017 ◽  
Author(s):  
J Houriet ◽  
YE Arnold ◽  
C Petit ◽  
YN Kalia ◽  
JL Wolfender
Keyword(s):  
Natural Products ◽  
Small Intestine ◽  
Ex Vivo ◽  
Ex Vivo Model

Effects of Two Different Doses of Hirudin on APTT, Determined with Eight Different Reagents

1995 ◽  
Vol 73 (02) ◽  
pp. 219-222 ◽  
Author(s):  
Manuel Monreal ◽  
Luis Monreal ◽  
Rafael Ruiz de Gopegui ◽  
Yvonne Espada ◽  
Ana Maria Angles ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Anticoagulant Activity ◽  
Subcutaneous Administration ◽  
In Vitro Study ◽  
Ex Vivo Model ◽  
Suitable Candidate ◽  
Significant Prolongation ◽  
High Doses ◽  
Different Doses

SummaryThe APTT has been considered the most suitable candidate to monitor the anticoagulant activity of hirudin. However, its use is hampered by problems of standardization, which make the results heavily dependent on the responsiveness of the reagent used. Our aim was to investigate if this different responsiveness of different reagents when added in vitro is to be confirmed in an ex vivo study.Two different doses of r-hirudin (CGP 39393), 0.3 mg/kg and 1 mg/kg, were administered subcutaneously to 20 New Zealand male rabbits, and the differences in prolongation of APTT 2 and 12 h later were compared, using 8 widely used commercial reagents. All groups exhibited a significant prolongation of APTT 2 h after sc administration of hirudin, both at low and high doses. But this prolongation persisted 12 h later only when the PTTa reagent (Boehringer Mannheim) was used. In general, hirudin prolonged the APTT most with the silica- based reagents.In a further study, we compared the same APTT reagents in an in vitro study in which normal pooled plasma was mixed with increasing amount of hirudin. We failed to confirm a higher sensitivity for silica- containing reagents. Thus, we conclude that subcutaneous administration of hirudin prolongs the APTT most with the silica-based reagents, but this effect is exclusive for the ex vivo model.

EMR+: Vorstellung einer neuen endoskopischen Resektionsmethode im ex-vivo Model

2019 ◽  
Author(s):  
RF Knoop ◽  
E Wedi ◽  
V Ellenrieder ◽  
A Neesse ◽  
S Kunsch
Keyword(s):  
Ex Vivo ◽  
Ex Vivo Model

Anti-Inflammatory Effects of Novel Standardized Platelet Rich Plasma Releasates on Knee Osteoarthritic Chondrocytes and Cartilage in vitro

2019 ◽  
Vol 20 (11) ◽  
pp. 920-933 ◽  
Author(s):  
Lucía Gato-Calvo ◽  
Tamara Hermida-Gómez ◽  
Cristina R. Romero ◽  
Elena F. Burguera ◽  
Francisco J. Blanco
Keyword(s):  
Gene Expression ◽  
Ex Vivo ◽  
Platelet Rich Plasma ◽  
Cartilage Explants ◽  
Ex Vivo Model ◽  
Chondrocyte Viability ◽  
Platelet Concentration ◽  
The Absolute ◽  
Anti Inflammatory

Background: Platelet Rich Plasma (PRP) has recently emerged as a potential treatment for osteoarthritis (OA), but composition heterogeneity hampers comparison among studies, with the result that definite conclusions on its efficacy have not been reached. Objective: 1) To develop a novel methodology to prepare a series of standardized PRP releasates (PRP-Rs) with known absolute platelet concentrations, and 2) To evaluate the influence of this standardization parameter on the anti-inflammatory properties of these PRP-Rs in an in vitro and an ex vivo model of OA. Methods: A series of PRPs was prepared using the absolute platelet concentration as the standardization parameter. Doses of platelets ranged from 0% (platelet poor plasma, PPP) to 1.5·105 platelets/µl. PRPs were then activated with CaCl2 to obtain releasates (PRP-R). Chondrocytes were stimulated with 10% of each PRP-R in serum-free culture medium for 72 h to assess proliferation and viability. Cells were co-stimulated with interleukin (IL)-1β (5 ng/ml) and 10% of each PRP-R for 48 h to determine the effects on gene expression, secretion and intra-cellular content of common markers associated with inflammation, catabolism and oxidative stress in OA. OA cartilage explants were co-stimulated with IL-1β (5 ng/ml) and 10% of either PRP-R with 0.75·105 platelets/µl or PRP-R with 1.5·105 platelets/µl for 21 days to assess matrix inflammatory degradation. Results: Chondrocyte viability was not affected, and proliferation was dose-dependently increased. The gene expression of all pro-inflammatory mediators was significantly and dose-independently reduced, except for that of IL-1β and IL-8. Immunoblotting corroborated this effect for inducible NO synthase (NOS2). Secreted matrix metalloproteinase-13 (MMP-13) was reduced to almost basal levels by the PRP-R from PPP. Increasing platelet dosage led to progressive loss to this anti-catabolic ability. Safranin O and toluidine blue stains supported the beneficial effect of low platelet dosage on cartilage matrix preservation. Conclusion: We have developed a methodology to prepare PRP releasates using the absolute platelet concentration as the standardization parameter. Using this approach, the composition of the resulting PRP derived product is independent of the donor initial basal platelet count, thereby allowing the evaluation of its effects objectively and reproducibly. In our OA models, PRP-Rs showed antiinflammatory, anti-oxidant and anti-catabolic properties. Platelet enrichment could favor chondrocyte proliferation but is not necessary for the above effects and could even be counter-productive.

scholarly journals Anti-pseudomonad Activity of Manuka Honey and Antibiotics in a Specialized ex vivo Model Simulating Cystic Fibrosis Lung Infection

2019 ◽  
Vol 10 ◽  
Author(s):  
Aled E. L. Roberts ◽  
Lydia C. Powell ◽  
Manon F. Pritchard ◽  
David W. Thomas ◽  
Rowena E. Jenkins
Keyword(s):  
Cystic Fibrosis ◽  
Ex Vivo ◽  
Lung Infection ◽  
Cystic Fibrosis Lung ◽  
Manuka Honey ◽  
Ex Vivo Model

scholarly journals 231 Impact of Brachyspira hyodysentariae on intestinal function and integrity

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 116-116
Author(s):  
Emma T Helm ◽  
Susanne J Lin ◽  
Nicholas Gabler ◽  
Eric R Burrough
Keyword(s):  
Ex Vivo ◽  
Potato Starch ◽  
Nutrient Digestibility ◽  
High Morbidity ◽  
Post Inoculation ◽  
Intestinal Function ◽  
Treatment Groups ◽  
Intestinal Integrity ◽  
Beet Pulp ◽  
The Impact

Abstract Swine dysentery (SD) induced by Brachyspira hyodysentariae (Bhyo) causes colitis and mucohemorrhagic diarrhea in grow-finish pigs, however little is known about the physiological changes that occur to the gastrointestinal tract during Bhyo infection. Thus, the objective of this study was to evaluate the impact of a Bhyo challenge on intestinal function and integrity of pigs fed two divergent diets. A total of 36 Bhyo negative gilts (24.3 ± 3.6 kg BW) were selected and assigned to one of three treatment groups (n=12 pigs/trt): 1) Bhyo negative, 20% DDGS diet (CON), 2) Bhyo challenged, 20% DDGS diet (DDGS), and 3) Bhyo challenged, 10% DDGS, 5% beet pulp and 5% resistant potato starch diet (RS). Pigs were fed diets 21 days prior to challenge and on days post inoculation (dpi) 0 and 1, pigs were inoculated with Bhyo or sham. Fecal samples were collected for ATTD and pigs were euthanized for colon collection within 72 hours of initial observation of clinical SD, or at the end of the study (dpi 10-16). Tissues were assessed for ex vivo measures of intestinal integrity and mitochondrial function. The challenge resulted in high morbidity, with 88% of DDGS and RS pigs developing clinical SD. Colon transepithelial resistance was increased in DDGS pigs compared with CON and RS pigs (P=0.005), and colon macromolecule permeability was reduced in both DDGS and RS pigs compared with CON pigs (P=0.006), likely due to mucoid discharge. Colonic mitochondrial oxygen consumption was not impacted by treatment (P >0.10). Further, ATTD of DM, OM, N, and GE were reduced in DDGS pigs compared with CON pigs (P< 0.001), whilst nutrient digestibility was not reduced in RS pigs. Taken together, these data show Bhyo does not appear to reduce ex vivo colonic integrity. Further, the RS diet may reduce severity of a Bhyo challenge.

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