Matricellular Protein SPARCL1 Regulates Blood Vessel Integrity and Antagonizes Inflammatory Bowel Disease

Abstract Background The understanding of vascular plasticity is key to defining the role of blood vessels in physiologic and pathogenic processes. In the present study, the impact of the vascular quiescence marker SPARCL1 on angiogenesis, capillary morphogenesis, and vessel integrity was evaluated. Methods Angiogenesis was studied using the metatarsal test, an ex vivo model of sprouting angiogenesis. In addition, acute and chronic dextran sodium sulfate colitis models with SPARCL1 knockout mice were applied. Results This approach indicated that SPARCL1 inhibits angiogenesis and supports vessel morphogenesis and integrity. Evidence was provided that SPARCL1-mediated stabilization of vessel integrity counteracts vessel permeability and inflammation in acute and chronic dextran sodium sulfate colitis models. Structure-function analyses of purified SPARCL1 identified the acidic domain of the protein necessary for its anti-angiogenic activity. Conclusions Our findings inaugurate SPARCL1 as a blood vessel–derived anti-angiogenic molecule required for vessel morphogenesis and integrity. SPARCL1 opens new perspectives as a vascular marker of susceptibility to colitis and as a therapeutic molecule to support blood vessel stability in this disease.

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Precision cut lung slices: an ex vivo model for assessing the impact of immunomodulatory therapeutics on lung immune responses

Archives of Toxicology ◽

10.1007/s00204-021-03096-y ◽

2021 ◽

Author(s):

Guanghui Liu ◽

Linnea Särén ◽

Helena Douglasson ◽

Xiao-Hong Zhou ◽

Per M. Åberg ◽

...

Keyword(s):

Immune Responses ◽

Ex Vivo ◽

Ex Vivo Model ◽

Precision Cut Lung Slices ◽

The Impact

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Experimental Models to Study COVID-19 Effect in Stem Cells

Cells ◽

10.3390/cells10010091 ◽

2021 ◽

Vol 10 (1) ◽

pp. 91

Author(s):

Rishi Man Chugh ◽

Payel Bhanja ◽

Andrew Norris ◽

Subhrajit Saha

Keyword(s):

Stem Cells ◽

Ex Vivo ◽

Drug Efficacy ◽

Cell Loss ◽

Experimental Models ◽

Model Systems ◽

Virus Infectivity ◽

Ex Vivo Model ◽

Global Pandemic ◽

The Impact

The new strain of coronavirus (severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)) emerged in 2019 and hence is often referred to as coronavirus disease 2019 (COVID-19). This disease causes hypoxic respiratory failure and acute respiratory distress syndrome (ARDS), and is considered as the cause of a global pandemic. Very limited reports in addition to ex vivo model systems are available to understand the mechanism of action of this virus, which can be used for testing of any drug efficacy against virus infectivity. COVID-19 induces tissue stem cell loss, resulting inhibition of epithelial repair followed by inflammatory fibrotic consequences. Development of clinically relevant models is important to examine the impact of the COVID-19 virus in tissue stem cells among different organs. In this review, we discuss ex vivo experimental models available to study the effect of COVID-19 on tissue stem cells.

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Corticosteroids alter alveolar macrophage control of Lichtheimia corymbifera spores in an ex vivo mouse model

Medical Mycology ◽

10.1093/mmy/myaa104 ◽

2020 ◽

Author(s):

Kévin Brunet ◽

François Arrivé ◽

Jean-Philippe Martellosio ◽

Isabelle Lamarche ◽

Sandrine Marchand ◽

...

Keyword(s):

Mouse Model ◽

Alveolar Macrophage ◽

Oxidative Burst ◽

Ex Vivo ◽

Fungal Growth ◽

Invasive Infection ◽

Ex Vivo Model ◽

Lichtheimia Corymbifera ◽

The Impact

Abstract Alveolar macrophages (AM) are the first-line lung defense against Mucorales in pulmonary mucormycosis. Since corticosteroid use is a known risk factor for mucormycosis, the aim of this study was to describe the role of corticosteroids on AM capacities to control Lichtheimia corymbifera spore growth using a new ex vivo model. An in vivo mouse model was developed to determine the acetate cortisone dose able to trigger pulmonary invasive infection. Then, in the ex vivo model, male BALB/c mice were pretreated with the corticosteroid regimen triggering invasive infection, before AM collection through bronchoalveolar lavage. AMs from corticosteroid-treated mice and untreated control AMs were then exposed to L. corymbifera spores in vitro (ratio 1:5). AM control of fungal growth, adherence/phagocytosis, and oxidative burst were assessed using optical densities by spectrophotometer, flow cytometry, and 2', 7'-dichlorofluoresceine diacetate fluorescence, respectively. Cortisone acetate at 500 mg/kg, at D-3 and at D0, led to pulmonary invasive infection at D3. Co-incubated spores and AMs from corticosteroid-treated mice had significantly higher absorbance (fungal growth) than co-incubated spores and control AMs, at 24 h (P = .025), 36 h (P = .004), and 48 h (P = .001). Colocalization of spores with AMs from corticosteroid-treated mice was significantly lower than for control AMs (7.6 ± 1.9% vs 22.3 ± 5.8%; P = .003), reflecting spore adherence and phagocytosis inhibition. Finally, oxidative burst was significantly increased when control AMs were incubated with spores (P = 0.029), while corticosteroids hampered oxidative burst from treated AMs (P = 0.321). Corticosteroids enhanced fungal growth of L. corymbifera through AM phagocytosis inhibition and burst oxidative decrease in our ex vivo model. Lay Summary The aim of this study was to describe the impact of corticosteroids on alveolar macrophage (AM) capacities to control Mucorales growth in a new murine ex vivo model. Corticosteroids enhanced fungal growth of L. corymbifera through AM phagocytosis inhibition and burst oxidative decrease.

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A New Ex Vivo Model to Evaluate the Hair Protective Effect of a Biomimetic Exopolysaccharide against Water Pollution

Cosmetics ◽

10.3390/cosmetics7040078 ◽

2020 ◽

Vol 7 (4) ◽

pp. 78

Author(s):

Claire Tubia ◽

Alfonso Fernández-Botello ◽

Jan Dupont ◽

Eni Gómez ◽

Jérôme Desroches ◽

...

Keyword(s):

Water Pollution ◽

Heavy Metals ◽

Heavy Metal ◽

Adverse Effects ◽

Inductively Coupled Plasma ◽

Ex Vivo ◽

Polluted Water ◽

Ex Vivo Model ◽

Fiber Damage ◽

The Impact

As an external appendage, hair is exposed to multiple stresses of different origins such as particles and gases in air, or heavy metals and chemicals in water. So far, little research has addressed the impact of water pollution on hair. The present study describes a new ex vivo model that allowed us to document the adverse effects of water pollutants on the structure of hair proteins, as well as the protective potential of active cosmetic ingredients derived from a biomimetic exopolysaccharide (EPS). The impact of water pollution was evaluated on hair from a Caucasian donor repeatedly immersed in heavy metal-containing water. Heavy metal retention in and on hair was then quantified using Inductively Coupled Plasma Spectrometry (ICP/MS). The adverse effects of heavy metals on the internal structure of hair and its prevention by the EPS were assessed through measurement of keratin birefringence. Notably, the method allows the monitoring of the organization of keratin fibers and therefore the initial change on it in order to modulate the global damage in the hair. Results revealed an increasing amount of lead, cadmium and copper, following multiple exposures to polluted water. In parallel, the structure of keratin was also altered with exposures. However, heavy metal-induced keratin fiber damage could be prevented in the presence of the tested EPS, avoiding more drastic hair problems, such as lack of shine, or decrease in strength, due to damage accumulation.

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The effect of algal polysaccharides laminarin and fucoidan on colonic pathology, cytokine gene expression and Enterobacteriaceae in a dextran sodium sulfate-challenged porcine model

Journal of Nutritional Science ◽

10.1017/jns.2016.4 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 15

Author(s):

C. J. O'Shea ◽

J. V. O'Doherty ◽

J. J. Callanan ◽

D. Doyle ◽

K. Thornton ◽

...

Keyword(s):

Body Weight ◽

Sodium Sulfate ◽

Basal Diet ◽

Proximal Colon ◽

Dextran Sodium Sulfate ◽

Mrna Abundance ◽

Cytokine Gene Expression ◽

Distilled Water ◽

The Impact ◽

Algal Polysaccharides

AbstractThe algal polysaccharides laminarin (LAM) and fucoidan (FUC) have potent anti-inflammatory activities in the gastrointestinal tract. Our objective was to examine the impact of prior consumption of LAM and/or FUC on pathology and inflammation following a dextran sodium sulfate (DSS) challenge in pigs. Pigs (n 7/group) were assigned to one of five experimental groups for 56 d. From 49–55 d, distilled water or DSS was administered intragastrically. The experimental groups were: (1) basal diet + distilled water (control); (2) basal diet + DSS (DSS); (3) basal diet + FUC + DSS (FUC + DSS); (4) basal diet + LAM + DSS (LAM + DSS); and (5) basal diet + LAM + FUC + DSS (LAMFUC + DSS). The DSS group had decreased body-weight gain (P < 0·05) and serum xylose (P < 0·05), and increased proximal colon pathology score (P < 0·05), diarrhoeal score (P < 0·001) and colonic Enterobacteriaceae (P < 0·05) relative to the control group. The FUC + DSS (P < 0·01), LAM + DSS (P < 0·05) and LAMFUC + DSS (P < 0·05) groups had improved diarrhoeal score, and the LAMFUC + DSS (P < 0·05) group had improved body weight relative to the DSS group. The FUC + DSS group (P < 0·001), LAM + DSS group (P < 0·05) and LAMFUC + DSS group (P < 0·001) had lower IL-6 mRNA abundance relative to the DSS group. The LAM + DSS group had reduced Enterobacteriaceae in proximal colon digesta relative to the DSS group (P < 0·05). In conclusion, FUC or a combination of FUC and LAM improved body-weight loss, diarrhoeal scores and clinical variables associated with a DSS challenge in pigs, in tandem with a reduction in colonic IL-6 mRNA abundance.

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Impact of Glycosylation and Species Origin on the Uptake and Permeation of IgGs through the Nasal Airway Mucosa

Pharmaceutics ◽

10.3390/pharmaceutics12111014 ◽

2020 ◽

Vol 12 (11) ◽

pp. 1014

Author(s):

Simone Ladel ◽

Frank Maigler ◽

Johannes Flamm ◽

Patrick Schlossbauer ◽

Alina Handl ◽

...

Keyword(s):

Nasal Mucosa ◽

Ex Vivo ◽

Human Cell Line ◽

Potential Interaction ◽

Primary Cells ◽

Wild Type ◽

Ex Vivo Model ◽

Human Igg ◽

Olfactory Tissue ◽

The Impact

Although we have recently reported the involvement of neonatal Fc receptor (FcRn) in intranasal transport, the transport mechanisms are far from being elucidated. Ex vivo porcine olfactory tissue, primary cells from porcine olfactory epithelium (OEPC) and the human cell line RPMI 2650 were used to evaluate the permeation of porcine and human IgG antibodies through the nasal mucosa. IgGs were used in their wild type and deglycosylated form to investigate the impact of glycosylation. Further, the expression of FcRn and Fc-gamma receptor (FCGR) and their interaction with IgG were analyzed. Comparable permeation rates for human and porcine IgG were observed in OEPC, which display the highest expression of FcRn. Only traces of porcine IgGs could be recovered at the basolateral compartment in ex vivo olfactory tissue, while human IgGs reached far higher levels. Deglycosylated human IgG showed significantly higher permeation in comparison to the wild type in RPMI 2650 and OEPC, but insignificantly elevated in the ex vivo model. An immunoprecipitation with porcine primary cells and tissue identified FCGR2 as a potential interaction partner in the nasal mucosa. Glycosylation sensitive receptors appear to be involved in the uptake, transport, but also degradation of therapeutic IgGs in the airway epithelial layer.

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Impact of hypoxia on immune cells in human atherosclerotic plaques

European Heart Journal ◽

10.1093/ehjci/ehaa946.3800 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

D Vorobyeva ◽

A Lebedeva ◽

A Elizarova ◽

E Maryukhnich ◽

V Gontarenko ◽

...

Keyword(s):

T Cells ◽

T Cell Activation ◽

Cell Activation ◽

Ex Vivo ◽

Atherosclerotic Plaques ◽

Funding Source ◽

Ex Vivo Model ◽

Activation Markers ◽

Hypoxic Conditions ◽

The Impact

Abstract Background Inflammation plays a major role in atherosclerotic plaques' progression and was shown to be associated with the formation of hypoxic areas within the plaques. However, the data about the impact of hypoxia on atherosclerosis are contradictory, in part due to inadequacy of in vitro and animal models to reproduce faithfully the complexity of human atherosclerotic plaques. Purpose The aim of this study was to investigate the effect of hypoxia on immune status in the ex vivo system of human atherosclerotic plaques. Methods We collected 25 atherosclerotic plaques from patients undergoing carotid endarterectomy, cut plaques into ring-shaped slices and cultured them for 24 hours at the liquid/air interface on collagen sponges under hypoxic (2% O2) and normoxic (12% O2) conditions. After 24 hours we evaluated T-cell activation status within plaques according to the presence of membrane activation markers by means of multiparametric flow cytometry and the activity of cytokine production using xMAP technology. Results We found that CD8 T cells from human atherosclerotic plaques cultured under hypoxic conditions compared to normoxic conditions have a decreased expression of CD69 activation marker (42.7 [34.3; 50.9]% vs 53.8 [33.3; 63.3]%, n=10, p=0.047) and lower level of CD69 and HLA-DR coexpression (16.0 [10.5; 22.3] vs 22.6 [11.3; 28.2], n=10, p=0.02). CD4 T cells did not show any significant changes in expression of activation markers under hypoxia. Hypoxic conditions also resulted in a reduced IL-10 production (104.2 [53.8; 170.9] vs 235.2 [158.5; 335.3] pg/100 mg of tissue, n=20, p=0.0001) and increased VEGF production (116.1 [79.8; 253.5] vs 89.9 [71.1; 148.8] pg/100 mg of tissue, n=20, p=0.033). Conclusions Our results indicate that hypoxia causes a decrease in the activity of cytotoxic T cells and increases stimuli for angiogenesis within the human atherosclerotic plaques. The established ex vivo model of human atherosclerotic plaques culture under hypoxia enables further studies of the hypoxia impact on atherosclerosis. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Russian Science Foundation grant

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Development of a refined ex vivo model of peritoneal adhesion formation, and a role for Connexin 43 in their development

10.21203/rs.3.rs-354162/v1 ◽

2021 ◽

Author(s):

Jia Wang Chua ◽

Leigh Madden ◽

Beng Hui Lim ◽

Anthony Phillips ◽

David Laurence Becker

Keyword(s):

Connexin 43 ◽

Drug Testing ◽

Ex Vivo ◽

Adhesion Formation ◽

Ex Vivo Model ◽

Peritoneal Adhesions ◽

Peritoneal Tissue ◽

Junction Protein ◽

The Impact

Abstract Despite many advances across the surgical sciences, post-surgical peritoneal adhesions still pose a considerable risk in modern-day procedures. We have developed a novel mouse peritoneal strip ex vivo adhesion model which may serve to bridge the gap between single cell culture systems and in vivo animal drug testing for the assessment of potential anti-adhesion agents, and study of causality of the process.We investigated the optimal conditions for adhesion formation with mouse peritoneal tissue strips by modifying an existing ex vivo rat model of peritoneal adhesions. We assessed the impact of the following conditions on the formation of adhesions: contact pressure, abrasions, and the presence of clotted blood.Macroscopic adhesions were detected in all mouse peritoneal strips exposed to specific conditions, namely abrasions and clotted blood, where peritoneal surfaces were kept in contact with pressure using cotton gauze in a tissue cassette. Adhesions were confirmed microscopically. Interestingly, Connexin 43, a gap junction protein, was found to be upregulated at sites of adhesions. Key features of this model were the use of padding the abraded tissue with gauze and the use of a standardised volume of clotted blood. Using this model, peritoneal strips cultured with clotted blood between abraded surfaces were found to reproducibly develop adhesion bands at 72 hours.

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Protective properties of grape-seed proanthocyanidins in human ex vivo acute colonic dysfunction induced by dextran sodium sulfate

European Journal of Nutrition ◽

10.1007/s00394-020-02222-3 ◽

2020 ◽

Cited By ~ 3

Author(s):

Carlos González-Quilen ◽

Carme Grau-Bové ◽

Rosa Jorba-Martín ◽

Aleidis Caro-Tarragó ◽

Montserrat Pinent ◽

...

Keyword(s):

Sodium Sulfate ◽

Ex Vivo ◽

Grape Seed ◽

Dextran Sodium Sulfate ◽

Protective Properties ◽

Grape Seed Proanthocyanidins

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Evaluation of the Prebiotic Potential of a Commercial Synbiotic Food Ingredient on Gut Microbiota in an Ex Vivo Model of the Human Colon

Nutrients ◽

10.3390/nu12092669 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2669

Author(s):

Walid Mottawea ◽

Salma Sultan ◽

Kara Landau ◽

Nicolas Bordenave ◽

Riadh Hammami

Keyword(s):

Gut Microbiota ◽

Microcrystalline Cellulose ◽

Dietary Intervention ◽

Continuous Fermentation ◽

Ex Vivo ◽

Gut Health ◽

Ex Vivo Model ◽

Food Ingredient ◽

Test Formulation ◽

The Impact

Behavior and mood disorders have been linked to gut microbiota dysbiosis through the “microbiota-gut-brain axis”. Microbiota-targeting interventions are promising therapeutic modalities to restore or even maintain normal microbiome composition and activity in these disorders. Here, we test the impact of a commercial synbiotic formulation on gut microbiota composition and metabolic activity. We employed an ex-vivo continuous fermentation model that simulates the proximal colon to assess the effect of this formulation on microbiota structure and functionality as compared to no treatment control and microcrystalline cellulose as a dietary fiber control. The test formulation did not alter the diversity of gut microbiota over 48 h of treatment. However, it induced the enrichment of Lactobacillus, Collinsella and Erysipelotrichaceae. The test formulation significantly increased the level of microbiota-generated butyrate within 12 h of treatment as compared to 24 h required by microcrystalline cellulose to boost its production. The test formulation did not lead to a significant change in amino acid profiles. These results provide evidence of potential benefits related to synbiotic effects and general gut health and support the potential of this food formulation as a therapeutic dietary intervention in mood and behavior disorders.

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