Abstract 303: CD44 Activation Protects Human Sclerotic-derived Valvular Interstitial Cells from Calcification

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Paolo Poggio ◽  
Emanuela Branchetti ◽  
Rachana Sainger ◽  
Juan Grau ◽  
Eric Lai ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Early Stage ◽  
Interstitial Cells ◽  
Calcium Deposition ◽  
Proximity Ligation Assay ◽  
Valvular Interstitial Cells ◽  
Direct Role ◽  
Aortic Sclerosis

Introduction. The activation of Valvular Interstitial Cells (VIC) towards an osteoblast-like phenotype is a cellular hallmark of pathological progression towards Aortic Stenosis (AS). In recent years several clinical trials have failed to halt or revert the progression of this prevalent disease. The ability to prevent end-stage AS requires the understanding of the molecular events associated with the early phase of valve degeneration, a condition known as Aortic Sclerosis (ASc). In the last few years the transmembrane receptor CD44 has been studied as a putative molecule for cardiovascular drug therapy. We reported that the functional interaction between CD44 and one of its ligand, Osteopontin (OPN), protects vascular smooth muscle cells from calcification. More recently, we demonstrated that sclerotic tissues show increased expression of Bone Morphogenetic Protein 4 (BMP4) and BMP4 directly stimulates osteoblast-like transdifferentiation and calcification of VICs. Therefore we hypothesized a direct role of CD44 activation in protecting human Aortic Sclerosis-derived VICs from calcification. Methods. Human VICs from Control, ASc, and AS (n=5 each group) were isolated. Histological, cellular and molecular analysis, and in situ Proximity Ligation Assay were used to investigate the role of CD44 and OPN in VIC calcification. BMP4 treatments were used to promote VIC activation. Osteoblast-like transdifferentiation was analyzed using Alkaline Phosphatase (ALP) expression. Results. CD44 and OPN, as well as their functional binding, were increased in sclerotic and stenotic tissues compared to healthy controls in vitro and ex vivo. CD44-OPN binding prevented in vitro calcification induced by inorganic phosphate on human ASc-derived VICs. A neutralizing antibody against CD44, under BMP4 treatments, promoted calcium deposition along with increased expression of OPN and ALP. Conclusion. Our results generate an important insight into the molecular mechanism of VIC calcification. We proved that CD44-OPN direct interaction inhibits calcification of Aortic Sclerosis-derived VICs, suggesting that CD44 activation could have a protective role against VIC osteoblast-like transdifferentiation and calcification in the early stage of the disease.

scholarly journals Antihuman immunoglobulin affinity immunoadsorption strongly decreases proteinuria in patients with relapsing nephrotic syndrome.

1998 ◽  
Vol 9 (9) ◽  
pp. 1709-1715
Author(s):  
J Dantal ◽  
Y Godfrin ◽  
R Koll ◽  
S Perretto ◽  
J Naulet ◽  
...  
Keyword(s):  
Nephrotic Syndrome ◽  
Ex Vivo ◽  
Protein A ◽  
Affinity Column ◽  
Focal Glomerulosclerosis ◽  
Direct Role ◽  
First Time ◽  
Firm Evidence

Approximately 20 to 30% of patients with idiopathic nephrotic syndrome and focal glomerulosclerosis experience a relapse of their nephrotic syndrome after transplantation. Previously, it has been shown that ex vivo immunoadsorption on protein A strongly (although transiently) reduces proteinuria in relapsing patients. To investigate whether the factor(s) that give rise to albuminuria are bound directly to protein A in the immunoadsorption procedure or are part of a complex with Ig, four patients with relapse of focal glomerulosclerosis presenting as nephrotic syndrome after transplantation were treated, sequentially, using a (non-protein A) anti-Ig affinity column and a protein A column. This study reports that the effect on proteinuria of immunoadsorption using an anti-Ig immunoaffinity column is comparable in its magnitude and kinetics to that of immunoadsorption on protein A. The two procedures were also equally effective in depleting the relapsing patients' plasma of a factor capable of altering the albumin permselectivity of isolated glomeruli in vitro. This study demonstrates for the first time that immunoglobulins have a role in the nephrotic syndrome. In addition, the fact that the two different immunoadsorption procedures both resulted in the removal of the same putative albuminuric factor in these patients and that no autoreactivity of eluted immunoglobulins was observed on human tissues strongly suggests that the factor or factors that may be responsible for immediate nephrotic syndrome after transplantation are bound to an immunoglobulin. However, no firm evidence can be yet provided against a direct role of immunoglobulins.

scholarly journals Direct Role of Adiponectin and Adiponectin Receptors in Endometrial Cancer: In Vitro and Ex Vivo Studies in Humans

2011 ◽  
Vol 10 (12) ◽  
pp. 2234-2243 ◽  
Author(s):  
Hyun-Seuk Moon ◽  
John P. Chamberland ◽  
Konstantinos Aronis ◽  
Sofia Tseleni-Balafouta ◽  
Christos S. Mantzoros
Keyword(s):  
Endometrial Cancer ◽  
Ex Vivo ◽  
Adiponectin Receptors ◽  
Direct Role

scholarly journals Expansion of Myeloid Derived Suppressor Cells Contributes to Platelet Activation by L-Arginine Deprivation during SARS-CoV-2 Infection

Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 2111
Author(s):  
Alessandra Sacchi ◽  
Germana Grassi ◽  
Stefania Notari ◽  
Simona Gili ◽  
Veronica Bordoni ◽  
...  
Keyword(s):  
Platelet Activation ◽  
Ex Vivo ◽  
Critical Role ◽  
Suppressor Cells ◽  
Myeloid Derived Suppressor Cells ◽  
Direct Role ◽  
Healthy Donors ◽  
Arginine Deprivation

Massive platelet activation and thrombotic events characterize severe COVID-19, highlighting their critical role in SARS-CoV-2-induced immunopathology. Since there is a well-described expansion of myeloid-derived suppressor cells (MDSC) in severe COVID-19, we evaluated their possible role in platelet activation during SARS-CoV-2 infection. During COVID-19, a lower plasmatic L-arginine level was observed compared to healthy donors, which correlated with MDSC frequency. Additionally, activated GPIIb/IIIa complex (PAC-1) expression was higher on platelets from severe COVID-19 patients compared to healthy controls and inversely correlated with L-arginine plasmatic concentration. Notably, MDSC were able to induce PAC-1 expression in vitro by reducing L-arginine concentration, indicating a direct role of PMN-MDSC in platelet activation. Accordingly, we found a positive correlation between ex vivo platelet PAC-1 expression and PMN-MDSC frequency. Overall, our data demonstrate the involvement of PMN-MDSC in triggering platelet activation during COVID-19, highlighting a novel role of MDSC in driving COVID-19 pathogenesis.

The Role of Polyphenols in the Modulation of Plasma Non-Enzymatic Antioxidant Capacity (NEAC)

2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito
Keyword(s):  
Antioxidant Capacity ◽  
Dietary Intervention ◽  
Ex Vivo ◽  
The Body ◽  
Dietary Polyphenols ◽  
Enzymatic Antioxidant ◽  
Endogenous Antioxidant

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.

scholarly journals Antagonism of Adherent Invasive E. coli LF82 With Human α-defensin 5 in the Follicle-associated Epithelium of Patients With Ileal Crohn’s Disease

2020 ◽  
Author(s):  
Lina Y Alkaissi ◽  
Martin E Winberg ◽  
Stéphanie DS Heil ◽  
Staffan Haapaniemi ◽  
Pär Myrelid ◽  
...  
Keyword(s):  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Ex Vivo ◽  
Ussing Chambers ◽  
E Coli ◽  
Follicle Associated Epithelium ◽  
Vitro Model ◽  
Set Up

Abstract Background The first visible signs of Crohn’s disease (CD) are microscopic erosions over the follicle-associated epithelium (FAE). The aim of the study was to investigate the effects of human α-defensin 5 (HD5) on adherent-invasive Escherichia coli LF82 translocation and HD5 secretion after LF82 exposure in an in vitro model of human FAE and in human FAE ex vivo. Methods An in vitro FAE-model was set up by the coculture of Raji B cells and Caco-2-cl1 cells. Ileal FAE from patients with CD and controls were mounted in Ussing chambers. The effect of HD5 on LF82 translocation was studied by LF82 exposure to the cells or tissues with or without incubation with HD5. The HD5 secretion was measured in human FAE exposed to LF82 or Salmonella typhimurium. The HD5 levels were evaluated by immunofluorescence, immunoblotting, and ELISA. Results There was an increased LF82 translocation across the FAE-model compared with Caco-2-cl1 (P < 0.05). Incubation of cell/tissues with HD5 before LF82 exposure reduced bacterial passage in both models. Human FAE showed increased LF82 translocation in CD compared with controls and attenuated passage after incubation with sublethal HD5 in both CD and controls (P < 0.05). LF82 exposure resulted in a lower HD5 secretion in CD FAE compared with controls (P < 0.05), whereas Salmonella exposure caused equal secretion on CD and controls. There were significantly lower HD5 levels in CD tissues compared with controls. Conclusions Sublethal HD5 reduces the ability of LF82 to translocate through FAE. The HD5 is secreted less in CD in response to LF82, despite a normal response to Salmonella. This further implicates the integrated role of antimicrobial factors and barrier function in CD pathogenesis.

scholarly journals Inhibition of hepatic deiodination of thyroxine is caused by selenium deficiency in rats

1987 ◽  
Vol 248 (2) ◽  
pp. 443-447 ◽  
Author(s):  
G J Beckett ◽  
S E Beddows ◽  
P C Morrice ◽  
F Nicol ◽  
J R Arthur
Keyword(s):  
Thyroid Hormones ◽  
Production Rate ◽  
Selenium Deficiency ◽  
Enzyme Complex ◽  
Measurable Effect ◽  
Direct Role ◽  
Mechanism Of Inhibition ◽  
Se Deficiency

Selenium (Se) deficiency produced up to a 14-fold decrease in hepatic tri-iodothyronine (T3) production from thyroxine (T4) in vitro. The T3 production rate could not be restored by the addition of a variety of cofactors, nor by the addition of control homogenate. The impairment in hepatic T3 production observed in Se deficiency was reflected in the concentrations of thyroid hormones circulating in plasma, T4 being increased approx. 40% and T3 being decreased by 30%. However, the fall in plasma T3 concentrations was smaller than might be expected in view of the marked decreased in T3 production. Se deficiency had no measurable effect on plasma reverse-tri-iodothyronine concentrations. The data suggest that Se deficiency produces an inhibition of both 5- and 5′-deiodination, consistent with the widely held view that these reactions are catalysed by the same enzyme complex. The mechanism of inhibition appears not be mediated by changes in thiol levels, but a direct role of Se in the activity of the deiodinase complex cannot be excluded.

scholarly journals CD133 Promotes Adhesion to the Ovarian Cancer Metastatic Niche

2018 ◽  
Vol 11 ◽  
pp. 117906441876788 ◽  
Author(s):  
Lynn Roy ◽  
Alexander Bobbs ◽  
Rachel Sattler ◽  
Jeffrey L Kurkewich ◽  
Paige B Dausinas ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cancer Metastasis ◽  
Ex Vivo ◽  
Surface Protein ◽  
Ovarian Cancer Cells ◽  
Metastatic Niche ◽  
Attractive Therapeutic Target ◽  
Peritoneal Mesothelium

Cancer stem cells (CSCs) are an attractive therapeutic target due to their predicted role in both metastasis and chemoresistance. One of the most commonly agreed on markers for ovarian CSCs is the cell surface protein CD133. CD133+ ovarian CSCs have increased tumorigenicity, resistance to chemotherapy, and increased metastasis. Therefore, we were interested in defining how CD133 is regulated and whether it has a role in tumor metastasis. Previously we found that overexpression of the transcription factor, ARID3B, increased the expression of PROM1 (CD133 gene) in ovarian cancer cells in vitro and in xenograft tumors. We report that ARID3B directly regulates PROM1 expression. Importantly, in a xenograft mouse model of ovarian cancer, knockdown of PROM1 in cells expressing exogenous ARID3B resulted in increased survival time compared with cells expressing ARID3B and a control short hairpin RNA. This indicated that ARID3B regulation of PROM1 is critical for tumor growth. Moreover, we hypothesized that CD133 may affect metastatic spread. Given that the peritoneal mesothelium is a major site of ovarian cancer metastasis, we explored the role of PROM1 in mesothelial attachment. PROM1 expression increased adhesion to mesothelium in vitro and ex vivo. Collectively, our work demonstrates that ARID3B regulates PROM1 adhesion to the ovarian cancer metastatic niche.

scholarly journals Heparan sulfate and heparin interactions with proteins

2015 ◽  
Vol 12 (110) ◽  
pp. 20150589 ◽  
Author(s):  
Maria C. Z. Meneghetti ◽  
Ashley J. Hughes ◽  
Timothy R. Rudd ◽  
Helena B. Nader ◽  
Andrew K. Powell ◽  
...  
Keyword(s):  
Heparan Sulfate ◽  
Ex Vivo ◽  
Sequence Specificity ◽  
Structure Activity ◽  
Multiple Binding Sites ◽  
Multiple Binding ◽  
Heparin Activity

Heparan sulfate (HS) polysaccharides are ubiquitous components of the cell surface and extracellular matrix of all multicellular animals, whereas heparin is present within mast cells and can be viewed as a more sulfated, tissue-specific, HS variant. HS and heparin regulate biological processes through interactions with a large repertoire of proteins. Owing to these interactions and diverse effects observed during in vitro , ex vivo and in vivo experiments, manifold biological/pharmacological activities have been attributed to them. The properties that have been thought to bestow protein binding and biological activity upon HS and heparin vary from high levels of sequence specificity to a dependence on charge. In contrast to these opposing opinions, we will argue that the evidence supports both a level of redundancy and a degree of selectivity in the structure–activity relationship. The relationship between this apparent redundancy, the multi-dentate nature of heparin and HS polysaccharide chains, their involvement in protein networks and the multiple binding sites on proteins, each possessing different properties, will also be considered. Finally, the role of cations in modulating HS/heparin activity will be reviewed and some of the implications for structure–activity relationships and regulation will be discussed.

scholarly journals The pathophysiologic role of the protein kinase Cδ pathway in the intervertebral discs of rabbits and mice: In vitro, ex vivo, and in vivo studies

2012 ◽  
Vol 64 (6) ◽  
pp. 1950-1959 ◽  
Author(s):  
Michael B. Ellman ◽  
Jae-Sung Kim ◽  
Howard S. An ◽  
Jeffrey S. Kroin ◽  
Xin Li ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Ex Vivo ◽  
Intervertebral Discs ◽  
In Vivo Studies ◽  
Protein Kinase Cδ
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