scholarly journals Effect of hepatocyte-stimulating factor and glucocorticoids on plasma fibronectin levels

1986 ◽  
Vol 238 (2) ◽  
pp. 365-371 ◽  
Author(s):  
D L Amrani ◽  
D Mauzy-Melitz ◽  
M W Mosesson
Keyword(s):  
Acute Phase Protein ◽  
Plasma Fibronectin ◽  
Phagocytic Cells ◽  
Serum Samples ◽  
Exclusion Chromatography ◽  
A Minor ◽  
Two Peaks ◽  
Stimulating Factor

We evaluated the effects of hepatocyte-stimulating factor (HSF) and a glucocorticoid (dexamethasone) on changes in the levels, in vivo and in vitro, of plasma fibronectin (Fn), a glycoprotein that is synthesized and secreted by hepatocytes. In turpentine-treated chickens, plasma levels of Fn, which peaked at 48 h (whereas fibrinogen levels were maximum at 72 h) rose 200-250% over basal levels, whereas albumin levels decreased by 20-40%. Corticosterone levels in serum samples taken between 5 and 48 h after injection revealed a 124% increase in hormone levels at 24 h in turpentine-treated chickens. We also showed that circulating HSF levels were maximal 8 to 12 h after injection and that HSF activity, as assessed by molecular-exclusion chromatography, was eluted in the 30-45 kDa range. Addition of either serum-derived HSF or dexamethasone (2 nM) to chick hepatocyte cultures resulted in a 130-150% increase in secreted Fn as well as in fibrinogen. When HSF and dexamethasone were added together, a 360-489% increase in the secreted levels of both proteins was found. Chicken mononuclear phagocytic cells treated with lipopolysaccharide secreted an HSF activity that was eluted in two peaks, a minor peak at approximately 70 kDa and a major peak in the 25-40 kDa range. Addition of mononuclear-cell-derived HSF resulted in a greater increase in Fn levels than did the addition of serum HSF. These findings indicate that Fn, like fibrinogen, is an acute-phase protein, the production of which, at least in chickens, is stimulated by HSF and glucocorticoids in an additive manner.

FRACTIONATION OF MAMMALIAN CHROMATIN

1972 ◽  
Vol 71 (2_Suppla) ◽  
pp. S112-S129 ◽  
Author(s):  
Michel Janowski ◽  
DeLill S. Nasser ◽  
Brian J. McCarthy
Keyword(s):  
Chromatin Structure ◽  
Active Fraction ◽  
E Coli ◽  
Chromatin Fraction ◽  
Exclusion Chromatography ◽  
Nascent Rna ◽  
Active Peak ◽  
Two Peaks

ABSTRACT Sheared chromatin may be separated into two peaks representing active and inactive fractions by gel exclusion chromatography on agarose columns. The active fraction is identified by the presence of nascent RNA chains synthesized in vivo or in vitro. Similarly, 3H labelled E. coli polymerase binds preferentially to the front active peak. Labelled hormones become associated with the chromatin of target tissues. Again this association occurs predominantly with the minor chromatin fraction identified as active by the above criteria. The basis for fractionation and the implications for our understanding of chromatin structure are discussed.

Factors Influencing the Entry of Dye into Neutrophil Leucocytes in the Nitroblue Tetrazolium Test

1975 ◽  
Vol 48 (3) ◽  
pp. 201-212
Author(s):  
A. W. Segal ◽  
A. J. Levi
Keyword(s):  
Acute Phase Protein ◽  
Normal Subjects ◽  
Neutrophil Function ◽  
Nitroblue Tetrazolium ◽  
Phagocytic Cells ◽  
Humoral Factors ◽  
Nbt Test ◽  
Nitroblue Tetrazolium Test

1. The Nitroblue Tetrazolium (NBT) test is a measure of the phagocytosis of particulate complexes of NBT and heparin and/or fibrinogen by neutrophil leucocytes. 2. Humoral factors in the plasma of ill patients stimulate neutrophil leucocytes of normal subjects to ingest these complexes. 3. The acute phase protein, orosomucoid and endotoxin stimulate reduction of NBT in vitro and could be responsible for some positive NBT tests in vivo. 4. The effect of factors promoting phagocytosis may be masked by an inability of neutrophil leucocytes to respond to stimulation. 5. This defective neutrophil function could result from the replacement of circulating neutrophil leucocytes by less mature, less actively phagocytic cells or by the presence of circulating immune complexes.

CHARACTERIZATION OF A NEW LCAT MUTATION CAUSING FAMILIAL LCAT DEFICIENCY (FLD) AND THE ROLE OF APOE AS A MODIFIER GENE OF THE FLD PHENOTYPE

2009 ◽  
Vol 32 (6S) ◽  
pp. 3
Author(s):  
A Baass ◽  
H Wassef ◽  
M Tremblay ◽  
L Bernier ◽  
R Dufour ◽  
...  
Keyword(s):  
Modifier Gene ◽  
Size Exclusion ◽  
Plasma Lipoproteins ◽  
Lipoprotein Profile ◽  
Exclusion Chromatography ◽  
Low Hdl ◽  
Lcat Deficiency ◽  
Apoe Genotypes

Introduction: LCAT (lecithin:cholesterol acyltransferase ) is an enzyme which plays an essential role in cholesterol esterification and reverse cholesterol transport. Familial LCAT deficiency (FLD) is a disease characterized by a defect in LCAT resulting in extremely low HDL-C, premature corneal opacities, anemia as well as proteinuria and renal failure. Method: We have identified two brothers presenting characteristics of familial LCAT deficiency. We sequenced the LCAT gene, measured the lipid profile as well as the LCAT activity in 15 members of this kindred. We also characterized the plasma lipoproteins by agarose gel electrophoresis and size exclusion chromatography and sequenced several candidate genes related to dysbetalipoproteinemia in this family. Results: We have identified the first French Canadian kindred with familial LCAT deficiency. Two brothers affected by FLD, were homozygous for a novel LCAT mutation. This c.102delG mutation occurs at the codon for His35 causing a frameshift that stops transcription at codon 61 abolishing LCAT enzymatic activity both in vivo and in vitro. It has a dramatic effect on the lipoprotein profile, with an important reduction of HDL-C in both heterozygotes (22%) and homozygotes (88%) and a significant decrease in LDL-C in heterozygotes (35%) as well as homozygotes (58%). Furthermore, the lipoprotein profile differed markedly between the two affected brothers who had different APOE genotypes. We propose that APOE could be an important modifier gene explaining heterogeneity in lipoprotein profiles observed among FLD patients. Our results suggest that a LCAT-/- genotype associated with an APOE ?2 allele could be a novel mechanism leading to dysbetalipoproteinemia.

scholarly journals Effect of Different Titanium Dental Implant Surfaces on Human Adipose Mesenchymal Stem Cell Behavior. An In Vitro Comparative Study

2021 ◽  
Vol 11 (14) ◽  
pp. 6353
Author(s):  
Vittoria D’Esposito ◽  
Josè Camilla Sammartino ◽  
Pietro Formisano ◽  
Alessia Parascandolo ◽  
Domenico Liguoro ◽  
...  
Keyword(s):  
Cell Viability ◽  
Dental Implant ◽  
In Vivo Studies ◽  
Implant Surface ◽  
Cytokines And Chemokines ◽  
Titanium Dental Implant ◽  
Adhesive Ability ◽  
Stimulating Factor

Background: The aim of this research was to evaluate the effects of three different titanium (Ti) implant surfaces on the viability and secretory functions of mesenchymal stem cells isolated from a Bichat fat pad (BFP-MSCs). Methods: Four different Ti disks were used as substrate: (I) D1: smooth Ti, as control; (II) D2: chemically etched, resembling the Kontact S surface; (III) D3: sandblasted, resembling the Kontact surface; (IV) D4: blasted/etched, resembling the Kontact N surface. BFP-MSCs were plated on Ti disks for 72 h. Cell viability, adhesion on disks and release of a panel of cytokines, chemokines and growth factor were evaluated. Results: BFP-MSCs plated in wells with Ti surface showed a viability rate (~90%) and proliferative rate comparable to cells plated without disks and to cells plated on D1 disks. D2 and D4 showed the highest adhesive ability. All the Ti surfaces did not interfere with the release of cytokines, chemokines and growth factors by BFP-MSCs. However, BFP-MSCs cultured on D4 surface released a significantly higher amount of Granulocyte Colony-Stimulating Factor (G-CSF) compared either to cells plated without disks and to cells plated on D1 and D2. Conclusions: The implant surfaces examined do not impair the BFP-MSCs cell viability and preserve their secretion of cytokines and chemokines. Further in vitro and in vivo studies are necessary to define the implant surface parameters able to assure the chemokines’ optimal release for a real improvement of dental implant osseointegration.

Identification of tyrosine 706 in the kinase insert as the major colony-stimulating factor 1 (CSF-1)-stimulated autophosphorylation site in the CSF-1 receptor in a murine macrophage cell line

1990 ◽  
Vol 10 (6) ◽  
pp. 2991-3002
Author(s):  
P van der Geer ◽  
T Hunter
Keyword(s):  
Cell Line ◽  
Murine Macrophage ◽  
Colony Stimulating Factor ◽  
Macrophage Cell Line ◽  
Macrophage Cell ◽  
Major Site ◽  
Murine Macrophage Cell Line ◽  
Stimulating Factor

The receptor for colony-stimulating factor 1 (CSF-1) is a ligand-activated protein-tyrosine kinase. It has been shown previously that the CSF-1 receptor is phosphorylated on serine in vivo and that phosphorylation on tyrosine can be induced by stimulation with CSF-1. We studied the phosphorylation of the CSF-1 receptor by using the BAC1.2F5 murine macrophage cell line, which naturally expresses CSF-1 receptors. Two-dimensional tryptic phosphopeptide mapping showed that the CSF-1 receptor is phosphorylated on several different serine residues in vivo. Stimulation with CSF-1 at 37 degrees C resulted in rapid phosphorylation on tyrosine at one major site and one or two minor sites. We identified the major site as Tyr-706. The identity of Tyr-706 was confirmed by mutagenesis. This residue is located within the kinase insert domain. There was no evidence that Tyr-973 (equivalent to Tyr-969 in the human CSF-1 receptor) was phosphorylated following CSF-1 stimulation. When cells were stimulated with CSF-1 at 4 degrees C, additional phosphotyrosine-containing phosphopeptides were detected and the level of phosphorylation of the individual phosphotyrosine-containing phosphopeptides was substantially increased. In addition, we show that CSF-1 receptors are capable of autophosphorylation at six to eight major sites in vitro.

scholarly journals Influence of ionic and non-ionic radiographic contrast media on leukocyte adhesion molecules

2003 ◽  
Vol 12 (5) ◽  
pp. 269-275 ◽  
Author(s):  
Guy L. J. Vermeiren ◽  
Roel Willems ◽  
Marc J. Claeys ◽  
Chris Vrints ◽  
Herman Slegers ◽  
...  
Keyword(s):  
Coronary Angiography ◽  
Contrast Media ◽  
Adhesion Molecules ◽  
Leukocyte Adhesion ◽  
Serum Samples ◽  
Cd11b Expression ◽  
Radiographic Contrast ◽  
Radiographic Contrast Media

Background:Many papers have focused on the importance of granulocytes in the process of reperfusion and ischemia. Most of the clinical studies measured several parameters of this process during and after coronary angiography, without taking into account the effect of the radiographic contrast media (RCM) used during this procedure.Materials and methods:We performed a randomized patient study(n=37)to evaluate the effect of ionic and non-ionic RCM on granulocyte adhesion during coronary angiography. We also evaluated the influence of the ionicity and osmolarity of the different substances on granulocyte adhesion molecules inin vitroexperiments.Results:The osmolarity of patient serum samples increased from 302±1 to 309±1 mOsm/kg(P<0.05)after infusion of RCM. The CD11b expression in the samples of the non-ionic RCM treated group increased from 221±21 MFI to 377±30 MFI(P<0.05)measured as the absolute mean fluorescence intensity (MFI), yet did not alter significantly in the ionic RCM group. In contrast, thein vitroexperiments showed a reduction of the CD11b expression from 360±70 MFI to 149±30 MFI(P<0.05)in the ionic RCM group.Conclusions:The upregulation of adhesion molecules was significantly reducedin vivowith ionic RCM, while ionic substances caused opposite effectsin vitro. This effect should be taken into account when performing leukocyte functional analysis of samples taken during angiography.

Cigarette smoking, emphysema, and damage to alpha 1-proteinase inhibitor

1994 ◽  
Vol 266 (6) ◽  
pp. L593-L611 ◽  
Author(s):  
M. D. Evans ◽  
W. A. Pryor
Keyword(s):  
Cigarette Smoke ◽  
Proteinase Inhibitor ◽  
Inflammatory Cells ◽  
Lavage Fluid ◽  
Lung Lavage ◽  
Tissue Destruction ◽  
Phagocytic Cells ◽  
Lung Fluid

The proteinase-antiproteinase theory for the pathogenesis of emphysema proposes that the connective tissue destruction associated with emphysema arises from excessive proteinase activity in the lower respiratory tract. For this reason, the relative activities of neutrophil elastase and alpha 1-proteinase inhibitor (alpha 1-PI) are considered important. Most emphysema is observed in smokers; therefore, alpha 1-PI has been studied as a target for smoke-induced damage. Damage to alpha 1-PI in lung fluid could occur by several mechanisms involving species delivered to the lung by cigarette smoke and/or stimulated inflammatory cells. Oxidative damage to alpha 1-PI has received particular attention, since both cigarette smoke and inflammatory cells are rich sources of oxidants. In this article we review almost two decades of research on mechanistic studies of damage to alpha 1-PI by cigarette smoke and phagocytic cells in vitro, studies emphasizing the importance of elastinolytic activity in the pathogenesis of emphysema in vivo and studies of human lung lavage fluid to detect defects in alpha 1-PI at the molecular and functional levels.

scholarly journals Prion Disease Blood Test Using Immunoprecipitation and Improved Quaking-Induced Conversion

mBio ◽  
2011 ◽  
Vol 2 (3) ◽  
Author(s):  
Christina D. Orrú ◽  
Jason M. Wilham ◽  
Lynne D. Raymond ◽  
Franziska Kuhn ◽  
Björn Schroeder ◽  
...  
Keyword(s):  
Real Time ◽  
Blood Test ◽  
Prion Diseases ◽  
Proteinase K ◽  
Transmissible Spongiform Encephalopathies ◽  
Serum Samples ◽  
Spongiform Encephalopathies ◽  
Jakob Disease

ABSTRACT A key challenge in managing transmissible spongiform encephalopathies (TSEs) or prion diseases in medicine, agriculture, and wildlife biology is the development of practical tests for prions that are at or below infectious levels. Of particular interest are tests capable of detecting prions in blood components such as plasma, but blood typically has extremely low prion concentrations and contains inhibitors of the most sensitive prion tests. One of the latter tests is quaking-induced conversion (QuIC), which can be as sensitive as in vivo bioassays, but much more rapid, higher throughput, and less expensive. Now we have integrated antibody 15B3-based immunoprecipitation with QuIC reactions to increase sensitivity and isolate prions from inhibitors such as those in plasma samples. Coupling of immunoprecipitation and an improved real-time QuIC reaction dramatically enhanced detection of variant Creutzfeldt-Jakob disease (vCJD) brain tissue diluted into human plasma. Dilutions of 1014-fold, containing ~2 attogram (ag) per ml of proteinase K-resistant prion protein, were readily detected, indicating ~10,000-fold greater sensitivity for vCJD brain than has previously been reported. We also discriminated between plasma and serum samples from scrapie-infected and uninfected hamsters, even in early preclinical stages. This combined assay, which we call “enhanced QuIC” (eQuIC), markedly improves prospects for routine detection of low levels of prions in tissues, fluids, or environmental samples. IMPORTANCE Transmissible spongiform encephalopathies (TSEs) are largely untreatable and are difficult to diagnose definitively prior to irreversible clinical decline or death. The transmissibility of TSEs within and between species highlights the need for practical tests for even the smallest amounts of infectivity. A few sufficiently sensitive in vitro methods have been reported, but most have major limitations that would preclude their use in routine diagnostic or screening applications. Our new assay improves the outlook for such critical applications. We focused initially on blood plasma because a practical blood test for prions would be especially valuable for TSE diagnostics and risk reduction. Variant Creutzfeldt-Jakob disease (vCJD) in particular has been transmitted between humans via blood transfusions. Enhanced real-time quaking-induced conversion (eRTQ) provides by far the most sensitive detection of vCJD to date. The 15B3 antibody binds prions of multiple species, suggesting that our assay may be useful for clinical and fundamental studies of a variety of TSEs of humans and animals.

scholarly journals Mycobacterium tuberculosis Alters the Metalloprotease Activity of the COP9 Signalosome

mBio ◽  
2014 ◽  
Vol 5 (4) ◽  
Author(s):  
Lia Danelishvili ◽  
Lmar Babrak ◽  
Sasha J. Rose ◽  
Jamie Everman ◽  
Luiz E. Bermudez
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Cop9 Signalosome ◽  
Virulence Determinants ◽  
Bacterial Survival ◽  
Phagocytic Cells ◽  
Content Type ◽  
Metalloprotease Activity ◽  
Macrophage Protein

ABSTRACT Inhibition of apoptotic death of macrophages by Mycobacterium tuberculosis represents an important mechanism of virulence that results in pathogen survival both in vitro and in vivo. To identify M. tuberculosis virulence determinants involved in the modulation of apoptosis, we previously screened a transposon bank of mutants in human macrophages, and an M. tuberculosis clone with a nonfunctional Rv3354 gene was identified as incompetent to suppress apoptosis. Here, we show that the Rv3354 gene encodes a protein kinase that is secreted within mononuclear phagocytic cells and is required for M. tuberculosis virulence. The Rv3354 effector targets the metalloprotease (JAMM) domain within subunit 5 of the COP9 signalosome (CSN5), resulting in suppression of apoptosis and in the destabilization of CSN function and regulatory cullin-RING ubiquitin E3 enzymatic activity. Our observation suggests that alteration of the metalloprotease activity of CSN by Rv3354 possibly prevents the ubiquitin-dependent proteolysis of M. tuberculosis-secreted proteins. IMPORTANCE Macrophage protein degradation is regulated by a protein complex called a signalosome. One of the signalosomes associated with activation of ubiquitin and protein labeling for degradation was found to interact with a secreted protein from M. tuberculosis, which binds to the complex and inactivates it. The interference with the ability to inactivate bacterial proteins secreted in the phagocyte cytosol may have crucial importance for bacterial survival within the phagocyte.

scholarly journals Treatment with monocyte-derived partially purified GM-CSF but not G-CSF aborts the development of transplanted chloroleukemia in rats

Blood ◽  
1988 ◽  
Vol 72 (3) ◽  
pp. 1077-1080 ◽  
Author(s):  
JJ Jimenez ◽  
AA Yunis
Keyword(s):  
Conditioned Medium ◽  
Molecular Size ◽  
Myelogenous Leukemia ◽  
Rat Lung ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
Stimulating Factor

We have previously demonstrated that cultured rat chloroleukemia cells, MIA C51, will terminally differentiate to macrophages when treated with rat lung-conditioned medium in vitro and in vivo. In the present study we fractionated rat monocyte-conditioned medium by ultrafiltration according to molecular size. The fraction with molecular weight (mol wt) 30 to 50 Kd containing partially purified granulocyte-macrophage colony-stimulating factor (GM-CSF) activity caused the differentiation of C51 cells to macrophages in vitro and in diffusion chambers in vivo. Treatment of young rats with this fraction aborted the development of chloroleukemia from transplanted C51 cells. In contrast, the fraction with mol wt 10 to 30 Kd containing virtually all the G-CSF activity exhibited no differentiation activity either in vitro or in vivo. It is concluded that in this rat myelogenous leukemia model partially purified GM-CSF but not G-CSF contains the effector molecule(s) causing terminal differentiation of C51 cells and tumor cell rejection.

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