scholarly journals In vitro effects of PCDDs/Fs on NK-like cell activity of Eisenia andrei earthworms

2012 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
Hayet Belmeskine ◽  
Sami Haddad ◽  
Louise Vandelac ◽  
Michel Fournier
Keyword(s):  
Flow Cytometry ◽  
Immune Function ◽  
Cell Activity ◽  
Eisenia Andrei ◽  
Significant Stimulation ◽  
In Vitro Effects ◽  
Tumoral Cells ◽  
Stimulation Of

In this study, we assessed<em> in vitro</em> the effects of PCDD/Fs on the NK-like cell activity in<em> Eisenia andrei</em> earthworms using flow cytometry for analysis. NK-like coelomocytes isolated from <em>E. andrei</em> and used as effectors were exposed to various concentrations of PCDDs/Fs mixture, C1 (6.25x10-3 ng 2378- TCDD/mL), C2 (12.5x10-3 ng 2378-TCDD/mL) and C3 (25x10-3 ng 2378-TCDD/mL), before adding them to human tumoral cells (K562) used as targets. We evaluated the percentage of targets lysed by Nk-like cells. The results showed a significant stimulation of the NKlike activity at C3 when PCDD/Fs were not removed from effectors before contact with targets, while no effects were noted when the effectors were washed (PCDD/Fs removed) or fixed. Assessment of the viability of the targets (K562), exposed alone and separately from effectors, to the three concentrations of PCDD/Fs, C1, C2 and C3, showed that all these concentrations were cytotoxic for K562. Results suggest that PCDD/Fs concentrations tested in this assay may be considered too low to induce suppressive effects on the immune function such as the NK-like activity in <em>E. andrei</em> earthworms.

scholarly journals Contamination of erythropoietin by endotoxin: in vivo and in vitro effects on murine erythropoiesis

Blood ◽  
1979 ◽  
Vol 54 (1) ◽  
pp. 146-158 ◽  
Author(s):  
KS Zuckerman ◽  
PJ Quesenberry ◽  
J Levin ◽  
R Sullivan
Keyword(s):  
Significant Inhibition ◽  
Erythropoietic Activity ◽  
Limulus Amebocyte Lysate ◽  
Endogenous Erythropoietin ◽  
Significant Change ◽  
In Vitro Effects ◽  
Stimulation Of

Abstract Endotoxin was detected in all erythropoietin preparations tested and was removed from four lots, without loss of erythropoietic activity, by adsorption with limulus amebocyte lysate. Comparison of adsorbed (endotoxin-depleted) and nonadsorbed (endotoxin-containing) erythropoietin preparations demonstrated significant inhibition of CFU- e and BFU-e in vitro by nonadsorbed erythropoietin at concentrations higher than 0.25 U/ml and 2.0 U/ml, respectively. CFU-e and BFU-e were inhibited significantly by readdition in vitro of 10(-5)-10(-3) mug of endotoxin per unit of limulus-adsorbed erythropoietin. Administration of saline or 6 U of nonadsorbed or adsorbed erythropoietin twice a day for 4 days of CF1 mice resulted in reticulocyte counts of 2.1%, 9.9%, and 15.9%, respectively. Nonadsorbed erythropoietin resulted in a 29% decrease in erythropoiesis, a 42% decrease in CFU-e, and a 16% increase in granulopoiesis in the marrow, whereas adsorbed erythropoietin caused a 28% increase in erythropoiesis, no significant change in CFU-e and a 19% decrease in granulopoiesis in the marrow. Both preparations resulted in marked increases in splenic erythropoiesis and granulopoiesis. The effects of adsorbed erythropoietin are similar to those produced following stimulation of hematopoiesis by endogenous erythropoietin. Hemopoietic changes induced by nonadsorbed erythropoietin in vivo and in vitro are affected substantially by contamination of the erythropoietin preparations with endotoxin.

scholarly journals Effects of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans on phagocytic response of Eisenia andrei coelomocytes

2011 ◽  
Vol 1 (1) ◽  
pp. 6 ◽  
Author(s):  
Hayet Belmeskine ◽  
Pauline Brousseau ◽  
Sami Haddad ◽  
Louise Vandelac ◽  
Michel Fournier
Keyword(s):  
Flow Cytometry ◽  
Phagocytic Activity ◽  
Cytotoxic Effect ◽  
Polychlorinated Dibenzofurans ◽  
Eisenia Andrei ◽  
Phagocytic Capacity ◽  
Excessive Secretion ◽  
Phagocytic Response

The immunotoxicological effects of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDDs/Fs) mixtures on <em>Eisenia andrei </em>earthworms have never been studied. In this work we investigated these effects both for <em>in vitro </em>and <em>in vivo</em> exposure, using the viability and the phagocytic activity of coelomocytes as immunological biomarkers and the flow cytometry was used for analysis. The <em>in vitro </em>exposure revealed a cytotoxic effect of PCDD/Fs mixture (C2) containing 50&yen;10-3 ng/mL of 2, 3, 7, 8-TCDD and an induction of the phagocytic capacity at the mixture (C1) containing 25&yen;10-3 ng/mL of 2, 3, 7, 8-TCDD. In the <em>in vivo </em>filter paper exposure, the immunocompetence of earthworms was assessed after 3 h-exposure to mixtures of PCDD/Fs at the levels of C1, C2, C3 and C4 containing about; 0.05, 0.3, 0.5 and 0.83 ng of 2, 3, 7, 8-TCDD/cm&sup2;, respectively. Morphological observations showed an excessive secretion of mucus and body surface lesions in worms exposed to higher concentrations (C3 and C4), which revealed that these organisms were affected by PCDD/Fs either through skin and/or by feeding. The levels of the extruded cell yield decreased significantly at all the concentrations tested. However, the cell viability was shown to be unaffected by PCDD/Fs concentrations. It was also shown, that exposure to the highest PCDD/Fs concentrations; C2, C3 and C4 inhibited both phagocytic activity and efficiency.

scholarly journals The Role of Monocytes/Macrophages In The Pathogenesis of Immune Associated Diffuse Alveolar Hemorrhage

2021 ◽  
Author(s):  
Qing Wei ◽  
Xun Chen ◽  
Jing Liu ◽  
Yan Li ◽  
Guangmin Nong
Keyword(s):  
Flow Cytometry ◽  
Critical Role ◽  
Lavage Fluid ◽  
Peripheral Blood Monocyte ◽  
Healthy Children ◽  
Group 3 ◽  
Group 2 ◽  
Stimulation Of

Abstract Backgroud The studies in the immnue associated diffuse alveolar hemorrahge (DAH) animal models showed that monocytes/macrophages played an critical role in the pathogenesis.Whether monocytes/macrophages contribute to the pathogenesis of immune associated DAH in human is still unknow. The aim of this study was to explore the role of monocytes/macrophages in the pathogenesis of immune associated DAH in human.Methods This study was conducted in two parts. In the first part, 37 children with immune associated DAH were included (DAH group), and 18 healthy children were recruited as the controls (HC group). Peripheral blood monocyte subtype was analyzed using flow cytometry. In the second part, 24 children with immune associated DAH were included (DAH group), and 13 children with acute airway foreingn body or mild benign airway stenosis were included as the controls (HC group). Bronochoalveolar lavage fluid (BALF) was collected using bronchoscope. Cytokines in the BALF supernatant were detected using cytometric bread array. BALF supertanant was used to stimulated the macrophages in vitro. The mRNA relative expressions of IL-1β, TNFα, IL-6, TGM2, CD163 and MRC1 were detected using quantitative real-time PCR, and the expressions of CD14, CD80, CD86, CD163 and CD206 were detected using flow cytometry. Results 1. The percentage of classical monocyte was significantly increased, whereas the percentages of intermediate and non-classical monocyte were significantly decreased in the DAH group, when compared to those in the HC group. 2. The levels of MCP-1, IL-6 and IL-8 were all significantly higher in the BALF supernatant from the DAH group, when compared to those form the HC group. 3. The mRNA relative expressions of IL-1β and IL-6 as well as the expression of CD86 were significantly higher, whereas the mRNA relative expression of MRC1 as well as the expressions of CD163 and CD206 were significantly lower under the stimulation of BALF supernatant from the DAH group, when compared to that from the HC group. Conclusions Monocytes/macrophages might participate in the pathogenesis of immune associated DAH in human by enhanced M1 polarization.

scholarly journals Effect of Fluoride on Endocytosis and Surface Marker Expression Levels of Mouse B Cells In Vitro

2016 ◽  
Vol 39 (2) ◽  
pp. 596-603 ◽  
Author(s):  
Haili Ma ◽  
Zeyu Shi ◽  
Yaoze Dong ◽  
Rui Liang ◽  
Jianshan Chen ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
B Cells ◽  
Immune Function ◽  
Sodium Fluoride ◽  
Surface Marker ◽  
Expression Levels ◽  
Surface Marker Expression ◽  
Marker Expression ◽  
High Concentrations

Background/Aims: To clarify the effect of fluoride on splenic B cells, the endocytosis and surface marker expression levels of mouse splenic B cells were detected in vitro by flow cytometry. Methods: Cells were stimulated with 10 µg/mL lipopolysaccharide (LPS) and varying concentrations of Sodium Fluoride (NaF) (0, 50 µM, 100 µM, 500 µM, 1000 µM). Results: The results demonstrated that the endocytic capacity of B cells was enhanced by NaF at 50µM. NaF significantly enhanced CD80 expression at 50 µM and decreased CD86 expression at 500 µM. CD40 and CD138 expression on B cells were down-regulated at varying high concentrations of NaF. Conclusion: our results showed that the endocytic capacity, expression levels of CD40 and CD80 of B cells changed significantly at lower concentrations, whereas expression levels of CD138 and CD86 changed significantly at higher concentrations, suggesting that fluoride could inhibit immune function in animals.

Stimulation of Plasmin Activity by Aspirin

1991 ◽  
Vol 65 (04) ◽  
pp. 389-393 ◽  
Author(s):  
Ariel Milwidsky ◽  
Zvendana Finci-Yeheskel ◽  
Michael Mayer
Keyword(s):  
Binding Sites ◽  
Plasminogen Activators ◽  
Tissue Type ◽  
Amidolytic Activity ◽  
Antithrombotic Effect ◽  
Plasmin Activity ◽  
Human Control ◽  
Significant Stimulation ◽  
Stimulation Of

SummaryThis study demonstrates an enhancing effect of aspirin on the amidolytic activity of plasmin. The stimulation of plasmin by aspirin was concentration-dependent and was attained at aspirin concentrations above 2 × 10−4 M. Aspirin produced a small, reproducible and statistically significant stimulation of the chromogenic activity of plasmin upon H-D-Valyl-L-Leucyl-L-Lysine-p-nitroanilide (3-2251) or pyro-Glu-Gly-Arg-p-nitroanilide (S-2444). Kinetic analysis demonstrated a slight decrease in the affinity of plasmin for substrate 3-2251 in the presence of aspirin, reflected by a change of the Km from 3.2 × 10-4 M to 3.8 × 10-4 M, and an increase of the Vm. The reciprocal Lineweaver-Burk curve indicated an uncompetitive type of stimulation. The stimulatory effect of aspirin was abolished by the lysine analogue α-aminohexanoic acid (AHA) but not by the α-amino acid glutamic acid. The effect of AHA suggests a specific involvement of lysine binding sites (LBS) on plasmin in the interaction of the enzyme with aspirin. Tlansient acidification of plasmin abolished its response to aspirin, to AHA and to their combination. The addition of aspirin to diluted human control or pregnancy plasma in vitro stimulated the plasma-mediated cleavage of the chromogenic substrate3-2251. In contrast to its effect on plasmin, aspirin failed to change the activity of tissue-type or urokinasetype plasminogen activators. It is conceivable that in addition to the antithrombotic effect of aspirin ascribed to its interaction with the platelets, aspirin also directly stimulates plasmin activity.

Gastric and duodenal HCO3- transport in vitro: effects of hormones and local transmitters

1982 ◽  
Vol 242 (2) ◽  
pp. G100-G110 ◽  
Author(s):  
G. Flemstrom ◽  
J. R. Heylings ◽  
A. Garner
Keyword(s):  
Phosphodiesterase Inhibitor ◽  
Duodenal Mucosa ◽  
Dibutyryl Camp ◽  
Inhibitory Peptide ◽  
Luminal Membrane ◽  
Wide Range ◽  
In Vitro Effects ◽  
Histamine H2 Antagonists ◽  
Stimulation Of

Luminal application of acid was recently shown to stimulate surface epithelial HCO3(-) transport in stomach and duodenum. Effects of some potential transmitters of this response were therefore studied in amphibian gastric fundic and proximal duodenal mucosa in vitro. Duodenal HCO3- transport, which could be titrated directly, was stimulated by dibutyryl cAMP (DBcAMP, 10(-6) M), the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (10(-6) M), noradrenaline (10(-6) M), pancreatic glucagon (10(-8) M), and gastric inhibitory peptide (GIP, 10(-10) M). Stimulation by glucagon, but not by prostaglandin E2 (PGE2, 10(-6) M), required Cl- in the luminal solution and was prevented by furosemide (10(-3) M). This suggests that glucagon may affect HCO3(-)-Cl- exchange at the luminal membrane while transport stimulated by prostaglandins may be electrogenic. Stimulatory effects of glucagon and PGE2 were also additive. Gastric HCO3- transport, studied in tissues after inhibition of H+ secretion by histamine H2-antagonists, clearly differed from duodenum in that noradrenaline and GIP were inhibitory and DBcAMP was without effect. Stimulation of gastric HCO3- transport was observed with glucagon (10(-8) M), natural cholecystokinin (CCK, 10(-8) M), and CCK octapeptide (10(-7) M), CCK preparations had no effect in the duodenum. Although tested over a wide range of concentrations, no effect on either duodenal or gastric HCO3- transport was observed with histamine, pentagastrin, tetragastrin, urogastrone, ACTH, bombesin, motilin, secretin, serotonin, somatostatin, substance P, or vasoactive intestinal peptide.

Lipoate effect on carbohydrate and lipid metabolism and gastric H+ secretion

1975 ◽  
Vol 228 (3) ◽  
pp. 964-971 ◽  
Author(s):  
JB Harris ◽  
D Alonso ◽  
OH Park ◽  
D Cornfield ◽  
J Chacin
Keyword(s):  
Fatty Acids ◽  
Secretory Process ◽  
Rapid Decline ◽  
Beta Oxidation ◽  
Histamine Stimulation ◽  
Carbohydrate And Lipid Metabolism ◽  
Significant Stimulation ◽  
Rate Of Decline ◽  
Stimulation Of

Acid secretion (QH+) and oxygen consumption (Qo2) by frog gastric mucosae in vitro were sharply stimulated by lipoate. A rapid decline followed stimulation, subsequently falling below control values. Addition of only glucose or lactate had no effect on Qo2 or QH+. Pyruvate caused slight significant stimulation of Qo2. Any one of these compounds added to lipoate-treated mucosae increased the stimulatory effect of lipoate and markedly slowed the rate of decline subsequent to maximum stimulation. Various fatty acids had a moderate-to-high stimulatory effect on Qo2 and QH+. Lipoate added prior to the addition of fatty acids decreased the stimulatory effect of buryrate (minus 56%), decanoate (minus 87%), and palmitate (minus 60%). Propionate became an inhibitor in the presence of lipoate. Lipoate increased (plus 100%) the amount of glycogen oxidized and decreased (minus 69%) the amount of triglycerides oxidized. Lipoate-treated mucosae did not respond to histamine. Addition of glucose restored responsiveness. The results indicate that beta-oxidation of fatty acids plays a major role in the acid secretory process and is centrally involved in cyclic AMP and histamine stimulation of QH+.

scholarly journals cAMP-dependent inhibition is dominant in regulating superoxide production in the bone-resorbing osteoclasts

1998 ◽  
Vol 158 (3) ◽  
pp. 311-318 ◽  
Author(s):  
CE Berger ◽  
BR Horrocks ◽  
HK Datta
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Pertussis Toxin ◽  
Kinase C ◽  
Significant Stimulation ◽  
Dependent Inhibition ◽  
Dependent Protein ◽  
O2 Production ◽  
Stimulation Of

Calciotropic hormones such as parathyroid hormone (PTH) and calcitonin have been shown to have stimulatory and inhibitory effects respectively on superoxide anion (O2-) generation by osteoclasts, but the exact intracellular signalling mediating these pathways has not been investigated. In order to elucidate the intracellular pathways controlling O2- generation, we have carried out a systematic study of the effect of different agents on O2- production in osteoclasts cultured on bovine cortical bone. Dibutyryl cAMP and cholera toxin, while having no effect on the basal level of O2- production in bone-resorbing osteoclasts, were, however, found to completely block the stimulation of free radical production by PTH, pertussis toxin and ionomycin. The stimulation of O2- production was found to be independent of protein kinase C-dependent pathways since the presence of bisindolylmaleimide (GF109203X) (1 microM) did not block stimulation by PTH and pertussis toxin. Interestingly, while exposure to bisindolylmaleimide at this concentration did not have any effect on the basal level of O2- production, exposure to a higher concentration (10 microM), which is known to inhibit both protein kinase C and A, produced significant stimulation. These in vitro findings suggest that in the bone-resorbing cells, cAMP-dependent protein kinases prevent further stimulation of NADPH oxidase by agents such as PTH and pertussis toxin. The increase in cAMP has also been recently demonstrated to be associated with down-regulation of the oxidative burst in adherent neutrophils; and the findings reported here suggest a similar role for cAMP in O2- generation in osteoclasts cultured on bone.

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