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

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.

1986 ◽  
Vol 238 (2) ◽  
pp. 365-371 ◽  
Author(s):  
D L Amrani ◽  
D Mauzy-Melitz ◽  
M W Mosesson

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.


1991 ◽  
Vol 30 (01) ◽  
pp. 35-39 ◽  
Author(s):  
H. S. Durak ◽  
M. Kitapgi ◽  
B. E. Caner ◽  
R. Senekowitsch ◽  
M. T. Ercan

Vitamin K4 was labelled with 99mTc with an efficiency higher than 97%. The compound was stable up to 24 h at room temperature, and its biodistribution in NMRI mice indicated its in vivo stability. Blood radioactivity levels were high over a wide range. 10% of the injected activity remained in blood after 24 h. Excretion was mostly via kidneys. Only the liver and kidneys concentrated appreciable amounts of radioactivity. Testis/soft tissue ratios were 1.4 and 1.57 at 6 and 24 h, respectively. Testis/blood ratios were lower than 1. In vitro studies with mouse blood indicated that 33.9 ±9.6% of the radioactivity was associated with RBCs; it was washed out almost completely with saline. Protein binding was 28.7 ±6.3% as determined by TCA precipitation. Blood clearance of 99mTc-l<4 in normal subjects showed a slow decrease of radioactivity, reaching a plateau after 16 h at 20% of the injected activity. In scintigraphic images in men the testes could be well visualized. The right/left testis ratio was 1.08 ±0.13. Testis/soft tissue and testis/blood activity ratios were highest at 3 h. These ratios were higher than those obtained with pertechnetate at 20 min post injection.99mTc-l<4 appears to be a promising radiopharmaceutical for the scintigraphic visualization of testes.


1988 ◽  
Vol 60 (02) ◽  
pp. 205-208 ◽  
Author(s):  
Paul A Kyrle ◽  
Felix Stockenhuber ◽  
Brigitte Brenner ◽  
Heinz Gössinger ◽  
Christian Korninger ◽  
...  

SummaryThe formation of prostacyclin (PGI2) and thromboxane A2 and the release of beta-thromboglobulin (beta-TG) at the site of platelet-vessel wall interaction, i.e. in blood emerging from a standardized injury of the micro vasculature made to determine bleeding time, was studied in patients with end-stage chronic renal failure undergoing regular haemodialysis and in normal subjects. In the uraemic patients, levels of 6-keto-prostaglandin F1α (6-keto-PGF1α) were 1.3-fold to 6.3-fold higher than the corresponding values in the control subjects indicating an increased PGI2 formation in chronic uraemia. Formation of thromboxane B2 (TxB2) at the site of plug formation in vivo and during whole blood clotting in vitro was similar in the uraemic subjects and in the normals excluding a major defect in platelet prostaglandin metabolism in chronic renal failure. Significantly smaller amounts of beta-TG were found in blood obtained from the site of vascular injury as well as after in vitro blood clotting in patients with chronic renal failure indicating an impairment of the a-granule release in chronic uraemia. We therefore conclude that the haemorrhagic diathesis commonly seen in patients with chronic renal failure is - at least partially - due to an acquired defect of the platelet a-granule release and an increased generation of PGI2 in the micro vasculature.


1998 ◽  
Vol 39 (2) ◽  
pp. 201-213
Author(s):  
G. Trowald-Wigh ◽  
L. Håkansson ◽  
A. Johannisson ◽  
L.E. Edqvist

1996 ◽  
Vol 270 (3) ◽  
pp. G487-G491 ◽  
Author(s):  
A. Strocchi ◽  
G. Corazza ◽  
J. Furne ◽  
C. Fine ◽  
A. Di Sario ◽  
...  

Normal intestinal absorption of nutrients requires efficient luminal mixing to deliver solute to the brush border. Lacking such mixing, the buildup of thick unstirred layers over the mucosa markedly retards absorption of rapidly transported compounds. Using a technique based on the kinetics of maltose hydrolysis, we measured the unstirred layer thickness of the jejunum of normal subjects and patients with celiac disease, as well as that of the normal rat. The jejunum of humans and rats was perfused with varying maltose concentrations, and the apparent Michaelis constant (Km) and maximal velocity (Vmax) of maltose hydrolysis were determined from double-reciprocal plots. The true Km of intestinal maltase was determined on mucosal biopsies. Unstirred layer thickness was calculated from the in vivo Vmax and apparent Km and the in vitro Km of maltase. The average unstirred layer thickness of 11 celiac patients (170 micron) was seven times greater than that of 3 controls (25 micron). The unstirred layer of each celiac exceeded that of the controls. A variety of factors could account for the less efficient luminal stirring observed in celiacs. Although speculative, villous contractility could be an important stirring mechanism that would be absent in celiacs with villous atrophy. This speculation was supported by the finding of a relatively thick unstirred layer (mean: 106 micron) in rats, an animal that lacks villous contractility. Because any increase in unstirred layer slows transport of rapidly absorbed compounds, poor stirring appears to represent a previously unrecognized defect that could contribute to malabsorption in celiac disease and, perhaps, in other intestinal disorders.


1994 ◽  
Vol 266 (6) ◽  
pp. L593-L611 ◽  
Author(s):  
M. D. Evans ◽  
W. A. Pryor

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.


mBio ◽  
2014 ◽  
Vol 5 (4) ◽  
Author(s):  
Lia Danelishvili ◽  
Lmar Babrak ◽  
Sasha J. Rose ◽  
Jamie Everman ◽  
Luiz E. Bermudez

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.


1965 ◽  
Vol 122 (4) ◽  
pp. 651-664 ◽  
Author(s):  
Joost J. Oppenheim ◽  
Jacqueline Whang ◽  
Emil Frei

The lymphocyte proliferation in repeatedly studied mixed leukocyte cultures of peripheral white blood cells from a skin graft donor and 2 recipients was significantly increased at the time of graft rejection. This was determined from the increased proportions of mononuclear cells labeling with tritiated thymidine, increased mitotic indices, and the appearance of increased numbers of transformed lymphocytes after rejection of 1st and 2nd skin grafts. The temporarily enhanced response occurred sooner and was of shorter duration after the second than after the first graft, but was quantitatively similar each time. The cell proliferation in the mixed leukocyte cultures of the two recipients was similarly affected by the homograft rejections. The cultures containing three cell populations usually manifested a greater lymphocyte response than corresponding cultures of leukocytes from only two unrelated subjects. An increase in the ratio of female recipient to male graft donor metaphases in the cultures at the time of enhanced lymphocyte transformation indicated that proliferation of the graft recipient lymphocytes was responsible for the above findings. Unmixed, unstimulated control cultures grown in autologous, the other subjects plasma, or heterologous calf serum failed to support significant lymphocyte transformation. The role of humoral factors and relationship of the in vitro cellular responses to the in vivo homograft reaction are discussed.


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