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Biomedical subjects

G Marone

Publications and source records attributed to G Marone.

At least 127 records · Page 7Linked to original sources
PubMed1989

Human basophil/mast cell releasability. V. Functional comparisons of cells obtained from peripheral blood, lung parenchyma, and bronchoalveolar lavage in asthmatics.

Releasability of human basophils and mast cells is an important parameter in allergic disorders. We compared IgE- and non-IgE-mediated releasability of human peripheral blood basophils with that of mast cells obtained from lung parenchyma (isolated by mechanical or enzymatic dissociation) and from bronchoalveolar lavage of normal and asthmatic donors. In a first study, the response to anti-IgE, Staph A, Con A, f-met peptide, and Ca2+ ionophore A23187 of basophils obtained from 52 donors was compared with that of mast cells isolated enzymatically (PMCE) or mechanically (PMCM) from lung parenchyma obtained during surgery. The histamine content of basophils (1.1 +/- 0.1 pg/cell) was significantly lower than that of PMCE (4.1 +/- 0.3 pg/cell; p less than 0.001) and PMCM (3.7 +/- 0.3; p less than 0.001). The maximal percent anti-IgE-induced histamine secretion in basophils (41.3 +/- 3.6) was higher than in PMCE (17.5 +/- 1.8) and in PMCM (13.8 +/- 1.5). Similarly, the response to Staph A and Con A was higher in basophils (29 +/- 3.9 and 31.6 +/- 4.9, respectively) than in PMCE (3.5 +/- 0.6 and 3.3 +/- 0.8, respectively) and PMCM (5.1 +/- 1.3 and 8.8 +/- 2.2, respectively). A positive correlation between the maximal percent of histamine release induced by anti-IgE and Staph A was found in basophils (rs = 0.61; p less than 0.001), whereas there was a negative correlation between the reactivity of PMCE (rs = 0.67; p less than 0.001) and PMCM (rs = -0.40; p less than 0.001) to anti-IgE and their reactivity to Staph A.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

The role of mast cell and basophil activation in human allergic reactions.

Recently developed techniques of purification of human basophils and mast cells from different anatomical sites have made possible the investigation of the biochemical steps leading to mediator release and the pharmacological control of cells participating in allergic reactions. These techniques have also outlined differences between mast cells and basophils with regard to mediator release, activity of secretagogues and pharmacological modulation. The similarities and analogies between in vivo observations and in vitro findings with human mast cells and basophils suggest that the in vitro findings may represent important models for obtaining insight into the mechanisms and to develop therapeutic agents for the treatment of allergic diseases.

Animals↗
PubMed1988

Adenosine potentiates mediator release from human lung mast cells.

Micromolar concentrations of adenosine were found to potentiate the release of histamine and leukotriene C4 (LTC4) from immunologically activated human lung mast cells (HLMC). Structurally modified congeners of adenosine including 5'-N-ethylcarboxamideadenosine (NECA) and R-phenylisopropyladenosine (R-PIA) also potentiated mediator release. A rank order of potency was established where NECA greater than R-PIA for the potentiation of both LTC4 production and histamine secretion. Mast cells isolated by either enzymatic or mechanical means from human lung parenchyma were both similarly responsive to the modulatory effects of adenosine and analogues, and the potency series of NECA greater than R-PIA also applied. Moreover, histamine release induced by the calcium ionophore A23187 was augmented by NECA, R-PIA, and adenosine and in that potency order. Dipyridamole, an agent thought to impede the intracellular uptake of adenosine, failed to reverse the nucleoside's enhancement of IgE-mediated secretion. The irreversible inhibitor of adenosine deaminase, deoxycoformycin, did not modify the adenosine enhancement of stimulated secretion. Low concentrations of methylxanthines, which antagonize responses mediated at cell surface adenosine receptors, were inconsistent in their effects. Theophylline modestly reversed the adenosine-induced potentiation of IgE-mediated LTC4 generation but not histamine release. Studies employing 8-phenyltheophylline were complicated by the methylxanthine possessing inhibitory properties of its own at concentrations expected to antagonize a nucleoside-mediated effect. In total, these results suggest that the response of HLMC to adenosine describes properties most consistent with an A2/Ra-like process, although an interaction via an, as yet, uncharacterized cell surface receptor cannot be excluded.

Adenosine↗
PubMed1987

Inhibition of IgE-mediated release of histamine and peptide leukotriene from human basophils and mast cells by forskolin.

Forskolin, a diterpene compound isolated from the roots of Coleus forskohlii, activates adenylate cyclase in membranes from a variety of mammalian tissues. We found that forskolin (10(-7) to 3 X 10(-5) M) caused a concentration-related inhibition of IgE-mediated release of histamine and peptide leukotriene C4 (LTC4) from human basophils and lung mast cells. There was a significant linear correlation between the per cent inhibition of histamine and LTC4 release from both cell types. However, in both systems forskolin exerted a significantly greater inhibitory effect on LTC4 release than on histamine release. The concentration-response inhibition curve was paralleled by a forskolin-induced rise in cAMP levels in human leukocyte and mast cell preparations. The relationship between the effect of forskolin and the cAMP concentration was supported by the finding that forskolin inhibited the "first stage" of antigen-induced histamine release, but not the release caused by the Ca2+ ionophore, A23187. Propranolol, a competitive beta-receptor antagonist, did not block the inhibition of mediator release or the cAMP accumulation caused by forskolin. These data suggest that forskolin modulates the release of mediators of immediate hypersensitivity reactions via the activation of adenylate cyclase in human basophils and mast cells.

Adenylyl Cyclases↗
PubMed1987

Functional heterogeneity of human mast cells from different anatomic sites: in vitro responses to morphine sulfate.

The responses of human cutaneous, pulmonary, intestinal, and cardiac tissue mast cells to the histamine-releasing agent morphine sulfate (MS) were investigated in vitro. Human cutaneous mast cells released significant amounts of histamine in the presence of 1 to 100 mumol/L concentrations of MS. Histamine release was detectable within 5 minutes after challenge and was complete by 15 minutes. A maximal histamine release of 21.6% (+/- 1.4 SEM) was observed after stimulation with 100 mumol/L of MS. This MS effect was inhibited by the opiate receptor antagonist naloxone with a 59% inhibition detected at equimolar concentrations and an 88% inhibition occurring in the presence of a tenfold molar excess of naloxone. Naloxone did not alter the cutaneous mast cell response to the calcium ionophore A23187. Human mast cells derived from pulmonary, intestinal, and cardiac tissues, as well as blood basophils, did not release histamine after stimulation with 1 to 200 mumol/L of MS, whereas each of these cell preparations responded to an IgE-mediated stimulus. The results of this study demonstrate that cutaneous mast cells release inflammatory mediators after stimulation by MS, whereas mast cells residing in lung, heart, and gastrointestinal tissues do not. These observations indicate that human mast cells in different anatomic sites can vary in their functional responses.

Basophils↗
PubMed1987

Effects of histamine on coronary hemodynamics in humans: role of H1 and H2 receptors.

To evaluate whether histamine exerts a direct effect on coronary hemodynamics in humans, and to investigate the role played by H1 and H2 receptors in this response, intracoronary saline solution or histamine (4 micrograms) was administered in 10 patients with normal coronary arteries during diagnostic cardiac catheterization. Histamine injection was repeated after intravenous cimetidine (400 mg) and diphenhydramine (10 mg). The electrocardiogram, arterial pressure and thermodilution coronary blood flow were continuously monitored during and for 40 seconds after each injection. Immediately after histamine injection there was a significant increase in coronary blood flow (65 +/- 6%) and a decrease in coronary vascular resistance (-40 +/- 3%) (both p less than 0.001), with minor changes in the RR interval and the mean arterial pressure. H2 receptor blockade with cimetidine did not affect these changes, while H1 receptor blockade with diphenhydramine significantly reduced the histamine-induced increase in coronary blood flow and the decrease in coronary vascular resistance (26 +/- 6%, p less than 0.005 and -18 +/- 5%, p less than 0.001, respectively). Twenty to 30 seconds after histamine injection, a significant decrease in mean arterial pressure (-17 +/- 2%, p less than 0.001) and in the RR interval (-4 +/- 1%, p less than 0.01) was observed. These changes persisted after H2 receptor blockade with cimetidine, but were completely abolished after H1 receptor blockade with diphenhydramine. In each case coronary and systemic hemodynamics returned to normal within 40 seconds of the injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Mechanism of activation of human basophils by Staphylococcus aureus Cowan 1.

We investigated the capacity of Staphylococcus aureus Cowan 1 and S. aureus Wood 46 to induce histamine release from human basophils in vitro. S. aureus Cowan 1 (10(5) to 10(7)/ml), which synthesizes protein A (Staph A), stimulated the release of histamine from basophils, whereas S. aureus Wood 46 (10(5) to 2 X 10(7)/ml), which does not synthesize Staph A, did not induce histamine secretion. Soluble Staph A (10(-3) to 10 micrograms/ml), but not staphylococcal enterotoxin A, induced histamine secretion from human basophils. Staph A binds through its classical site to the Fc region of human immunoglobulin G (IgG) and through its alternative site to the Fab portion of the different human immunoglobulins. Hyperiodination of Staph A, which destroys over 90% of the original Fc reactivity without altering the Fab-binding site, did not alter the ability of the protein to induce histamine release. The stimulating effect of Staph A was dose dependently inhibited by preincubation with human polyclonal IgG (0.3 to 100 micrograms/ml) and a human monoclonal IgM (0.3 to 100 micrograms/ml) which have F(ab')-Staph A reactivity. In contrast, rabbit IgG, which possesses only Fc-Staph A reactivity, and a Staph A-unreactive human monoclonal IgM did not inhibit Staph A activity. Similar results were obtained with intact S. aureus Cowan 1. Preincubation with either Staph A or anti-IgE (rabbit anti-Fc epsilon) resulted in complete desensitization to a subsequent challenge with the homologous stimulus. Staph A and anti-IgE induced partial cross-densensitization to the heterologous stimulus. Cells preincubated with anti-IgG (rabbit anti-Fc gamma) lost a small but significant part of their ability to release with Staph A but did not lose their response to anti-IgE. Basophils from which IgE had been dissociated by brief exposure to lactic acid no longer released histamine in response to anti-IgE and Staph A. When basophils from which IgE had been dissociated were incubated with human polyclonal IgE, they regained their ability to induce histamine in response to Staph A and anti-IgE. In contrast, two monoclonal IgEs which do not bind to Staph A did not restore the basophil responsiveness to Staph A. Furthermore, there was complete cross-desensitization between soluble Staph A and S. aureus Cowan 1, while cells desensitized to S. aureus Wood 46 released normally with Staph A and S. aureus Cowan 1.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1987

Betamethasone modulates the biological function of human polymorphonuclear leukocytes.

We have examined the influence of betamethasone (BT) on cyclic AMP (cAMP) metabolism and lysosomal enzyme release from highly purified (approximately equal to 99%) human polymorphonuclear leukocytes (PMNs). Preincubation (1-24 h) of human PMNs with BT (10(-9)-10(-5) M) had no effect on either cAMP content or on beta-glucuronidase release induced by formyl-containing tripeptide (f-met peptide). Preincubation (16-24 h) of PMNs with BT (10(-8)-10(-7) M) dose-dependently potentiated the cAMP accumulation caused by beta-agonists (isoproterenol), adenosine A2/Ra agonist (NECA), prostaglandin E1 (PGE1) and histamine in PMNs. Similarly, BT potentiated the inhibition of f-met peptide-induced beta-glucuronidase release from human PMNs caused by PGE1 (10(-6) M), histamine (2 X 10(-5) M), NECA (10(-4) M) and isoproterenol (10(-6) M).

Adenylyl Cyclases↗
PubMed1987

Inhibition of ischemia-induced phospholipase activation by quinacrine protects jeopardized myocardium in rats with coronary artery occlusion.

Phospholipase activation has been proposed as one relevant biochemical step toward irreversible myocardial injury during ischemia. Accordingly, after coronary artery occlusion, the time course of myocardial phospholipid degradation was studied in 83 control rats and 84 rats treated with quinacrine (75 mg/kg s.c. every 8 hr), a phospholipase inhibitor. Animals were sacrificed at different times ranging from 2 to 48 hr postocclusion. In controls a rapid fall in left ventricular phospholipid concentration (from 1.33 +/- 0.12 to 0.67 +/- 0.05 micrograms of P/mg of protein) and creatinkinase (CK) activity (from 9.84 +/- 0.49 to 6.93 +/- 0.60 I.U./mg of protein) was observed within 4 hr postocclusion. In quinacrine-treated animals phospholipids and CK also fell initially; however, 24 and 48 hr after occlusion they were higher than in controls (phospholipids: 0.99 +/- 0.05 vs. 0.62 +/- 0.04 micrograms of P/mg of protein, P less than .001; CK: 7.76 +/- 0.54 vs. 4.99 +/- 0.37 I.U./mg of protein, P less than .001, at 48 hr). Additional rats surviving coronary occlusion were divided randomly into a control (n = 14) and three treated groups receiving quinacrine every 8 hr at the dose of 5 (n = 13), 20 (n = 13) or 75 mg/kg (n = 15); 13 rats were sham-operated. Forty-eight hours postocclusion myocardial phospholipids were measured and infarct size calculated by CK depletion. Infarct size was significantly smaller in high dose quinacrine-treated than in control rats (16.6 +/- 5.7 vs. 42.1 +/- 4.4% of left ventricle, P less than .001). In treated animals, myocardial phospholipid concentration was also significantly higher.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Human basophil releasability. III. Genetic control of human basophil releasability.

Basophil releasability implies that, in addition to the surface density of IgE molecules, biochemical events determine the capacity to release chemical mediators in response to activating stimuli. We studied the IgE (anti-IgE)-mediated and non-IgE-mediated (f-met peptide and the Ca2+ ionophore A23187) releasability of human basophils obtained from 14 monozygotic (MZ) (ages 25.7 +/- 13.3 yr; mean +/- SDM) and 13 dizygotic (DZ) twin pairs (ages 20.4 +/- 9.9 yr). A significant intrapair correlation coefficient of the maximal percent of anti-IgE-induced histamine release was found in the MZ, whereas no significant correlation was found in the DZ. The mean intrapair variance of anti-IgE-induced histamine release in MZ (VMZ) and in DZ (VDZ) gave an F value equal to 3.84 (p less than 0.01) and a heritability (H) index of 0.74. Similar findings were obtained with respect to the sensitivity to a standard concentration (10(-1) micrograms/ml) of anti-IgE. No correlation between serum IgE level and anti-IgE-induced histamine release was found in either MZ or DZ. A significant intrapair correlation coefficient of f-met peptide-induced histamine release was found in both the MZ and the DZ. The difference between MZ and DZ was not significant. The VMZ and the VDZ of the f-met peptide-induced histamine release gave an F value of 1.52 (NS) and an H value of 0.34. The intrapair correlation coefficient of A23187-induced release was significant in MZ and not significant in DZ. The mean intrapair variance of A23187-induced histamine release gave an F value of 2.33 (NS) and an H index of 0.57. Similar findings were obtained by using suboptimal (3 X 10(-1) micrograms/ml) concentrations of A23187. There was no correlation between the sensitivity of basophils to release in response to anti-IgE and their response to f-met peptide or A23187, in either the MZ or the DZ. We conclude that the ability of basophils to respond to anti-IgE and A23187 is influenced by genetic factors.

Antibodies, Anti-Idiotypic↗
PubMed1986

Possible role of calmodulin in the control of histamine release from human basophil leukocytes.

We investigated the possible role of calmodulin (CaM) in the control of histamine release from human basophil leukocytes using several CaM antagonists. Trifluoperazine (TFP) (10(-6)-2 X 10(-5) M), pimozide (10(-6)-1.5 X 10(-5) M), chlorpromazine (CPZ) (10(-5)-10(-4) M) and promethazine (PMZ) (2 X 10(-5)-10(-4) M) inhibited in vitro histamine secretion from human basophils induced by several immunological (antigen, anti-IgE, and formyl-L-methionyl-L-leucyl-L-phenylalanine: f-met peptide) and nonimmunological (Ca2+ ionophore A23187 and the tumor promoter 12-0-tetradecanoyl-phorbol-13-acetate: TPA) stimuli. Trifluoperazine sulfoxide (TFP-S) and chlorpromazine sulfoxide (CPZ-S), which have very low affinity to CaM, had practically no inhibitory effect on histamine release from human basophils. The inhibitory effect of TFP could be made irreversible by irradiating the cells with UV light. A sulfonamide derivative, the compound N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride (W-7) (2.5 X 10(-5)-2 X 10(-4) M), which selectively binds to CaM, inhibited the release of histamine from basophils. In contrast, the chloride deficient analogue, W-5, which interacts only weakly with CaM, had practically no inhibiting effect. The IC50 for enzyme release by a series of eight CaM antagonists was closely correlated (r = 0.91; p less than 0.001) with the CaM specific binding, supporting the concept that these agents act by binding to CaM and thereby inhibiting histamine release. TFP and W-7 inhibited histamine release in the absence and in the presence of increasing concentrations of extracellular Ca2+. These results emphasize the possible role of CaM in the control of histamine secretion from human basophils.

Basophils↗
PubMed1986

Forskolin inhibits the release of histamine from human basophils and mast cells.

We found that forskolin (10(-7) to 3 X 10(-5) M) caused dose-related inhibition of antigen-induced histamine release from human basophil leukocytes. The dose-response inhibition curve was paralleled by a forskolin-induced increase in cyclic AMP (cAMP) levels in human leukocyte preparations. The kinetics of inhibition of histamine release and of the increase in leukocyte cAMP were the same. In a second series of experiments we evaluated the effect of forskolin on antigen-induced histamine release from chopped human lung passively sensitized with serum from an allergic patient. Forskolin (10(-7) to 3 X 10(-5) M) dose-dependently inhibited the release of histamine from human lung mast cells. Thus forskolin appears to modulate the release of mediators of the immediate hypersensitivity reaction, presumably through activation of adenylate cyclase in human basophils and mast cells.

Adult↗