Induction of Histamine Release and Desensitization in Human Leukocytes

Protein A from Staphylococcus aureus has been found to react with all human leukocyte preparations tested. In 70 percent of the experiments the reaction leads to histamine release. Furthermore, protein A treatment of cells at 37 degrees C, both in complete and Ca-2+-free medium, results in the inhibition of anti-IgE-induced histamine release in all cell preparations, indicating that protein A and anti-IgE antibodies release histamine from the same cells. This inhibition seems to be due to the blocking or exhaustion of a step in the biochemical pathway, leading to histamine release activated by both protein A and anti-IgE. In some cell preparations desensitization but no histamine liberation is induced by protein A. No inhibition occurs if the protein A treatment is performed at 4 degrees C. It is concluded that protein A elicits histamine liberation and desensitization by acting on IgG present on the surface of the basophil granulocytes. Treatment of leukocytes at 37 degrees C with anti-IgE antibodies, or F(ab)2 fragments from such antibodies, also results in an inhibition of a subsequent anti-IgE-induced histamine release. Desensitization with low doses of anti-IgE results in an inhibition of the same type as that obtained with protein A. Supraoptimum amounts of anti-IgE or high amounts of monovalent Fab fragments from anti-IgE immunoglobulin G give an inhibition that could be due to a competition between the sensitizing and the challenging agents for combining with cell fixed IgE molecules. This inhibition is independent of temperature and calcium concentration.     

Lymphocyte Activation and Regulation of Three Adhesion Molecules with Supposed Function in Homing: LECAM-1 (MEL-14 Antigen), LPAM-1/2 (α4-Integrin) and CD44 (Pgp-1)

Directed migration of lymphocytes from blood into lymph nodes and gut-associated lymphatic tissue, also referred to as homing, is subject to change following activation. Lymphocyte migration into lymphoid organs in vivo and binding to high endothelial venules in vitro is largely suppressed after short-term stimulation with phorbol esters. The observed functional alterations were correlated with changes in the expression of three putative homing receptors, LECAM-1 (MEL-14 antigen), LPAM-1/2 (alpha 4-integrin) and the murine CD44 (Pgp-1, H-CAM, Hermes-antigen equivalent) upon different modes of cellular activation. Expression of LECAM-1 (gp90 MEL-14), a lymphocyte adhesion molecule implicated in targeting extravasation into lymph nodes, was found to be lost almost completely within minutes after protein kinase C activation. LECAM-1 re-expression occurred within less than 24 h. Rapid loss of LECAM-1 was also observed after calcium ionophores whereas anti-CD3 or concanavalin A elicited a gradual and heterogeneous loss of LECAM-1 becoming detectable after several hours only. A number of cytokines tested were not able to induce alterations in LECAM-1 expression. In contrast, expression of LPAM-1/2 (alpha 4-integrin) and CD44 (Pgp-1, H-CAM), two adhesion molecules supposed to direct extravasation into Peyer's patches, remained stable for hours after every stimulus tested; CD44 expression gradually increased 24 h after mitogenic activation, whereas a small reduction only was observed for the expression of the alpha 4-chain under certain conditions. Thus, reduced extravasation of lymphocytes into Peyer's patches after activation is not due to a decline in the surface density of LPAM-1/2 alpha-chain or CD44 whereas alterations in migration into lymph nodes parallel the expression of LECAM-1.     

Basophil Histamine Release in Cord Blood Regulatory Role of IgE

Thirty-two cord blood samples were studied for histamine releasing capability by using a sensitive glass microfibre-based histamine analysis. Histamine was obtained after challenge with anti-IgE in 24 of the 32 samples. However, the net release in cord blood was only 25% of that in adult blood and no relationship was found between histamine release response, total IgE in cord plasma, and a family history of atopic diseases. The low histamine release in cord blood seemed to be associated with the immunological IgE receptor complex activation and not with an immature basic cell function, since the calcium ionophore A23187 which bypasses the receptor complex induced identical histamine release curves in cord and adult blood. Furthermore, when comparing the results of passive sensitization of basophils from new-born and adult persons, the new-born basophils possessed a significant fraction of free IgE receptors, whereas in adults most of the receptors were occupied by IgE.     

Ischemia-reperfusion injury and histamine release in isolated guinea-pig heart: The role of free radicals

Free radicals produced by the occlusion and opening of the left anterior descending coronary artery and/or by perfusion of isolated guinea-pig heart with FeCl₃/ADP (10 M/100 M) induce a differential release of histamine and lactate dehydrogenase (LDH) in the perfusates with a preferential liberation of histamine in the reperfusion phase, associated with an increase of ventricular arrhythmias. The release of histamine has been correlated with malonyldialdehyde (MDA) production and tissue calcium content in left ventricular tissue. MDA increased during ischemia, while the calcium content increased when the tissue was reperfused. Under these conditions, N-t-butyl--phenylnitrone (BPN), a molecule capable of forming spin adducts with free radicals, andd-mannitol are active in preventing reperfusion-induced arrhythmias.     

Chemical constituents of diesel exhaust particles induce IL-4 production and histamine release by human basophils

BACKGROUND: An epidemiologic relationship between airway allergic diseases and exposure to atmospheric pollutants has been demonstrated and suggested to be one factor in the increasing prevalence of asthma. Diesel exhaust particles (DEPs) have been shown to participate in the development of allergic airway inflammation, in which the targets include macrophages, B and T cells, epithelial cells, and mast cells. In addition to the adjuvant effect of DEPs on total and allergen-specific IgE production, DEPs also act to induce chemokines and cytokines and may play a key role in primary sensitization. OBJECTIVE: DEPs have been shown to increase local IL-4-containing Kit(+) cells soon after in vivo nasal challenge. The aim of this study was to examine the effects of DEPs on human basophils, a key source of IL-4. METHODS: Peripheral blood leukocytes from allergic and control subjects were cultured in the presence of organic extracts of DEP (DEPex) with or without allergen. The cultures were analyzed for IL-4-containing cells by using multiparameter flow cytometry, IL-4 secretion with ELISA, and histamine release. RESULTS: Basophils, when exposed in vitro to DEPex, expressed IL-4 and released histamine significantly (P <.01) more than with antigen activation. DEPex did not synergize with allergen in cytokine production and histamine release. DEPex-induced basophil IL-4 expression peaked at 2 hours and persisted through 20 hours, in contrast to allergen-induced IL-4, which was transient. The effect of DEPex on basophil cytokine expression and histamine release was dose dependent and occurred with cells from both allergic and nonallergic subjects. DEPex induced IL-4 expression and histamine release in highly enriched basophil populations, suggesting it acts directly on basophils. Other peripheral blood leukocytes, including T cells, did not contribute to this cytokine expression. Preincubation with N-acetylcysteine completely abrogated DEPex-driven basophil IL-4 expression. CONCLUSIONS: Basophils are a direct target for DEPex, inducing IL-4 expression and histamine release in an IgE-allergen independent fashion. N-acetylcysteine inhibition of DEPex-driven IL-4 expression provides evidence that generation of reactive oxygen species is required for the effects observed. The capability of DEPex to activate basophils in both allergic and nonallergic subjects suggests a potential role of this pollutant in the increasing prevalence of allergic diseases.     

Helicobacter pylori potentiates histamine release from rat serosal mast cells

We have studied the effect ofHelicobacter pylori (H. pylori) and its bacterial products on mast cell histamine release evoked by compound 48/80, calcium ionophore A 23187 and cholic acid. No significant histamine release is obtained when the various bacterial preparations ofH. pylori are incubated alone with mast cells, but the release of histamine is dose-dependently and significantly enhanced when whole washed and formalin killed cells or crude cell walls are incubated with compound 48/80, calcium ionophore A 23187 or cholic acid. Crude cell walls show the highest activity whereas the filtered supernatants from broth cultures are consistently inactive.The present results indicate a link betweenH. pylori and histamine release and suggest a further involvement of gastric mucosal mast cells in the pathogenesis ofH. pylori-associated gastritis. However, these data need to be extended before any clinical implications can be drawn.     

Comparison of mechanisms of IL-3 induced histamine release and IL-3 priming effect on human basophils

We have investigated the mechanisms by which interleukin-3 (IL-3) induces histamine release and primes basophils for increased histamine release in response to anti-IgE- and N-formyl-methionyl-leucyl-phenylalanine (fMLP). The responsiveness of basophils from atopic donors was variable, only 5/11 subjects showing release of > 10%, to IL-3 in the range 0.1-100 ng/ml. IL-3-induced histamine release required both extracellular Ca2+ and cell membrane IgE, removal of membrane IgE by lactate stripping or desensitization of basophils by incubation with anti-IgE in a Ca2+-free medium blocking IL-3-induced histamine release. IL-3 also primed basophils for histamine release by anti-IgE and fMLP in the same concentration range as it evoked histamine release. When IL-3 and either anti-IgE or fMLP were combined, the result was additive or supra-additive depending on the basophil donor. Unlike IL-3-evoked histamine release, IL-3 priming of basophils for fMLP-induced histamine release was shown to be independent of the presence of both cell surface IgE and of extracellular calcium. The protein kinase C (PKC) inhibitor, staurosporine (10 nM), inhibited anti-IgE induced histamine release, but neither IL-3 induced histamine release nor IL-3 priming of IgE- and fMLP-induced histamine release. Pertussis toxin (1.0 microg/ml) inhibited fMLP-induced histamine release but not anti-IgE-induced histamine release, IL-3-evoked histamine release or IL-3 priming. These results indicate that IL-3 modulates mediator release from human basophils by two mechanisms; a direct release of histamine which involves cell surface IgE and the influx of extracellular calcium but which is unlikely to proceed by the same mechanism as cross-linkage of IgE, and a priming effect which is independent of IgE and extracellular Ca2+ and which enhances the secretory effects of a wide range of unrelated secretagogues.     

The influence of tetradecanoyl-phorbol-acetate (TPA) on histamine release from isolated rat mast cells

A detailed investigation of the influence of tetradecanoyl-phorbol-acetate (TPA) on isolated rat mast cells was undertaken in order to explore the possible involvement of protein kinase C in histamine release. TPA alone could induce histamine release in a medium without calcium, whereas 1 mM CaCl₂ suppressed the release. TPA in combination with a low concentration of the ionophore A23187 induced a considerable histamine release. Preincubation with TPA followed by incubation with the ionophore induced a similar release at low concentrations of TPA (2.5 nM) whereas the response was reduced at higher concentrations of TPA. The inhibition after preincubation with TPA was almost at a maximum within 2 min and was due to a decreased rate of release. TPA could also increase antigen-induced histamine release. After preincubation the potency of low concentrations of TPA increased, whereas higher concentrations (50 nM) became inhibitory. The effects of preincubation were almost fully expressed after 2 min and were not due to altered kinetics of the release. The interaction of oleoylacetylglycerol (OAG) with the ionophore A23187 and with antigen resembled that of TPA, but OAG was considerably less potent. Preincubation with TPA was inhibitory to the histamine release induced by compound 48/80, particularly in the absence of calcium. The release induced by TPA and the ionophore or antigen was calcium-dependent and energy-requiring, and the effects of TPA persisted after washing the cells before exposure to antigen or the ionophore. Preincubation with the protein kinase C inhibitor isoquinolinesulfonyl-methylpiperazine (H-7) slightly enhanced the histamine release induced by the combination of TPA and the ionophore. The suppression exerted by preincubation with TPA on ionophore- and antigen-induced release was counteracted by H-7. The results indicate that only the inhibitory effects of protein kinase C are affected by H-7. Although not conclusive, the results are compatible with an involvement of protein kinase C in both the enhancing and the inhibitory effects of TPA on mast cell histamine release.Parts of this investigation were presented at the meeting of the European Histamine Research Society in May 1986.     

Characteristics of histamine release from rat mast cells in relation to the valency of the stimulating ligand.

The relationship between the valency of a ligand and the subsequent characteristics of histamine release was investigated in rat peritoneal mast cells. The cells were passively sensitized to the DNP hapten and a series of DNP-human serum albumin conjugates of known valency were used to induce histamine release. The rate of release of histamine induced by these conjugates was independent of the DNP/HSA ratio when the ratio was between 71.3 and 7.2. Marked slowing of the release occurred as the ratio was reduced below 7.2. The rate of desensitization of the cells slowed as a continuous function as the DNP/HSA ratio was reduced. 45Calcium uptake measurements showed that the changes in histamine release were paralleled by changes in the membrane permeability to calcium. The rate of release of histamine from mast cells and the rate of desensitization of the cells are discussed in terms of the size of IgE receptor complexes on the cell membrane.     

Inhibition of basophil histamine release by gangliosides

Histamine release from human basophils was inhibited by preincubation of the cells with a glucolipid mixture containing sialic acid-containing gangliosides. This was true for histamine release induced by anti-IgE, Concanavalin A and the calcium ionphore A23187, whereas the release induced by S. aureus Wood 46 was not affected. It was demonstrated that the inhibitory capacity of the glucolipid mixture could be attributed to the content of gangliosides, since no inhibition was obtained with cerebrosides or with gangliosides from which sialic acid was removed. Preincubation of the cells with the glucolipid mixture increased the sialic acid content of the cells, and this increase was attributed to an insertion of gangliosides into the cell membrane. The inhibition of histamine release was abolished by increasing the calcium concentration, which substantiates our previous findings that cell membrane sialic acid in basophil leukocytes is involved in the regulation of histamine release, possibly by a modulation of the trans-membraneous calcium fluxes preceding histamine release.     

Roles of histamine, complement and xanthine oxidase in thermal injury of skin.

The pathogenesis of burn edema in the skin of rats appears to be related to a role for histamine, xanthine oxidase and oxygen radicals. Histamine and its metabolic derivatives increase the catalytic activity of xanthine oxidase (but not xanthine dehydrogenase) in rat plasma and in rat pulmonary artery endothelial cells. In thermally injured rats levels of plasma histamine and xanthine oxidase rise in parallel, in association with increases in uric acid. Burn edema is greatly attenuated by treatment of rats with the mast cell stabilizer, cromolyn, by complement depletion and by treatment with the H2 receptor antagonist, cimetidine, but is unaffected by neutrophil depletion. These studies suggest the following pathogenesis of burn edema: thermal trauma causes complement activation with anaphylatoxin release and mast cell secretion of histamine, leading to enhancement of xanthine oxidase activity and increased production of oxygen radicals which damage endothelial cells.     

Effect of sodium sulfite on mast cell degranulation and oxidant stress.

BACKGROUND: Sulfur dioxide is 1 of 6 environmental pollutants monitored by the Environmental Protection Agency. Its ability to induce bronchoconstriction is well documented. It is highly soluble, initially forming sulfite ions in solution. Sulfur oxides are important constituents of other pollutants, such as diesel exhaust and fine particulates. OBJECTIVE: To investigate the cellular responses of sulfite on cultured mast cells (rat basophilic leukemia [RBL-2H3] cells) and human peripheral blood basophils. METHODS: Sulfite-induced mast cell degranulation and intracellular production of reactive oxygen species were evaluated in the presence and absence of antioxidants and inhibitors of redox metabolism. Degranulation was determined using beta-hexosaminidase, serotonin, and histamine release assays. Induction of intracellular reactive oxygen species generation was determined using the redox-sensitive dye 2',7'-dichlorofluorescein diacetate. RESULTS: Sodium sulfite induced degranulation and the generation of intracellular reactive oxygen species in RBL-2H3 cells. These responses were inhibited by the free radical scavenger tetramethylthiourea and the flavoenzyme inhibitor diphenyliodinium but not by depletion of extracellular calcium. Peripheral blood basophils also showed histamine release after exposure to sodium sulfite CONCLUSIONS: Sulfite, the aqueous ion of sulfur dioxide, induces cellular activation, leading to degranulation in mast cells through a non-IgE-dependent pathway. The response also differs from IgE-mediated degranulation in that it is insensitive to the influx of extracellular calcium. The putative pathway seems to rely on activation of the reduced form of nicotinamide adenine dinucleotide phosphate oxidase complex, leading to intracellular oxidative stress.     

Histamine release from saponin-permeabilized rat mast cells by calcium

The first effect of receptor activation on the mast cell surface, initiating histamine secretion, is an increase in the cytosol Ca²⁺ concentration. It should then be possible to induce histamine secretion by calcium alone, if the calcium permeability of the cell membrane could be increased without any significant interference with the physiological cell functions. This was achieved in the present study by adding low concentrations of saponin (0.005% and 0.001% w/v) to the medium. When calcium was added to the saponinpermeabilized cells, around 40% histamine release occurred with 0.25 mM extracellular calcium (free Ca²⁺ 0.15 mM). The release was inhibited by antimycin A (1 M). Transmission electron microscopy showed formation of vacuoles containing granules stripped of their membranes, which characterize a secretory response. The observations are consistent with a limited increase in the calcium permeability of the cell membrane for a brief period. There was apparently an increase in the cytoplasmic calcium concentration, which acted through calmodulin, since the histamine release induced by calcium from the permeabilized mast cells could be inhibited by a calmodulin-antagonist, mepacrine (10–30 M).     

Histamine liberation and membrane fluidisation of mast cells exposed to the beta-adrenoceptor blocking drug propranolol

Propranolol liberates histamine from isolated mast cells and decreases the uptake of extracellular histamine in a dose-dependent way. Histamine liberation due to propranolol is accompanied by calcium displacement from intracellular storage sites. The significant increase in membrane fluidity due to propranolol is temperature dependent. The perturbation of membranes is most probably the explanation of propranolol's interaction with isolated rat mast cells which results in altered histamine transportation.     

人嗜碱性粒细胞在不同刺激物作用下的组胺释放能力

目的:研究蛋白酶激活受体2(PAR2)激动剂和肝素等,对嗜碱性粒细胞组胺释放的影响。方法:用Ficoll进行密度梯度离心分离外周血单个核细胞(PBMC)。经Hank’s平衡盐溶液(HBSS)重新悬浮后进行嗜碱性粒细胞激发实验,用酶联免疫试剂盒来检测组胺的水平。结果:浓度为10mg/L胰蛋白酶可引起嗜碱性粒细胞释放组胺,其作用强度较抗IgE抗体、钙离子载体(CI)及P物质等为弱。PAR2特异性激动肽SLIGKVNH2对嗜碱性粒细胞没有明显的激活作用,但抗IgE抗体、CI、FMetLeuPhe(FMLP)、C5a及P物质可引起嗜碱性粒细胞显著的组胺释放。肝素、C5和腺苷在试验浓度内未引起组胺释放,但肝素可显著增加C5a和P物质诱导的组胺释放。结论:胰蛋白酶、抗IgE抗体、CI、FMLP、C5a及P物质均可诱导嗜碱性粒细胞显著地释放组胺。PAR2激动肽SLIGKVNH2不能引起组胺释放,肝素可增加P物质和C5a引起的组胺释放,具有放大嗜碱性粒细胞激活信号的作用。     

The role of membrane bound sialic acid of rat mast cells in histamine release induced by compound 48/80 and derivatives as well as calcium

Histamine release induced by compound 48/80 from rat mast cells is not dependent on extracellular Ca²⁺. Preincubation of mast cells with trypsin has only little effects on histamine release induced by this polycation. This work also demonstrates that histamine release induced by compound 48/80 and its analogues in the absence of extracellular Ca²⁺ depends on membrane bound sialic acid of the mast cell. Neuraminidase treatment of the cells in the presence of extracellular Ca²⁺ leads to histamine liberation. These findings suggest that sialic acid residues of the mast cell membrane constitute the site at which polycations exert their stimulatory actions of histamine liberation.     

Differences in the Kinetics of Histamine Formation and Granulation of Human Basophilic Cells from Bone Marrow, Peripheral Blood, and Cord Blood

Human bone marrow, cord blood, and peripheral blood contain progenitor cells, which during culture mature to histamine-containing basophilic cells. In bone marrow the histamine content per Alcian blue staining basophilic cell was low before culture. Cultivation of BML cells resulted in increased histamine levels in cultures (P less than 0.05), whereas the basophilic cells did not increase significantly. Cell cultures were stimulated with conditioned medium (CM) produced with allergen-stimulated cells from atopics and from the Mo T leukaemic cell line. Cells from cultures stimulated with CM contained less histamine calculated per basophilic cell than did those from unstimulated cultures (P less than 0.05). There was a significant correlation between the numbers of basophilic cells and the histamine content in cells on day 0 prior to cultivation and after 14 days of cultivation (P less than 0.01 and P less than 0.05 respectively). In cord blood there was a correlation between the numbers of basophilic cells and the histamine levels prior to cultivation (P less than 0.05). During cultivation the number of basophilic cells increased five-fold (P less than 0.02), whereas the histamine levels did not increase resulting in a decreased histamine level per basophilic cell (P less than 0.02). In peripheral blood the basophilic cells contained the highest levels of histamine. The numbers of basophilic cells and their content of histamine showed good correlation both before and after unstimulated and stimulated cultivation (P less than 0.01), whereas unstimulated cultures did not show such correlation. The results indicate the presence of different proportions of progenitor cells in bone marrow, cord blood, and peripheral blood, all with different ability to produce histamine and become granulated basophilic cells.     

Characterization of rat LECAM-1 (L-selectin) by the use of monoclonal antibodies and evidence for the presence of soluble LECAM-1 in rat sera

We have characterized the rat LECAM-1 (L-selectin) by the use of newly generated hamster anti-rat LECAM-1 monoclonal antibodies (mAb) (HRL1, HRL2, HRL3, HRL4), with respect to the biochemistry, cellular distribution and function, and developed an ELISA system to detect the soluble form of rat LECAM-1. In the rat, lymphocyte and neutrophil LECAM-1 have apparent molecular masses of 65 and 62 kDa, respectively, and differential glycosylation may account for the molecular heterogeneity. Readily detectable levels of LECAM-1 are expressed on peripheral blood lymphocytes and neutrophils, but not on thymocytes. Lymphocyte LECAM-1 is rapidly shed from the cell surface upon cell activation with PMA, but not with interleukin (IL)-8. In contrast, neutrophil LECAM-1 showed rapid shedding upon stimulation with phorbol 12-myristate 13-acetate (PMA) or IL-8. Concomitantly there is up-regulated expression of Mac-1 in PMA- and IL-8-stimulated neutrophils. Neutrophil rolling in mesenteric venules was significantly inhibited by administration of function-blocking anti-rat LECAM-1 mAb HRL3, but not by non-blocking HRL4, indicating that LECAM-1 plays a significant role in leukocyte rolling. Given that LECAM-1 is rapidly shed from the cell surface, we attempted to develop an ELISA system for detecting LECAM-1 is soluble form, and measured the levels in experimental autoimmune uveitis. The circulating levels of LECAM-1 increased from day 4, which preceded the appearance of clinical signs of uveitis and remained high until uveitis subsided, suggesting that soluble LECAM-1 is potentially a useful parameter to monitor certain types of inflammatory or immune disorders.     

Membrane sialic acid influences basophil histamine release by interfering with calcium dependence

The influence of the cell membrane content of sialic acid on basophil histamine release was examinedin vitro in allergic patients and normal controls. Enzymatical removal of sialic acid enhanced histamine release induced by allergen and anti-IgE, whereas an increase in membrane sialic acid content by insertion of sialic acid containing gangliosides into the membrane inhibited the mediator release.The reduction in membrane sialic acid content abolished the inhibitory capacity of the calcium channel antagonist nimodipine, whereas the inhibition produced by verapamil and lanthanum was not affected. This difference, together with the previous finding that alterations in membrane sialic acid content is reflected in the cell sensitivity to extracellular calcium, suggest an interaction between membrane sialic acid and the calcium channels involved in basophil histamine release.     

Cord blood basophil releasability: evaluation of histamine release and leukotriene C4 generation

This study was performed to evaluate mediator (histamine and leukotriene C4) release from cord blood and adult blood basophils, challenged with IgE-independent (calcium ionophore A23187) and IgE-mediated (anti-IgE) stimuli. IgE-independent mediator release was similar in adult blood and umbilical blood basophils. Conversely, the anti-IgE-induced histamine and immunoreactive leukotriene C4 (iLTC4) release was significantly reduced in cord blood basophils. Passive sensitization with an IgE-rich serum was followed by a significant increase in the number of eluted IgE molecules from cord blood basophils and by an increase in IgE-mediated histamine release. iLTC4 production was not affected by passive sensitization of umbilical blood basophils. The IgE-dependent mediator release from cord blood basophils was not correlated with the number of cell-bound IgE. In addition, histamine secretion and leukotriene C4 production from cord blood basophils seem to be independent events.