Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BASOPHILS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 397 records · Page 22Linked to original sources
PubMed2001

The stripped basophil histamine release bioassay as a tool for the detection of allergen-specific IgE in serum.

BACKGROUND: For the detection of allergen-specific IgE in serum, IgE-binding assays such as the radioallergosorbent assay (RAST) are commonly used. In this study, the applicability and sensitivity of the stripped basophil histamine release bioassay was investigated and compared to the RAST. METHODS: Basophils were stripped of their IgE by an acidic buffer, sensitized by human serum and stimulated by allergen with or without interleukin (IL)-3. The histamine release was determined by fluorometric analysis. RESULTS: We showed that for enhancement of the maximal histamine release and the sensitivity of the stripped basophil assay, the priming cytokine IL-3 can be added to the basophils simultaneously to the stimulus. Preincubation of the cells with IL-3, as described in other studies, was not necessary. The bioassay can be used to study the specificity of IgE-mediated reactions. Basophils sensitized by serum absorbed to a particular allergen did not respond to this allergen anymore. This method is very suitable to study cross-reactivity between allergens. The results obtained in the bioassay were comparable to those obtained in the RAST. Using the RAST, lower concentrations of allergen-specific IgE were detected than in the bioassay. However, sera containing IgE against minor allergenic components were negative in the RAST, but strongly positive in the basophil assay. CONCLUSIONS: The stripped basophil histamine release bioassay is useful to complement and extend serological detection of allergen-specific IgE. Especially with sera containing IgE against minor components, this assay is more suitable than the RAST. Furthermore, in this assay, the dependency of IgE and of allergen-specific IgE in reactions can be studied in more detail.

Allergens↗
PubMed2002

Individual hymenoptera venom compounds induce upregulation of the basophil activation marker ectonucleotide pyrophosphatase/phosphodiesterase 3 (CD203c) in sensitized patients.

BACKGROUND: Bee and wasp venom extracts contain potent allergens capable of inducing severe clinical reactions. To analyze immediate-type hypersensitivity to defined hymenoptera venom components, a recently developed in vitro test was applied that is based on the upregulation of CD203c expression on basophils. METHODS: CD203c expression on blood basophils of 9 healthy donors and 39 patients allergic to bee and/or wasp venom was analyzed by flow cytometry before and after activation with the purified bee venom allergens phospholipase A2 (Api m 1), hyaluronidase (Api m 2) and melittin (Api m 4), or the purified wasp venom allergens phospholipase A1 (Ves v 1), hyaluronidase (Ves v 2) and the recombinant antigen 5 (Ves v 5). Venom-induced CD203c upregulation on basophils was compared with skin tests and assessment of specific IgE. Basophils of nonresponders were preincubated with 10 ng/ml interleukin-3 (IL-3) prior to allergen stimulation. RESULTS: CD203c upregulation on basophils was induced by defined hymenoptera venom components in 35/39 patients with a diagnosed allergy to wasp and/or bee venom. Twenty-seven of the 34 tested patients with wasp allergy showed CD203c upregulation in response to Ves v 5, 26 of these patients also reacted with Ves v 2 and 17 with Ves v 1. Nine of 13 patients with bee allergy reacted with Api m 1, 13 individuals with Api m 2 and none of these patients with the minor allergen Api m 4. A diagnosed wasp allergy could also be confirmed in the prestimulated basophils (IL-3) of 2 nonresponder individuals who failed to upregulate CD203c in response to IgE receptor cross-linking prior to culture with IL-3. CONCLUSIONS: Flow-cytometric determination of CD203c upregulation on basophils activated by molecularly defined allergens is a powerful method to identify the precise allergen reactivity in sensitized individuals.

Adolescent↗
PubMed2003

A novel assay to measure the calcium flux in human basophils: effects of chemokines and nerve growth factor.

The calcium flux in human basophils was measured by flow cytometry. Peripheral blood mononuclear cells were labeled with anti-CD123 and anti-HLA-DR antibodies, loaded with fluo-3 acetoxymethyl ester (2 micromol/l) in the presence of probenecid (2.5 micromol/l) and Pluronic F-127 (0.02%) for 20 min, and equilibrated with Ca(2+) (1.8 mmol/l) and Mg(2+) (1 mmol/l) for 5 min. The levels of intracellular free calcium were monitored as changes in fluorescence. Cross-linking of surface IgE on basophils with anti-IgE antibodies caused effective calcium flux in atopic, but not in healthy, donors. Concentration-dependent responses to monocyte chemoattractant protein 1 (MCP-1), eotaxin, macrophage inflammatory protein 1 alpha (MIP-1alpha), and C5a (0.3-10 nmol/l) were observed in all subjects, with a rank order of potency of C5a = MCP-1 > eotaxin > MIP-1alpha. In contrast, the rank order of potency in causing basophil shape change (i.e., increase in forward scatter) was eotaxin > C5a > MCP-1 > MIP-1alpha. Nerve growth factor (NGF; 15 nmol/l) did not induce calcium flux in basophils, and pretreatment of cells with a low concentration of NGF (0.3 nmol/l), which has previously been shown to prime basophils for mediator release, had no effect on the calcium response to subsequent stimulation with C5a. We conclude that calcium mobilization is differentially involved in signaling to chemoattractants in basophils and that it is correlated with the agonist's efficacy to induce mediator release. The data also suggest that priming of basophil responses by NGF does not rely on enhanced calcium mobilization.

Basophils↗
PubMed2004

Flavonoids such as luteolin, fisetin and apigenin are inhibitors of interleukin-4 and interleukin-13 production by activated human basophils.

BACKGROUND: We have previously shown that fisetin, a flavonol, inhibits IL-4 and IL-13 synthesis by allergen- or anti-IgE-antibody-stimulated basophils. This time, we investigated the inhibition of IL-4 and IL-13 production by basophils by other flavonoids and attempted to determine the fundamental structure of flavonoids related to inhibition. We additionally investigated whether flavonoids suppress leukotriene C4 synthesis by basophils and IL-4 synthesis by T cells in response to anti-CD3 antibody. METHODS: Highly purified peripheral basophils were stimulated for 12 h with anti-IgE antibody alone or anti-IgE antibody plus IL-3 in the presence of various concentrations of 18 different kinds of flavones and flavonols. IL-4 and IL-13 concentrations in the supernatants were then measured. Leukotriene C4 synthesis was also measured after basophils were stimulated for 1 h in the presence of flavonoids. Regarding the inhibitory activity of flavonoids on IL-4 synthesis by T cells, peripheral blood mononuclear cells were cultured with flavonoids in anti-CD3-antibody-bound plates for 2 days. RESULTS: Luteolin, fisetin and apigenin were found to be the strongest inhibitors of both IL-4 and IL-13 production by basophils but did not affect leukotriene C4 synthesis. At higher concentrations, these flavonoids suppressed IL-4 production by T cells. Based on a hierarchy of inhibitory activity, the basic structure for IL-4 inhibition by basophils was determined. CONCLUSIONS: Due to the inhibitory activity of flavonoids on IL-4 and IL-13 synthesis, it can be expected that the intake of flavonoids, depending on the quantity and quality, may ameliorate allergic symptoms or prevent the onset of allergic diseases.

Animals↗
PubMed1977

Estimation of basophil-bound IgE by quantitative immunofluorescence microscopy.

By means of a previously developed basophil staining and fixation technique, it was possible to identify human basophilic granulocytes in leukocyte suspensions, which had been subjected to an immunofluorescence technique with anti-IgE. Using fluoresceinated anti-IgE, the fluorescence intensity of the basophils was measured by means of microfluorometry as a reflection of the IgE-load per cell. The reproducibility of this technique and the influence of the incubation time were studied. The mean fluorescence intensity of the basophil varied considerably in six donors, but the cells of two atopic patients showed the highest intensity. IgE was eluted from the cells at pH 2.5 and measured in the supernatant. A correlation was found between the amount of eluted IgE per basophil and the mean fluorescence intensity of the basophils. The number of IgE molecules per basophil was found to be in the range of 15,000--500,000.

Basophils↗
PubMed1981

Antigen-induced histamine release from guinea pig basophils.

Guinea pig blood was found to contain an average of 106 +/- 21 ng/ml of histamine. Of this total, approximately 85-90% was of platelet origin and the rest from basophils. Basophils contain about 0.72 pg of histamine/cell. Concanavalin A (1-5 microgram/ml) induced the release of approximately 65% of the basophilic histamine. When basophils were isolated from animals sensitized to ovalbumin or keyhole limpet hemocyanin, addition of the appropriate antigen induced histamine release at concentrations of 0.01 microgram/ml or lower. Individual animals were studied over time by repetitive bleeding. The circulating basophils remained sensitized for at least 17 weeks postsensitization. However, release did not occur if animals had been sensitized less than 7 days earlier. This assay facilitates the investigation of basophil sensitization since animals can be studied on several occasions following immunization. The mechanisms, timing and role of basophil sensitization in various types of immune and hypersensitivity reactions can now be evaluated.

Animals↗
PubMed1988

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.

Antibodies, Anti-Idiotypic↗
PubMed1992

Hemopoietic growth factors regulate the survival of human basophils in vitro.

Human basophils were purified from normal peripheral blood, using density gradient followed by negative panning selection. We tested the effects of hemopoietic growth factors on the survival of these basophils in vitro. In the absence of exogenous factors, basophils (purity greater than 90%) decreased in number rapidly. At day 7 only 11% of the cells remained alive in cultures; less than 1% of cells survived at day 14. Interleukin (IL)-3 maintained numbers of viable cells; cell viability was 67% at day 7 and 45% at day 14. Granulocyte-macrophage (GM)-colony-stimulating factor (CSF) exhibited slight effect on the survival; 33% of cells remained at day 7. Other growth factors including granulocyte (G)-CSF, macrophage (M)-CSF, and IL-4 had no significant effect on the survival of basophils at all. Morphological and functional characterization of cells maintained by IL-3 revealed that they belonged to the basophil lineage. These observations indicate that normal basophils possess functional receptors for IL-3 and GM-CSF and that both factors modulate immediate- and delayed-type hypersensitivity reactions by prolonging the life span of basophils.

Basophils↗
PubMed1993

Basophil releasability in patients with hymenoptera venom allergy.

Basophils in about 15% of subjects allergic to hymenoptera venom do not release histamine in the presence of antigen. Little is known on the basophil releasability in these patients. We therefore measured maximum percent leukocyte histamine release to antigen (Vespula venom), anti-IgE and formylmethionylphenylalanine (FMP) in 39 patients allergic to wasp venom and compared our results according to basophil responsiveness to antigen. Mean maximum percent histamine release was 39, 34 and 22%, respectively, for venom (100 ng/ml), anti-IgE (0.25 microgram/ml) and FMP (10(-4) M). The amount of histamine specifically released by venom correlated significantly with anti-IgE but not with FMP-induced histamine release. Leukocytes were unresponsive to antigen in 10 subjects. The clinical characteristics and anaphylactic symptoms of these patients were not different from those with antigen-responsive cells. Unresponsive leukocytes responded to FMP in all and to anti-IgE in 8 of the 10 subjects. Mean anti-IgE and FMP-induced histamine release were, respectively, lower and higher than those observed with leukocytes responsive to antigen (p < 0.05). In unresponsive basophils, there was a negative correlation between maximum percent anti-IgE and FMP-induced histamine release. We confirm that basophils of a minority of the subjects allergic to Vespula venom do not release histamine in the presence of antigen. The negative correlation between anti-IgE and FMP-induced histamine release in unresponsive basophils may suggest individual differences in the ratio of Fc epsilon RI and FMP receptors on the surface of basophils.

Adolescent↗
PubMed1996

Basophil histamine release and leukotriene production in response to anti-IgE and anti-IgE receptor antibodies. Comparison of normal subjects and patients with urticaria, atopic dermatitis or bronchial asthma.

The IgE receptor-dependent in vitro mediator release in basophils is characterized by a large interindividual variability both in normal and atopic subjects. The mechanism and the clinical impact of this finding, however, is largely unclear. The aim of the present study was to examine the role of surface-bound IgE and of response-modifying cytokines such as interleukin 3 (IL-3) as possible factors determining basophil releasability in atopic patients and normal controls. Cells from 30 individuals (6 with urticaria, 7 with asthma, 7 with atopic dermatitis, and 30 healthy controls) were isolated and stimulated for mediator release by IL-3 and different triggering antibodies directed against IgE or IgE receptor. Our data suggest that serum IgE levels and basophil receptor occupancy with IgE are not involved in the mechanism of basophil releasability. Furthermore, IL-3-induced similar effects on mediator release in almost all individuals, rather excluding the possibility that releasability is regulated by cytokine priming of basophils. Interestingly, we found that patients with atopic disease have a reduced capacity of releasing mediators upon activation, the mechanism of which is unclear. In conclusion, our findings support the hypothesis that basophil releasability is dependent on cell-imminent mechanisms in basophils, which may be altered in selected atopic patients.

Adult↗
PubMedDate not supplied

Regulation of cytokine expression by human blood basophils.

IL-4 and IL-13 are key immunoregulatory cytokines because of their ability to induce and amplify Th2-type immune responses and by promoting IgE formation. The basophil is a particularly prominent source of IL-4/IL-13, which are rapidly produced upon Fc epsilonRI cross-linking. Cytokine expression by basophils is unique and distinct from other cell types, since: (1) Basophils are the only cell type constitutively expressing IL-4 and IL-13 mRNA. IL-4/IL-13 message and protein are expressed in a very restricted manner, since neither the mRNAs nor the protein products of most proinflammatory Th1-type, and even Th2-type, cytokines or chemokines are expressed; (2) Basophils secrete IL-4/IL-13 also upon IgE-independent activation (IL-3 plus C5a), and they are thereby potentially capable of initiating a Th2 response. Furthermore, we identified an adjuvant from helminths capable of directly inducing IL-4 formation, and (3) IL-4 expression by basophils is resistant to counter-regulatory effectors inhibiting Th2 development. Studies about the regulation of IgE-dependent and -independent IL-4/IL-13 expression by different cytokines, growth factors and chemokines demonstrate that the different basophil effector functions such as chemotaxis, exocytosis, leukotriene C4 formation and cytokine expression are regulated separately. Thus, our study supports a key immunoregulatory role of basophils in the skewing of immune responses to Th2.

Basophils↗
PubMed2000

Increased numbers of both airway basophils and mast cells in sputum after allergen inhalation challenge of atopic asthmatics.

Mast cells and basophils are metachromatic cells that participate in allergic inflammation. Allergen challenge to the airways of atopic asthmatic individuals increases levels of metachromatic cells, which may reflect an increase in mast cells, basophils, or both. We conducted a study to characterize the kinetics of basophil and mast cell recruitment to the airways of atopic asthmatic subjects after allergen inhalation challenge, using monoclonal antibodies specific for each type of cell. Of 19 subjects, 14 developed both early- and late-phase asthmatic responses (dual responders [DRs]), whereas five developed only early asthmatic responses (early responders [ERs]) after allergen inhalation. There was a significant increase in the number of sputum eosinophils (p < 0.002) and basophils (p < 0.002) at 7 h and 24 h after challenge in both ERs and DRs. There was also a significant increase in the number of activated eosinophils (p = 0. 00002) and mast cells (p = 0.009) in sputum at 7 h and 24 h after challenge in DRs, but not in ERs (p > 0.4). DRs had a significantly higher number of allergen-induced sputum basophils than did ERs (p < 0.01), and sputum basophils correlated significantly with airway hyperresponsiveness (AHR) to methacholine at 24 h after challenge (r = 0.66, p = 0.002). DRs tended to have higher allergen-induced basophil levels than did ERs, which may contribute to the observed AHR.

Adult↗
PubMed1989

The effect of parainfluenza 3 infection on guinea pig basophil and lung mast cell histamine release.

The guinea pig infected with parainfluenza 3 (P-3) has provided an animal model to study mechanisms of virus-induced asthma and airway hyperreactivity. Evidence to identify the mechanisms by which P-3 infection enhances airway hyperreactivity, however, has not been established. The present study evaluated the effect of P-3 infection on histamine release (HR) from isolated peripheral blood guinea pig basophils and lung mast cells. Basophil HR was determined in animals made basophilic with 13 daily intraperitoneal injections of sheep blood. On Day 10 of the sensitization, blood was obtained from all animals, and leukocyte HR was determined to sheep gammaglobulin (SG), which served as the secretagogue. After these baseline studies, the animals were separated into two groups; one was insufflated with P-3 virus and the other with growth medium that did not contain virus. Four days later, animals were killed, basophils and lung mast cells were isolated, HR was determined, and lung tissue was cultured for the presence of virus. In basophils isolated from animals proven to be infected with P-3 virus, we found significantly more histamine released in response to the lower doses of SG and a significant shift in the -log EC50 dose of this antigen causing HR in these cells. Experiments conducted with the calcium ionophore A23187 as the basophil secretagogue in the same experimental design did not demonstrate similar HR findings. Furthermore, a defect in calcium disposition did not account for the enhanced HR from basophils isolated from infected animals. HR from pulmonary mast cells was similar in cells isolated from P-3-infected and control insufflated animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2000

The tyrosine kinases p53/56lyn and p72syk are differentially expressed at the protein level but not at the messenger RNA level in nonreleasing human basophils.

Within the general population, individuals can be found whose basophils do not secrete after stimulation through the immunoglobulin (Ig) E receptor. In this study we compared two groups of donors, those whose basophils responded with 65+/-16% histamine release to an optimal concentration of anti-IgE antibody and those whose basophil response was not statistically different from nonstimulated release (1+/-1%). We show that these so-called nonreleasing basophils have at least 10-fold lower expression of the tyrosine kinases, lyn and syk, but normal expression of the tyrosine kinase Btk when compared with the panel of releasing basophils. Indeed, maximum histamine release correlated with expression of both syk (Spearman rank correlation coefficient [Rs] = 0.98) and lyn (Rs = 0.93). In contrast, equivalent levels of messenger RNA (mRNA) for lyn and syk kinase were found for both groups. By sequencing a critical region in the syk mRNA, our results also demonstrate that the frame shift mutation in syk leading to a premature stop codon which has been observed in other cell types is not present in nonreleasing human basophils. Our results suggest that there may be translational or post-translational regulatory mechanisms specific to the expression of two important FcepsilonRI-associated signaling elements in basophils.

Adult↗
PubMed1997

High expression of the chemokine receptor CCR3 in human blood basophils. Role in activation by eotaxin, MCP-4, and other chemokines.

Eosinophil leukocytes express high numbers of the chemokine receptor CCR3 which binds eotaxin, monocyte chemotactic protein (MCP)-4, and some other CC chemokines. In this paper we show that CCR3 is also highly expressed on human blood basophils, as indicated by Northern blotting and flow cytometry, and mediates mainly chemotaxis. Eotaxin and MCP-4 elicited basophil migration in vitro with similar efficacy as regulated upon activation normal T cells expressed and secreted (RANTES) and MCP-3. They also induced the release of histamine and leukotrienes in IL-3-primed basophils, but their efficacy was lower than that of MCP-1 and MCP-3, which were the most potent stimuli of exocytosis. Pretreatment of the basophils with a CCR3-blocking antibody abrogated the migration induced by eotaxin, RANTES, and by low to optimal concentrations of MCP-4, but decreased only minimally the response to MCP-3. The CCR3-blocking antibody also affected exocytosis: it abrogated histamine and leukotriene release induced by eotaxin, and partially inhibited the response to RANTES and MCP-4. In contrast, the antibody did not affect the responses induced by MCP-1, MCP-3, and macrophage inflammatory protein-1alpha, which may depend on CCR1 and CCR2, two additional receptors detected by Northern blotting with basophil RNA. This study demonstrates that CCR3 is the major receptor for eotaxin, RANTES, and MCP-4 in human basophils, and suggests that basophils and eosinophils, which are the characteristic effector cells of allergic inflammation, depend largely on CCR3 for migration towards different chemokines into inflamed tissues.

Basophils↗
PubMed2001

Immunohistochemical localization and comparison of carboxypeptidases D, E, and Z, alpha-MSH, ACTH, and MIB-1 between human anterior and corticotroph cell "basophil invasion" of the posterior pituitary.

Basophil invasion, i.e., invasion of basophilic corticotrophs from the residual intermediate lobe into the posterior lobe of the human pituitary gland, is believed to be a physiological phenomenon. This study evaluated the distribution of CPE, CPD, CPZ, alpha-MSH, ACTH, and Ki-67 immunoreactivity between human anterior pituitary and basophil invasion of the neurohypophysis. Mild to moderate immunoreactivities for CPE and CPZ were distributed relatively uniformly in the majority of the anterior pituitary cells and basophil invasion. In contrast, only corticotrophs exhibited intense CPD immunoreactivity. Basophil invasion showed similar immunoreactivities for alpha-MSH, ACTH, CPE, and CPZ as corticotrophs in the anterior pituitary, except for CPD, which was detected much less frequently. In the posterior lobe, CPE, CPD, and CPZ were present within the Herring bodies. Although no MIB-1 immunoreactivity was identified in anterior pituitary cells, limited MIB-1 labeling was detected in basophil invasion in five of ten cases. Highly selective expression of CPD in corticotrophs suggests that CPD plays a particularly important role in prohormone (POMC) processing in corticotrophs, with minimal or no significant roles in non-corticotrophs. Evidence that corticotrophs in basophil invasion are undergoing proliferation and are also phenotypically different from their counterpart in the anterior pituitary has further raised the possibility of some neoplastic potential.

Adrenocorticotropic Hormone↗
PubMed1980

Cytochemical localization of arylsulfatase B in rat basophils and mast cells.

Basophils and mast cells possess large metachromatically staining granules which contain sulfated glycosaminoglycans as well as vasoactive compounds. To determine whether these granules might also have lysosomal properties, we used electron microscopy and cytochemistry to localize arylsulfatase B in rat basophils and mast cells. In basophils of bone marrow, enzymatic reaction product was consistently seen in many, but not all, of the basophil granules. In some cells, the enzyme could also be demonstrated in the Golgi region, restricted to a single cisterna and small vesicles. It was never seen in rough endoplasmic reticulum (RER), although the paucity of cells made adequate sampling difficult. In mast cells of bone marrow and the peritoneal cavity, enzymatic reaction product was consistently found in some cytoplasmic granules of varying sizes and shapes where it characteristically rimmed the periphery of the granule just beneath the limiting membrane. It should be emphasized, however, that the majority of granules were not reactive. Reaction product could also be found occasionally in segments of RER, and in the Golgi region with a distribution similar to that of the basophil. The presence of lysosomal arylsulfatase in granules of developing basophils in bone marrow suggests that some basophil granules, like those of neutrophils, eosinophils, and monocytes are primary lysosomes. Some mast cell granules also contain this lysosomal enzyme, although it is not clear from the present data whether these granules are primary or secondary lysosomes.

Animals↗
PubMed1989

Effect of sodium cromoglycate and nedocromil sodium on anti-IgE-induced and anti-IgG4-induced basophil degranulation.

Both anti-IgE and anti-IgG4 induce human basophil degranulation as assessed by toluidine blue staining. Anti-IgG4 has been recently shown to act on the human basophil by a 2-step process: anti-IgG4 induces the release from eosinophils of eosinophil cationic proteins which in turn induce human basophil degranulation. In the present study, we show that sodium cromoglycate and nedocromil sodium have no direct effect on human basophil degranulation but inhibit the anti-IgG4-induced degranulation. This effect was dose-dependent and significant inhibitions were obtained at 2.5 to 25 mumol/L for sodium cromoglycate and 25 mumol/L for nedocromil sodium. No drug effect was observed on the basophil degranulation induced by supernatants from anti-IgG4-stimulated eosinophils. However, the release of basophil degranulating factors (eosinophil cationic proteins) by anti-IgG4 from purified eosinophils was significantly inhibited after preincubation with 25 mumol/L of sodium cromoglycate or nedocromil sodium. Taken together, these results indicate that both sodium cromoglycate and nedocromil sodium have an inhibitory effect on the first step of anti-IgG4-induced human basophil degranulation, thus strongly suggesting that these drugs inhibit the release of eosinophil cationic proteins from human eosinophils.

Animals↗