Basophil histamine release and lymphocyte proliferation tests in latex contact urticaria

Basophil histamine release and lymphocyte proliferation tests were examined with latex allergen prepared from surgical gloves in 15 patients with latex contact urticaria. The basophil histamine release test (BHRT) yielded positive results in 13/14 (93%) patients, whereas commercial latex RAST was positive in only 9/15 (60%) patients. Lymphocyte proliferation test (LPT) was positive in 3/15 (20%) patients, suggesting that cell-mediated immune reactions may also occur in latex allergy. However, patch tests to latex were negative and neither were epidermal Langerhans cells able to present latex antigen to T lymphocytes in vitro.     

Impairment of the inhibitory effect of sodium on basophil histamine release in patients with systemic sclerosis

It has been demonstrated that Na⁺ down-regulates IgE-dependent and IgE-independent histamine release from basophils of normal subjects. The aim of this study was to evaluate whether Na⁺ exerts its inhibitory effect on basophil histamine release in patients with systemic sclerosis (SSc). Peripheral blood leucocytes were stimulated with anti-IgE, n-formyl-methionyl-leucyl-phenylalanine (fMLP) and IL-3 in the presence of high and low Na⁺ concentrations, and histamine release was measured by a fluorometric method. The dose–response curves of histamine release induced by the above stimuli were similar in SSc patients (n = 15) and in normal subjects (n = 39). Na⁺ removal from the extracellular medium and its isosmotic replacement with choline chloride led to a significant increase of anti-IgE-and fMLP-induced histamine release in normal subjects, but not in SSc patients. In the former population, histamine release induced by an optimal dose of anti-IgE (1/5000) was 26.4 ± 3.1% in high Na⁺ and 59.3 ± 3.5% in low Na⁺ (mean ± s.e.m., P< 0.0001), whereas in the latter population mean histamine release was 20.4 ± 5.1% in high Na⁺ and 15.8 ± 2.9% in low Na⁺ (P NS). A similar trend was observed when basophils were stimulated with fMLP. Na⁺ exerted a dose-dependent inhibitory effect on anti-IgE- and fMLP-induced histamine release in normal subjects, but not in SSc patients. IL-3-induced histamine release from basophils of SSc patients was increased in a low-Na⁺ solution, but to a lesser extent when compared with normal controls. Therefore basophils from normal subjects and SSc patients behave in a different way when stimulated in a low-Na⁺ medium. The inhibitory effect of Na⁺ on basophil histamine release is impaired in SSc patients, and this abnormality could contribute to basophil dysfunction.     

In vivo and ex vivo inhibitory effects of loratadine on histamine release in patients with allergic rhinitis

Background The aim of this study was to evaluate the in vivo and ex vivo effects of the H.-antagonist loratadine on histamine release.
Methods The study was designed as a double-blind, crossover trial. Ten patients with allergic rhinitis due to Dermatophagoides pteronyssinus were treated with loratadine (10 mg daily p.o.) and with placebo for 1 week, with a 2-week interval between the two treatments. Nasal lavages with saline solution were done before and after challenge with the relevant allergen at the end of treatments with loratadine and placebo. Venous blood was taken after treatments, and basophil histamine release induced by anti-IgE (10 μg/ml), N-formyl-methionyl-leucyl-phenylalanine (fMLP, 1 μM). and Ca²⁺ ionophore A23187 (1 μM) was evaluated by ati automated fluorometric method.
Results Treatment with loratadine attenuated early antigen-tnduced nasal obstruction, rhinorrhea. and itching. Nasal symptoms were accompanied by a significant histamine release in the nasal lavages collected 5 min after stimulation when the patients received placebo (median 4 ng/ml, range 1-28; P<0.05). After treatment with loratadine, histamine release in the 5-min postchallenge lavages was almost abrogated (median 0.5 ng/ml, range 0-3; P<0.01 vs placebo). Median anti-IgE-induced histamine release from basophils was 41.9% (range 27.8-79.2) after placebo and 30.0% (range 1.7-73.3, P < 0.05) after loratadine. Active treatment exerted an inhibitory effect also on basophil histamine release induced by fMLP and Ca²⁺ ionophore A23187.
Conclusions Treatment for 1 week with loratadine reduces allergen-mduced nasal symptoms and inhibits in vivo and ex vivo histamine release in patients with allergic rhinitis.     

Ex vivo pharmacologic modulation of basophil histamine release in asthmatic patients

Histamine is one of a range of mediators which play an important role in asthma, and the "releasability" of basophils has been shown to be upregulated in this disease. In vitro , β₂-agonists and to a lesser extent corticosteroids have been shown to reduce histamine release. The ex vivo effects of salmeterol and inhaled corticosteroids on histamine release were studied in 78 asthmatic patients with variable disease severity and 20 control subjects. Spontaneous and anti-IgE-induced histamine release was measured in all subjects. Fifteen patients were not receiving any form of treatment, 42 were treated with inhaled corticosteroids, and 21 received inhaled corticosteroids and salmeterol. Seven patients treated with inhaled corticosteroids and seven patients treated with inhaled corticosteroids and salmeterol were tested twice to assess the effect of salmeterol on histamine release. Nine patients treated with inhaled corticosteroids were tested before and after 1 month of salmeterol treatment to determine the possible inhibition by salmeterol. Patients who were treated with inhaled corticosteroids and salmeterol showed significantly lower levels of spontaneous histamine release (median: 2.5%) than untreated (5.2%) and inhaled corticosteroids-treated asthmatics (3.4%). No tachyphylaxis to salmeterol was observed when patients were tested twice at a 3-month interval. This study suggests that salmeterol may have an additive anti-inflammatory effect with inhaled corticosteroids, although this hypothesis must be tested by further studies involving cells obtained by bronchoalveolar lavage and studies with bronchial biopsies.     

Enhanced basophil histamine release and neutrophil chemotactic activity predispose grain dust-induced airway obstruction.

BACKGROUND: The pathogenic mechanism of grain dust (GD)-induced occupational asthma (OA) remains unclear. OBJECTIVE: To understand further the mechanism of GD-induced OA. METHODS: Fifteen employees working in a same GD industry, complaining of work-related respiratory symptoms, were enrolled and were divided into two groups according to the GD-bronchoprovocation test (BPT) result: six positive responders were grouped as group III, nine negative responders as group II and five healthy controls as group I. Serum GD-specific immunoglobulin (Ig)E (sIgE), specific IgG (sIgG) and specific IgG4 (sIgG4) antibodies were detected by enzyme-linked immunosorbent assay. Basophil histamine release was measured by the autofluorometric method, and changes of serum neutrophil chemotactic activity were observed by the Boyden chamber method. RESULTS: For clinical parameters such as degree of airway hyperresponsiveness to methacholine, duration of respiratory symptoms, exposure duration, and prevalences of serum sIgE, sIgG and sIgG4 antibodies, there were no significant differences between group II and III (P > 0.05, respectively). Serum neutrophil chemotactic activity increased significantly at 30 min and decreased at 240 min after the GD-BPT in group III subjects (P < 0.05, respectively), while no significant changes were noted in group II subjects (P > 0.05). Basophil histamine release induced by GD was significantly higher in group III than those of group I or group II (P < 0.05, respectively), while minimal release of anti-IgG4 antibodies was noted in all three groups. CONCLUSIONS: These results suggest that enhanced basophil histamine release and serum neutrophil chemotactic activity might contribute to the development of GD-induced occupational asthma.     

Effect of nitrendipine on histamine release from human basophil leukocytes

The effect of the new calcium antagonist nitrendipine on in vitro basophil activation was evaluated in 10 subjects. The histamine release induced by calcium ionophore A23187, f-met peptide and anti-IgE was inhibited, in a dose-dependent fashion, by nitrendipine in the concentration range of 1-100 microM. The activity of this calcium antagonist seems complex and related to an interference with calcium at multiple sites. At concentrations higher than 200 microM, nitrendipine causes histamine release from basophil leukocytes. This histamine secretion is likely to be due to a cytotoxic effect, since it is associated with an increase in LDH levels in the cell supernatant.     

Basophil histamine release in the diagnosis of house dust mite and dander allergy of asthmatic children

The aim of the study is to compare the glass fibre-based basophil histamine release test with skin test (Phazet), RAST (Phadebas) and bronchial provocation test in children with allergic asthma. The study comprised 68 selected children with a case history of extrinsic allergic asthma to danders (cat and dog) and house-dust mite. Skin prick test, RAST, and histamine release were performed in all children and the bronchial provocation test was used as a reference of "true allergic asthma". A total of 81 allergen bronchial challenges were performed and 44 children experienced 49 positive provocations. In 2.9% (2/68) of the children histamine release could not be performed due to technical difficulties (low histamine release with anti-IgE). Concordances in the range 76-87% were observed with no significant difference between the tests. The highest concordance (87%) was found between histamine release and bronchial provocation test followed by skin prick test vs bronchial provocation (84%) and RAST vs bronchial provocation (80%). The sensitivity and specificity were calculated for each test. All tests showed sensitivities in the range 90-94% and no significant difference between them was observed. The specificity of histamine release, skin prick test, and RAST was 0.78, 0.69, and 0.63, respectively. The specificity of histamine release was better than RAST demonstrated by 95% confidence intervals. In conclusion, it was found that the histamine release test is a convenient diagnostic method and the study indicates a diagnostic value comparable to the common diagnostic methods in clinical allergy.     

Relevance of basophil histamine release changes during venom immunotherapy

We investigated the effect of rush and long-term venom immunotherapy on histamine release parameters in bee venom allergic patients. Ten patients received rush venom immunotherapy, and histamine release data were obtained immediately before and after treatment. 17 patients were assessed by histamine release 24 to 63 months after termination of long-term venom immunotherapy. A control group of 10 non-allergic subjects was included in this study. Histamine released from whole blood was determined in a sensitive radio-enzymatic assay using a single isotope technique. Bee venom phospholipase A-induced histamine release from whole blood proved to be a test procedure of high specificity and sensitivity. Eight of 10 untreated patients and no control subject showed significant antigen-induced histamine release. Results obtained from patients immediately after successful rush venom immunotherapy showed an important decrease (mean 45.9%) of total histamine content of basophil leukocytes in all patients. Antigen-induced maximum histamine release was found to be increased in one, decreased in two and unchanged in seven patients. In patients who received long-term immunotherapy cell sensitivity to phospholipase A was significantly lower than in a group of untreated patients (P less than or equal to 0.002). These results suggest that even years after discontinuation of immunotherapy, histamine release parameters reflect patients' protection from systemic sting reactions as assessed by sting challenges. Histamine depletion of basophils induced by rush immunotherapy may play an important role in patients' protection immediately after termination of the rush regimen.     

Basophil histamine release, IgE, eosinophil counts, ECP, and EPX are related to the severity of symptoms in seasonal allergic rhinitis

BACKGROUND: Serum specific IgE, basophil histamine release, and blood eosinophil parameters are associated with allergic rhinitis, but investigations of the relationship to the severity of allergic symptoms are few and conflicting. Our study aimed to investigate the seasonal changes in the following laboratory tests: specific IgE, basophil histamine release, eosinophil counts, and serum and plasma eosinophil cationic protein (ECP) and eosinophil protein X (EPX), and to analyze, in detail, the relationship of each individual test to the severity of symptoms in rhinitis patients allergic to both birch and grass pollen. METHODS: The above tests were performed on blood samples obtained from 49 allergic rhinitis patients during the birch-pollen season, during the grass-pollen season, and after the seasons. Symptom-medication diaries were filled in during both pollen seasons. We used partial least square (PLS) analysis to establish an optimal statistical link between the symptom score and medication and the laboratory tests, in an investigator-independent way. RESULTS: Increases in specific IgE, basophil histamine release, eosinophil counts, serum ECP and EPX, and plasma EPX were observed from the birch-pollen season to the grass-pollen season, followed by a decrease from the grass-pollen season to after the pollen seasons, except for the specific IgE. No seasonal changes in plasma ECP and total IgE were seen. The PLS analysis found a relationship between symptom score and medication and the aggregate laboratory tests (F-test value 40.2, correlation 0.34 for the cumulative relation). However, the variation in laboratory tests could explain only half of the total variation in symptoms and less than a quarter of the total variation in medication. The symptom score and, to a minor degree, medication were especially correlated with the basophil histamine-release results, with a decreasing relevance of specific IgE, eosinophil counts, total IgE, serum and plasma EPX, and serum ECP. Plasma ECP was not related to the symptom score and medication. CONCLUSIONS: A significant relationship between the severity of allergic rhinitis and various allergic inflammatory markers was found but could account for only a minor part of the variation in the patients' evaluation of their disease.     

Comparison of the action of calcium antagonists on basophil histamine release

The inhibitory capacity of calcium antagonists on basophil histamine release was examined in allergic patients and in controls. All dihydropyridines tested (nifedipine, nimodipine, nitrendipine, nicardipine, felodipine) dose-dependently inhibited anti-IgE- and A23187-induced release with an order of potency of felodipine greater than nicardipine greater than nifedipine = nimodipine = nitrendipine. Only the inhibition induced by felodipine and nicardipine on anti-IgE-induced release could be counteracted by increasing extracellular calcium. Diltiazem, not belonging to the dihydropyridines, was a weak inhibitor. A combination of felodipine and verapamil in low concentrations exerted a synergistic inhibitory effect on histamine release, whereas this was not the case with other combinations of antagonists. The results suggest differences in the mode of action of the 1.4-dihydropyridines. This might be of significance in the search for calcium antagonists suitable in the treatment of allergic diseases.     

Effect of interleukin 2 on basophil histamine release

Accumulating evidence suggests a link between immediate hypersensitivity and cellular immunity. In this study, we examined the effect of interleukin 2 (IL-2) on basophil histamine release. Histamine-releasing activity of IL-2 was very weak with % histamine release of 2.9 +/- 1.3 (mean +/- SEM, n = 9) at 1:12 dilution. IL-2 at 1:1200 dilution slightly inhibited anti-IgE-induced histamine release by 22.4 +/- 18.6% (P greater than 0.05). There was a significant potentiation of release at 1:12 dilution of IL-2 with % enhancement of 78.7 +/- 42.2 (P less than 0.05). IL-2 enhanced the calcium ionophore A23187-induced histamine release in a dose-dependent fashion. IL-2 at 1:12 dilution significantly potentiated release by 28.8 +/- 6.3% (P less than 0.05). There was a slight suppression of formyl-methionyl-leucyl-phenylalanine (FMLP)-induced histamine release at 1:1200 dilution with % inhibition of 23.4 +/- 7.4 (P greater than 0.05). At 1:12 dilution, IL-2 significantly potentiated FMLP-induced release by 73.7 +/- 41.6% (P less than 0.05). Recombinant IL-2 (RIL-2) augmented anti-IgE-induced histamine release with a significant enhancement at 200 units/ml. Conventional IL-2 was more potent than RIL-2 in enhancing release. These results indicate that IL-2 enhances basophil histamine release and some part of the effect of IL-2 on basophils is derived from other factors contained in conventional IL-2.     

Comparison of histamine assay methods in measuring in vitro-induced histamine release in patients with allergic rhinitis

histamine release tests using whole blood were applied in testing in vitro Type I birch allergic reaction in two patients with allergic rhinitis. Heparinized blood was incubated with varying dilutions of allergen for 30 min at +37 degrees C. After centrifugation of the blood, plasma was separated and the liberated histamine was analysed by histamine radio enzyme assay (REA), high performance liquid chromatography (HPLC) with post-column derivatization system or radio immuno assay (RIA), and the results obtained by these methods were compared. REA and HPLC gave similar results, while RIA gave somewhat higher values, but was less sensitive.     

Basophil histamine release in patients with birch pollen hypersensitivity with and without allergic symptoms to fruits

Histamine release (HR) studies were performed in 40 birch pollen-allergic patients (positive case history, positive SPT, positive birch pollen-specific serum IgE: RAST > or = 3) with (n = 20, A) and without (n = 20, B) fruit hypersensitivity, and 10 nonatopic volunteers (C). Several fruit allergens were used and characterized by protein determination and immunoblot techniques. Dose-dependent HR (apple peel = apple pulp > peach = cherry) was demonstrated in both allergic groups, but to a higher extent in patients with fruit allergy (P < 0.01). Increased basophil sensitivity to birch pollen was found in the group with fruit allergy (P < 0.001). Strong correlations between the mediator response induced by several fruits indicate common allergens within the extracts. We conclude that fruit-related symptoms require not only high specific serum IgE, but a strong cellular sensitization to birch pollen allergens together with an increased cellular reactivity to fruit allergens.     

Regulation of histamine release from human basophil leucocytes: role of H1, H2 and H3 receptors

A novel class of histamine receptors (H3), controlling histamine synthesis and release, was described in rat and human brain and peripheral nerve endings. The present study was undertaken to evaluate whether H3 receptors contribute to the regulation of histamine release from human basophils. Basophil leucocytes were incubated with a H3 antagonist (thioperamide; concentrations ranging from 1 nM to 10 microM) or with a H3 ((R)alpha methyl-histamine; concentrations ranging from 1 to 100 mM), and subsequently were stimulated with optimal doses of anti-IgE and formyl-methionyl-leucyl-phenyl-alanine (f-met peptide). No significant modifications of histamine release were observed after incubation either with the H3 agonist or with the H3 antagonist. By contrast, a H2 antagonist (cimetidine; concentrations ranging from 1 to 100 microM) exerted a dose-dependent enhancing effect on anti-IgE- and, to a lesser extent, on f-met peptide-induced histamine release. A H1 antihistamine (chlorpheniramine; concentrations ranging from 100 nM to 1 microM), at the highest concentration employed, displayed an inhibitory activity on IgE-dependent and IgE-independent histamine release. Exogenous histamine was shown to exert a dose-dependent inhibitory effect on two-staged anti-IgE-induced histamine release. Taken as a whole, these results suggest that H3 receptors are not involved in the regulation of histamine release from human basophils; by contrast, H2 receptors participate in controlling histamine release from human basophils, as previously demonstrated by other authors.     

Factors determining spontaneous histamine release from human basophils purified with Percoll gradients and Dynabeads

Identification of factors influencing histamine release from purified and cultured basophil leukocytes is important for proper interpretation of results obtained on histamine release. This paper describes factors that influence spontaneous histamine secretion from human basophil leukocytes purified on Percoll gradients, followed by negative selection with Dynabeads. Anti-IgE and recombinant human interleukin-3 were used as model stimulants, and the purified basophil leukocytes were stimulated for 10 min and 6 h. The effect of the following conditions was examined: Percoll temperature, cell-suspension density, and serum in the media. The results showed that low Percoll temperature, high cell-suspension density, and the presence of serum in the media decreased spontaneous histamine release and increased maximal net histamine release upon stimulation.     

Studies on Hypersensitivity to Bacterial Antigens in Intrinsic Asthma

Twelve children, aged 4 to 14 years, with moderate to severe intrinsic asthma (IA) were studied. Symptom-Score charts were used to confirm the relationship of acute respiratory tract infections to exacerbations of asthma. Hypersensitivity to eight commonly occurring bacteria from the normal flora of the upper respiratory tract was studied by skin test, by crossed immunoelectrophoresis, and by basophil histamine release in vitro, using ultrasonicates of the bacteria as antigens. Skin tests were all negative. All children contained low titers of precipitating antibodies against most of the bacteria, but in this respect they did not differ from normal children. In contrast, release of histamine was induced in leukocytes from the IA children by all, or most sonicates, while such reactions, were less frequent in control children. The pattern of responses indicated an element of specificity. These was no correlation to precipitating antibodies, or to the microbial flora of the children. Positive responses were characterized by low values of maximal histamine release, and by a tendency to fluctuations with time. Because of these fluctuations, and because the IA children and control children were tested on separate occasions, we cannot be certain as to the real difference between these two groups. Our studies do, however, demonstrate that water-soluble constituents of all the bacterial strains tested were capable of causing the release of histamine in vitro, but that this phenomenon is not restricted to IA. The clinical significance of these findings awaits further investigations on the mechanism(s) of release in vitro by such agents.     

Coding single nucleotide polymorphism in the high-affinity immunoglobulin E receptor b chain (Fc"RI-b) gene is associated with immunoglobulin E receptor-mediated histamine release from basophils

BACKGROUND: Our previous work on linkage analysis showed that histamine release from basophils to anti-IgE stimuli was linked to the gene marker of chromosome 11q13, where the beta chain of the high-affinity receptor for IgE (FcepsilonRI-beta) is located. OBJECTIVE: To evaluate the association between FcepsilonRI-mediated histamine release from basophils and four bi-allelic single nucleotide polymorphisms of the FcepsilonRI-beta gene. METHODS: Phenotypes of asthma, such as maximal histamine release from basophils and atopy, were measured from 80 randomly recruited asthmatic children. Polymorphisms of the FcepsilonRI-beta gene were determined by PCR-based methods. RESULTS: The polymorphism in exon 7, resulting in Glu to Gly substitution, was significantly associated with histamine release from basophils to anti-IgE stimuli, but not with total IgE levels and skin test responses to aeroallergens. CONCLUSION: This study supports a role for the FcepsilonRI-beta gene in the expression of high affinity IgE receptor-mediated histamine release from basophils.     

Affinity of IgE antibody to antigen influences allergen-induced histamine release.

BACKGROUND: Although affinity of an antibody for an antigen is recognized to be an important factor in determining its biological effects, little is known about the relevance of such affinity of IgE antibodies to the functional response. OBJECTIVES: To investigate the effect of IgE antibody affinity to Der p 2 on Der p 2-induced histamine release from human basophils. METHODS: The most probable value of the dissociation constant (Kd) of IgE antibody to Der p 2 was calculated and histamine release by Der p 2-challenged leucocytes was used to evaluate the biological efficacy of the IgE antibody. RESULTS: The most probable Kd value of IgE antibody to Der p 2 ranged from 5.6 to 177.8 pM in 14 asthmatic patients sensitive to Der p 2. A significant correlation was observed in Der p 2-induced histamine release between the sensitivity and the Kd value for Der p 2-specific IgE antibody (rs = 0.797, P = 0.0040), suggesting that the higher the affinity, the lower the amount of allergen required for the release of a specific level of histamine. CONCLUSION: Apart from the changes associated with the reactivity, the sensitivity of histamine release is closely related to the affinity of IgE antibody for its antigen.     

Basophil histamine release in insect venom allergy

The aim of the present study was to investigate venom-related and venom-non-related immunological reactions in patients stung by bee or wasp. Sixteen consecutive patients (7 with local and 9 with systemic reactions) were tested with skin tests, RAST and basophil histamine release (BHR) test immediately after the insect sting and 2, 4, and 16 weeks later. No test was useful immediately after the insect sting, the "anergic period". In agreement with earlier findings, the SPT was the only allergy test that showed statistically significant differences between patients with local and systemic reactions, although a great overlap was found. Release of histamine from basophils after incubation with anti-IgE also showed statistically significant differences between local and systemic reactions. Further studies are needed, especially measurement of BHR after incubation with anti-IgE before insect stings.     

Influence of bronchial allergen challenge on histamine release by human basophils

BACKGROUND: Basophils can be primed by cytokines such as interleukin (IL) -3, IL-5 or granulocyte macrophage-colony stimulating factor (GM-CSF). It has been described that the concentrations of these cytokines are enhanced at sites of allergic inflammation as well as systemic in allergic asthma. OBJECTIVE: To investigate the priming status of basophils as detected by thapsigargin-induced histamine release during bronchial allergen challenge. METHODS: Ten subjects allergic to house dust mite were challenged via an aerosol delivery system. Spontaneous leucocyte histamine release as well as histamine release induced by various stimuli was measured in vitro at several time points. In addition, lung function parameters, serum IL-5 and blood eosinophil counts were evaluated. RESULTS: We found no effect of bronchial allergen challenge upon spontaneous leucocyte histamine release, nor upon histamine release induced by anti-immunoglobulin (Ig) E, house dust mite extract, C5a, fMLP, IL-3, PMA+ thapsigargin or IL-3+ thapsigargin. However, the priming status of basophils as measured by thapsigargin-induced histamine release was enhanced at 24 h after bronchial allergen challenge. Analysis of the individual data showed a heterogeneous initial response (30 min, 6 h) followed by a predominant increase at 24 h after allergen challenge. This increase in the thapsigargin-induced histamine release correlated with the increase in serum IL-5 levels at 24 h after allergen challenge. CONCLUSION: The priming status of human basophils as measured by thapsigargin-induced histamine release is enhanced 24 h after allergen challenge.