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Flow-cytometric analysis of human basophil degranulation. III. Degranulation induced by allergens and antibodies in hay fever and bee venom allergic patients.

Human basophil degranulation responses to grass pollen and whole bee venom as allergens and to anti-IgE and anti-IgG4 as antibodies in hay fever and bee venom allergic patients were assessed using a flow-cytometric system. The concordance of basophil degranulation with skin tests and RAST assays reached more than 90%. These allergens and antibodies could degranulate basophils in a dose-dependent manner; however, there was a wide variation in the response of basophils obtained from different individuals. Moreover, a significant correlation was observed between the degree of degranulation by allergens and anti-IgE, or by allergens and anti-IgG4, but this was not the case between serum IgE concentrations and basophil response to anti-IgE. These data suggest that 'releasability' of basophils upon challenge by allergens and antibodies is also an important parameter in determining the degree of hypersensitivity in each subject.

Allergens↗

Optimization and characterization of freeze-dried multilamellar liposomes incorporating different standardized allergen extracts.

Desensitization therapy for type I allergy is now current practice. Liposomes have been proposed as a support for allergens to improve safety and effectiveness. The aim of this work was to optimize liposomal formulations of three different standardized allergen extracts and to test their allergenicity in vitro and in a preclinical trial. Allergen extracts (Dactylis glomerata, Dermatophagoides pteronyssinus, and cat hair and dander) were associated with multilamellar liposomes of varying compositions at different pH. Liposome-bound allergens were quantified by RAST inhibition after ultracentrifugation, and analyzed qualitatively by SDS-PAGE followed by immunoblotting. Their allergenicity was assessed by basophil degranulation in vitro, as compared with the allergenicity of an aqueous extract, and by skin tests in allergic subjects. The best association, about 50% of the added allergen, was obtained with negatively charged liposomes, when the pH of the allergen solution was adjusted so as to impart a net positive charge to the proteins. One-third of the liposome-associated allergens was located on the surface of the liposomes and was free to interact with antibody, as shown by RAST inhibition assays and the basophil degranulation test; the remaining two-thirds was encapsulated within the liposomes. All the major immunoreactive proteins in the extract were included. These liposomes could be readily freeze-dried and reconstituted without changing their properties. This study reveals the allergenic characteristics of liposomes and suggests their potential use in the treatment of allergic patients.

Allergens↗

Flow cytometry versus histamine release analysis of in vitro basophil degranulation in allergy to Hymenoptera venom.

BACKGROUND: Flow cytometry (FCM) has been proposed for specific allergy in vitro testing. We investigated its biological significance for allergy to Hymenoptera venoms and compared it with the routinely performed basophil histamine release test (HRT). METHODS: Blood samples from 26 allergic and 8 nonallergic donors were incubated with venom at serial concentrations. Basophils were analyzed with anti-CD45-PE-Cyanin 5, Anti-IgE-FITC, and Anti-CD63-Phycoerythrine. HRT was measured by radioimmunoassay. RESULTS: FCM was as convenient as HRT for measuring basophil reactivity in at least 87% of allergic and 75% of nonallergic subjects. CD63 outer expression was specifically induced in 91% of releaser subjects (86% on HRT) and in 1 of 10 tests in nonallergic donors, or one of six tests (16% on HRT) in allergic patients tested with an irrelevant allergen. Both methods were concordant in 85.7% of the tests. The three discordant patients had low-grade reactions and borderline biological responses on FCM (n = 2) or HRT (n = 1). CONCLUSIONS: The dynamic, physiologic significance of CD63, the dose-response curve, and dependency on ethylene-diaminetetra acetic acid suggested that both tests reflect the same mechanism.

Adolescent↗

[Leukocyte migration inhibitory factor and basophil degranulation in drug reactions].

We performed a prospective study in patients with a medical history of adverse reaction to drugs with the purpose of rule out allergy. We included 31 patients who were attended in the Allergy Service. We compared the sensibility and specificity of the test of inhibition factor of leucocytes migration and degranulation basophil against the exposition. After the statistical analysis, we concluded: the laboratory test, we have already mentioned, have little sensibility and specificity so the exposition test in the quickest, useful, and more simple method to determine drugs allergy, but more dangerous.

Adolescent↗

[Various methods for the diagnosis of allergy in pediatrics. Some correlations between different tests].

We studied the correlations between the different methods of diagnosis of the immediate allergy, IgE-dependent, in two current cases of pediatric allergology. In the mites allergy, the best correlation is observed between the skin tests (IDR) and the Rast. During the food allergy, first we found the best correlations between the prick-tests (PT) and the oral challenge (TPO), then between the prick-tests and the Rast. In these two studies, we got no further element to the diagnosis from the direct test of human basophil degranulation (TDBH).

Adolescent↗

Basophil degranulation induced by oral poison ivy antigen.

Seven subjects shown by patch test to be sensitive to poison ivy oleoresin were challenged with graded oral doses of ivy extract. In each instance the circulating basophil leukocytes showed significant degranulation within one hour of challenge. This finding was interpreted as evidence of the presence of immediate-type circulating antibody to ivy antigen in these subjects. No drop in the absolute basophil count was noted, but with higher oral doses the degranulation persisted for several days. Thirteen control subjects showed no change in the basophil morphology or count, indicating that the resin at these levels was not toxic to this cell. All but one of the sensitive subjects showed objective patch test evidence of hyposensitization following the intensive three-week course of oral poison ivy antigen.

Antigens↗

Immunologic studies of anaphylaxis to iron dextran in patients on renal dialysis.

Systemic reactions resembling anaphylaxis have occurred after intravenous (IV) iron-dextran administration, a treatment modality that has acquired increased acceptance following the use of erythropoietin for the anemia of patients with chronic renal diseases. Three such patients sustained anaphylactoid reactions immediately after receiving IV test doses of iron-dextran which were their only known exposures. In an effort to determine the mechanism of their reactions, we applied tests for (1) basophil degranulation by iron-dextran, basophil histamine release; (2) a type I anaphylactic reaction, specific IgE antibodies; and (3) an immune complex activation, specific IgG antibodies against iron-dextran. Six other patients with renal diseases served as controls, three of whom had tolerated IV iron-dextran, and three without known exposure. One patient only had any test abnormalities. Her initial positive basophil histamine release and specific IgG antibodies reversed and declined respectively at a 4-month follow-up study. She had developed anaphylaxis, and her studies had been performed at a time after anaphylaxis earlier than the other two. The mechanisms of iron-dextran anaphylaxis may be multiple and not be detectable several months after the incident. Prospective studies will probably be required for a predictive test to be developed.

Adult↗

Enzyme release and superoxide anion production by human alveolar macrophages stimulated with immunoglobulin E.

Human alveolar macrophages specifically released lysosomal beta-glucuronidase and neutral proteases when successively incubated with IgE, and then, for 30 min, with anti-IgE. Superoxide anion O2- generation was obtained when anti-IgE-opsonized zymosan was added to IgE-incubated cells. Macrophages from smokers excreted twice as much enzymes and superoxide as cells from non-smokers. It was possible to induce the specific release of beta-glucuronidase with normal alveolar macrophages successively incubated with the serum of patients allergic to house dust or to grass pollen and then with the specific allergen. This characteristic opens the field to a direct test for allergic sera by analogy with the allergen-induced degranulation test of sensitized basophils.

Allergens↗

Degranulation of basophilic leukocytes in allergic contact dermatitis reactions in man.

Basophilic leukocytes participating in allergic contact dermatitis in man underwent progressive degranulation over the course of several days after skin test. Less than 10% of basophils were degranulated in 24-hr reactions, but more than 60% were degranulated by 72hr. In electron microscopic individual basophil granules developed looser packing of particles by finely granular material, and eventual loss of all visible granule contents, changes that were progressive between 2- and 3-day reactions.

Adolescent↗

Purification and immunoglobulin E-binding properties of peanut allergen Ara h 6: evidence for cross-reactivity with Ara h 2.

BACKGROUND: IgE-binding peanut proteins smaller than 15 kDa were previously identified as potential allergens in the majority of our peanut allergic population. OBJECTIVE: To characterize the novel allergen in order to determine whether it was similar to one of the thus far identified recombinant peanut allergens (Ara h 1-7). METHODS: An IgE-binding protein of <15 kDa was purified and identified via N-terminal sequencing. Its IgE-binding properties were investigated using immunoblotting, basophil degranulation, and skin prick testing. Possible cross-reacting epitopes with other peanut allergens were studied using IgE-immunoblotting inhibition. RESULTS: The purified protein is a monomeric protein with a molecular weight of 14,981 Da as determined using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectroscopy. The amino acid sequence of the first 39 N-terminal residues is identical to that of Ara h 6, indicating that the allergen is Ara h 6. It is recognized by 20 out of 29 peanut-allergic patients on IgE-immunoblot, and its potent biological functionality is demonstrated by the degranulation of basophils, even at concentrations below 10 pg/mL, and by positive skin prick reactions. Ara h 6 has homology to Ara h 2, especially in the middle part and at the C-terminal part of the protein. Almost complete inhibition of IgE-Ara h 6 interaction with Ara h 2 demonstrates that at least part of the epitopes of Ara h 6 are cross-reactive with epitopes on Ara h 2. CONCLUSIONS: Peanut-derived Ara h 6 is a biologically active allergen recognized by the majority of our peanut-allergic patient population and can be considered a clinically relevant peanut allergen.

2S Albumins, Plant↗

[Critical study of methods for the diagnosis of allergic asthma].

A search for an allergic cause in asthma is fundamental to the diagnosis. Typically it is based on: A clinical history. Specific cutaneous and inhaled provocation tests which can produce a possible reaction (early and delayed) which are of great pathophysiological and therapeutic interest. In vitro tests (which enable the different phases of the allergic reaction to be distinguished) to know the serum IgE antibody levels (total IgE, specific IgE and their fixation to cell receptors) cell tests on the degranulation of basophils and the dosage of chemical mediators: histamine, leukotrienes, prostaglandins, P.A.F. in the serum or in the bronchial alveolar lavage liquid, from the study of cells or tissue samples. In this regard the authors stress two recent techniques enabling direct access to bronchial tissue and the pulmonary parenchyma, which are bronchoalveolar lavage and bronchial biopsy, both are possible today by using a fibroscope. The broncho-alveolar lavage still remains in the research area, and is not always well tolerated in asthmatics. It already allows a better definition of the major allergic cytological and biochemical components in asthma (IgE, IgA, albumin, phospholipids, mast cells and eosinophils). Bronchial biopsies with ultra-structural studies, and above all immunopathology (by immunofluorescent techniques and peroxidase stains) enable groups of asthmatics to be uncovered who were considered as non-allergic by the unsuspected intervention of hypersensitivity mechanisms to IgE (the presence of cells carrying IgE); these biopsies enable the importance of inflammatory factors to be confirmed and equally to establish the prognosis in certain asthmatics by the degree of irreversibility of the lesions (fibronectin).(ABSTRACT TRUNCATED AT 250 WORDS)

Asthma↗

A single centrifugation step method for the simultaneous separation of different leukocytes with special reference to basophilic leukocytes.

A simple method of separating mononuclear leukocytes, basophils, neutrophils and an eosinophil fraction from human blood is described, using discontinuous Percoll gradient centrifugation. Mononuclear cells were found in the upper layer (band 1) at a density of less than or equal to 1.072. The second band with a density of less than or equal to 1.082 contained most of the basophilic leukocytes (av. 70% and 8-20% of the differential cell count) and a minor part of the mononuclear cells (av. 8%). In the third band, density less than or equal to 1.1, 82-91% of the polymorphonuclear cells (PMN) were found, consisting mainly of neutrophils. 35-70% of the eosinophilic PMN cells are located in band four (density greater than 1.1). The function of the basophil-enriched fraction was tested by degranulation with specific antigen.

Basophils↗

A major allergen gene-fusion protein for potential usage in allergen-specific immunotherapy.

BACKGROUND: Specific immunotherapy is a common treatment of allergic diseases and could potentially be applied to other immunologic disorders. Despite its use in clinical practice, more defined and safer allergy vaccine preparations are required. Differences between epitopes of IgE that recognize the 3-dimensional structure of allergens and T cells that recognize linear amino acid sequences provide a suitable tool for novel vaccine development for specific immunotherapy. OBJECTIVE: The aim of the study was to delete B-cell epitopes and prevent IgE crosslinking, but to preserve T-cell epitopes by fusion of 2 major allergens of bee venom because of a change in the conformation. METHODS: By genetic engineering, we produced a fusion protein composed of the 2 major bee venom allergens: phospholipase A 2 (Api m 1) and hyaluronidase (Api m 2). RESULTS: The Api m [1/2] fusion protein induced T-cell proliferation and both T H 1-type and T H 2-type cytokine responses. In contrast, IgE reactivity was abolished, and profoundly reduced basophil degranulation and type 1 skin test reactivity was observed. Pretreatment of mice with Api m [1/2] fusion protein significantly suppressed the development of specific IgE as well as other antibody isotypes after immunization with the native allergen. CONCLUSION: The novel fusion protein of 2 major allergens bypasses IgE binding and mast cell/basophil IgE FcepsilonRI crosslinking and protects from IgE development.

Adult↗

[Neurological manifestations of tuberculosis].

One hundred and forty-four new cases of pulmonary tuberculosis were examined. The examination revealed the following neurological syndromes: vegetovascular dystonia, disseminated cerebral microsymptoms, focal lesion of the brain, sensory polyneuropathy. The presence of positive specific basophilic degranulation reactions and intracutaneous tuberculin test suggests that the body shows allergic reactions in response to Mycobacteria tuberculosis. And since connective tissue that presents in the vessels and tunics in the nervous system is involved into a pathological process in allergy, neurological disorders are always secondary in tuberculosis and due to the primary vascular wall lesion that following the type of secondary allergic vasculitis.

Adult↗

An attempt to prevent anaphylaxis by aerosolized antigen in guinea pigs.

In an attempt to provide an alternative and safer technique of specific hyposensitization for those patients for whom the conventional treatment presents a high risk for anaphylaxis, we used a guinea pig model for extracorporeal hyposensitization. We sensitized three groups of guinea pigs with an olive pollen extract. Two of the groups were sensitized before removal of their buffy coat and the third group was sensitized after the removal of their buffy coat. The buffy coat cells were incubated with the same antigen and intracardially reinjected into their respective donors. Subsequent challenges by aerosolized antigen and intracardiac injections were performed. We did a basophil degranulation on random samples of buffy coat of tested and control animals. We skin tested the animals and we examined the histopathology of their lungs. The animals reinjected with the incubated buffy coat prior to sensitization showed a greater protection from aerosolized antigen and the onset of their anaphylactic symptoms was significantly delayed when compared with controls. The results of basophil degranulation studies showed that animals sensitized before removal of their buffy coat had approximately a threefold increase of degranulated basophils as compared with animals that were sensitized after removal of buffy coat and approximately a fourfold increase when compared with controls. This degranulation did not affect the specific skin test. Histopathologic observations did not reveal any characteristics typical of anaphylaxis.

Aerosols↗

Recent advances in the understanding of the penicillin urticarias.

The three major groups of immunoglobulins (gamma G, gamma A, and gamma M) associated with this disease are reviewed. The presence or absence of atopic disease may account for percentage variability of gamma A because reagins (skin-sensitizing antibodies) are found in this immunoglobulin. The gamma A is the antibody usually responsible for anaphylaxis, rather than the gamma G precipitins, so stressed in the past. All three immunoglobulins may be found in serum sickness, which could account for the complex nature of this type of penicillin urticaria. The merits of the immunological tests (penicilloyl-polylysine, benzyl penicillin, hemagglutination, basophil degranulation) for the detection of penicillin sensitivity are analyzed, particularly as each applies to the various types of penicillin urticaria (serum sickness, anaphylactic, dermographic, delayed dermographic, and simple chronic urticaria and the lupus diathesis). The penicilloyl-polylysine test is greatly overrated as a means of predicting possible anaphylaxis. The benzyl penicillin skin test properly performed is an excellent means of indicating this.

Humans↗