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Dog serum albumin as an allergen. IgE, IgG and lymphocyte responses in dog dander-sensitive asthmatic children.

To study the allergenicity of dog serum albumin (DSA) in dog-sensitive subjects, we investigated 203 asthmatic children by means of the skin prick test (SPT), the radioallergosorbent test (RAST) and the in vitro lymphocyte stimulation test. Significant SPT reactions to DSA were observed in only 9 out of 80 subjects with a significantly positive SPT reaction to dog dander and hair (DDH). Analogously, positive DSA RAST results were observed only in a minority of the cases with a positive DDH RAST. Significant SPT reactions to DSA were not observed in subjects with a negative clinical history of dog allergy, or in subjects with a negative reaction to DDH in the SPT or in the provocation test. DSA induced remarkable lymphocyte stimulation in only 1 subject, who also had a significant SPT reaction to DSA. DSA-specific serum IgG antibody titers measured by ELISA were not found to correlate with DSA SPT or DSA RAST.

Adolescent↗

Urticaria from allergy to a purified human anti-Rh antibody preparation.

This case presentation describes a young woman who developed generalized urticaria after receiving the human anti-RhD(D) preparation, WinRho, intravenously. Allergy skin tests and the radioallergosorbent test (RAST) for IgE antibodies to the human anti-D immunoglobulin preparation were positive. Further studies using high-pressure liquid chromatography and protein A column chromatography implicated a nonimmunoglobulin low-molecular-weight contaminant. This case report illustrates an allergic reaction to a highly purified human immunoglobulin preparation, and demonstrates approaches to assessment of such a reaction.

Adult↗

[The basophil degranulation test in the diagnosis of bee and wasp sting allergies].

Comparison of basophil degranulation test (BDT) with radioallergosorbent test (RAST) in 50 patients with anamnestically certain or probable hymenoptera allergy yielded practically equal results. In patients who had experienced their allergic reaction a long time ago, BDT seemed to react positively over a longer period of time than RAST. As BDT is technically easy to perform and moderate in price, it is suited to substitute RAST.

Adolescent↗

A new, purified Dermatophagoides farinae allergen preparation. Evaluation with SPT and RAST techniques.

A purified, standardized and characterized allergen preparation of the house dust mite Dermatophagoides farinae (Df) was evaluated by skin prick test (SPT) and radioallergosorbent test (RAST) in 88 subjects. Skin reactions to the purified Df preparation and a corresponding crude Df preparation were compared. SPT was also performed with a crude Dermatophagoides pteronyssinus (Dpt) preparation to compare reactions obtained with the two mite preparations. By SPT the purified Df allergen preparation was representative of the crude Df preparation (r = 0.78) and the correlation between skin reactions to Df and Dpt was high (r = 0.78). The concordance between results obtained with RAST and SPT techniques with the purified Df preparation was high (84%). The purified D. farinae preparation was well tolerated and is well suited for SPT.

Allergens↗

Comparison between two different assays for measurements of allergen-specific IgE and skin prick test in the diagnosis of insect venom allergy.

Forty-one patients stung by wasp and 29 by bee were evaluated by comparing the correlation between skin prick test (SPT), Phadebas radioallergosorbent test (P-RAST) and Magic Lite SQ Specific IgE assay (LIA). All patients had had a systemic reaction to insect sting. In the patients stung by bee we found agreement between SPT and P-RAST, and SPT and LIA. Similarly, there were no significant differences in sensitivity between P-RAST and LIA (p > 0.05). In patients stung by wasp, SPT was found to be more sensitive than P-RAST. There were no differences between SPT and LIA or between P-RAST and LIA.

Allergens↗

IgE antibody response against Aspergillus umbrosus in farmer's lung disease.

IgG and IgA antibodies against fungus Aspergillus umbrosus have been found in the sera of patients with farmer's lung (FL) disease and healthy exposed farmers in Finland. To determine the IgE response to antigens of A. umbrosus and Candida albicans, sera from 20 patients with FL, 20 healthy farmers and 20 nonfarming controls were tested by nitrocellulose radioallergosorbent test (RAST). The values of RAST indices were low in each group and the only statistically significant difference was found between the groups of FL patients and nonfarming controls against A. umbrosus polysaccharide antigen. Individual IgE responses to polysaccharide antigens of A. umbrosus and C. albicans correlated among FL patients, however, no cross-reacting IgE antibodies could be shown. To conclude, the IgE antibody levels of A. umbrosus polysaccharide and crude antigens were low in FL patients, healthy exposed farmers and nonfarming controls. Neither polysaccharide nor crude antigen-specific IgE antibodies of A. umbrosus have any diagnostic value in FL disease.

Antibodies, Fungal↗

In vitro lymphocyte proliferation in the diagnosis of allergy to phenoxymethylpenicillin.

BACKGROUND: The aim of this study was to investigate in vitro lymphocyte proliferation in the diagnosis of allergy to phenoxymethylpenicillin (PcV), comparing chemically reactive PcV, added to cell cultures in unconjugated form, to a PcV-PLL (poly-L-lysine) conjugate as antigens. Side-chain specificity of lymphoproliferative responses was investigated with reactive benzylpenicillin (PcG) and bacampicillin. METHODS: Seventeen patients with a history of hypersensitivity reactions in connection with PcV treatment were studied by means of the lymphocyte transformation test (LTT), the radioallergosorbent test (RAST), skin tests (prick and intracutaneous), and oral challenge with PcV. LTT was also performed in 20 control subjects exposed to PcV therapeutically, and in eight subjects with occupational exposure to this penicillin. RESULTS: Nine patients had a positive in vivo test to PcV (five by oral challenge, three by intracutaneous test, and one by both tests), and six were challenge-negative. When reactive PcV was used as antigen in LTT, positive LTT responses were observed in five of the nine patients with a positive in vivo test, and two of them were also side-chain specific. Positive LTT responses with reactive PcV also correlated with a positive RAST in five of seven subjects. None of the six patients with a negative challenge test, and only one of the 28 controls showed a positive LTT result with reactive PcV. Thus, the specificity of LTT with reactive PcV was 96%. In contrast, when PLL-conjugated PcV served as antigen, four challenge-negative subjects and 11 controls were LTT-positive. CONCLUSIONS: The results of this study indicate that LTT with chemically reactive PcV could be useful as an in vitro complement in the diagnosis of PcV allergy and as a tool to reveal the side-chain specificity of peripheral blood lymphocytes. A positive LTT to PLL-conjugated PcV may be an indicator of immunization, but not necessarily allergy, to the penicilloyl structure.

Administration, Oral↗

A comparison of two RAST methods and skin prick testing in the diagnosis of wasp venom allergy.

With the aim of evaluating the correlation between skin prick test and two radioallergosorbent tests (RAST) using paper (P-RAST) and Al(OH)3 (Al-RAST) as sorbent materials, 45 consecutive patients known to have been stung by wasp within 6 months were examined. Four patients had a normal reaction, four a large local reaction and 37 a systemic reaction. We found a good correlation between a systemic reaction and a positive P-RAST. Fifty-one per cent of patients with a systemic reaction had a negative Al-RAST, whereas only 8% had a negative P-RAST. Eight per cent of patients with a systemic reaction had a negative SPT. In the eight patients without a systemic reaction, the same patient reacted positively in Al-RAST and P-RAST.

Adolescent↗

Sensitization to nonvenom contaminants in a venom preparation.

An individual is described who appeared to be sensitive to nonvenom contaminants in a venom preparation. His IgE antibodies, measured by the immediate direct skin test and the radioallergosorbent test (RAST), reacted with a yellow jacket venom preparation obtained by "washing" of venom sacs. With yellow jacket venom obtained by electriral stimulation, there was a skin test reaction of equivocal significance and no serum antibodies were detected by the RAST. Moderate reactions were also found with yellow jacket body extracts. In contrast, sera obtained from patients with yellow jacket sting anaphylaxis showed strong reactions with the electrically stimulated venom preparation and only a few reacted with the body extract. In additional studies, the patient's serum reacted with yellow jacket extracts devoid of venom and a variety of hornet and wasp extracts. Analyses of the two yellow jacket venoms by gel diffusion using rabbit antisera showed the presence of body proteins in the venom obtained by venom sac "washing." Subsequent history revealed the presence of insect nests in the roof of the patient's bedroom, perhaps the source of inhalant exposure and sensitivity. This case history demonstrates the need for venom extracts that do not contain potentially sensitizing extraneous material.

Adolescent↗

Diagnosis and immunotherapy of mould allergy. I. Screening for mould allergy.

In order to screen for mould allergy, extracts of five common atmospheric moulds (Cladosporium, Alternaria, Penicillium, Aspergillus and Mucor) from various manufacturers were investigated in 130 patients (5-60 years old) with clinical symptoms indicating possible mould allergy. The patients were screened by skin prick test (SPT) and radioallergosorbent test (RAST). SPT seemed to be more sensitive than RAST as a diagnostic screening procedure (80% positive reactions to one or more species compared to 50%). With a partially purified, standardized preparation of Cladosporium herbarum more positive reactions were obtained than with crude extracts without evidence of any unspecific reactions. The difference between commercial and standardized extracts is most probably a result of a variation of both the biological potency of allergenic determinants and the allergenic composition. A considerable number of negative RAST reactions with standard discs were found in patients with positive skin reactions to partially purified Cladosporium, but RAST seemed to be more sensitive than SPT with the other commercial mould extracts. Based on the screening, a very convincing tendency to IgE-reactivity to other moulds was found in patients reacting to Cladosporium, the most common cause of mould allergy. The results confirm the inadequacy of most mould extracts used in diagnostic procedures and strengthen the value of using standardized extracts.

Adolescent↗

Meat allergy: II--Effects of food processing and enzymatic digestion on the allergenicity of bovine and ovine meats.

OBJECTIVES: This study was designed to evaluate whether peptic treatment of BSA and OSA affects their allergenicity and to evaluate the effect of technological treatments of meat for infant feeding on the allergenicity of these proteins. SUBJECTS: Twelve children (8 males and 14 females) suffering from atopic dermatitis (AD), aged 12 months to 4.33 years (mean age 2.21 +/- 1.05 years). STUDY DESIGN AND METHODS: Children suffering from atopic dermatitis (AD), (AD), clinically reactive and SPT-positive to beef, underwent skin prick testing (SPT) and radioallergosorbent test (RAST) with BSA and OSA, before and after peptic treatment. They were tested also with commercially available homogenized bovine meat (HBM) and with freeze-dried bovine (FDBM) and ovine (FDOM) meats. Peptic digestion of BSA and OSA was carried out in a Dubnoff's water bath containing 0.05 mg/ml of pepsin. SPT and RAST were performed for 1 mg/ml of BSA and OSA digested 5 minutes, 2 hours and 4 hours with pepsin; homogenized bovine meat, and FDBM and FDOM. SPT results were expressed as diameters (in mm) of the wheal obtained after SPT; a diameter > or = 3 mm was considered as positive. RAST was considered positive for IgE values 5 > UI/ml. RESULTS: SPT to native BSA and OSA were positive in all patients. Only 2 of the 12 children were SPT-positive to HBM, FDBM, and FDOM. After digestion, SPTs and were positive as follows: for BSA, 4/12 after 5 minutes peptic treatment, 2/12 after 2 hours and 2/12 after 4 hours; for OSA, 3/12 after 5 minutes peptic treatment, none after 2 and 4 hours. None of RASTs was positive after peptic attack. CONCLUSIONS: Both proteolytic digestion and technological treatment reduced the allergenic potential of meat products.

Animals↗

Alternative G1m, G2m and G3m allotypes of IGHG genes correlate with atopic and nonatopic pathways of immune regulation in children with bronchial asthma.

Most genetic studies of bronchial asthma deal with IgE responsiveness. The manner by which allergens trigger IgE production and activate mast cells suggests that several genetic loci may be involved. Several reports of candidate genes include chromosome 6 and HLA antigens, chromosome 14q11 and the alpha chain of the T cell receptor, chromosome 11q32 and the beta chain of the high-affinity IgE receptor and chromosome 5 and the gene cluster for IL-4, respectively. In addition, the immunoglobulin heavy chain G (IGHG) genes on chromosome 14q32 have been associated with both atopic and non atopic bronchial asthma in children. In order to further investigate the role of IGHG genes in asthmatic children, the phenotypes of patients with homozygous but alternative IGHG genes were investigated. IGHG gene expression of patients with childhood asthma was determined by serum Gm allotypes with a quantitative competitive indirect ELISA method. The groups consisted of 24 children with the homozygous G3m(b/b)-G1m(f/f)-G2m(n/n) and 16 with the alternative G3m(g/g)-G1m(a/a)-G2m(-n/-n) genes. The two different genotypes were investigated for serum IgE (PRIST), serum IgG subclass levels (radial immunodiffusion), Gm allotype levels (competitive ELISA), IgA and IgM levels (radial immunodiffusion), peripheral blood eosinophils, specific IgE antibodies (skin prick test, SPT, or radioallergosorbent test, RAST), number of peripheral blood CD lymphocyte markers (flow cytometry) and serum IL-4 and IFN-gamma levels (ELISA). Comparison of the two genotypes in children with bronchial asthma revealed significantly increased IgE (p < 0.001), increased specific IgE (p < 0.001), as investigated by SPT or RAST (n = 10 allergens tested), increased number of peripheral blood eosinophils (p < 0.01), increased serum IgG1(f/f)(p < 0.001), IgG2(n/n) (p < 0.001) and IgG3(b/b)(p < 0.01) levels, and decreased CD8 given in percent of the total number of peripheral lymphocytes, (p < 0.02) in the G3m(b/b)-G1m(f/f)-G2m(n/n) genotype. The asthmatic children with the G3m(g/g)-G1m(a/a)-G2m(-n/-n) genes instead showed low IgE levels, practically no specific IgE antibodies, a lower number of peripheral blood eosinophils, lower IgG1(a/a), IgG2(-n/-n) and IgG3(g/g) serum levels and higher CD8 lymphocyte numbers. The results show that the IGHG3(b/b)-IGHG1(f/f)-IGHG2(n/n) genes are in linkage disequilibrium with allergen-specific high-responding IGHE genes and present the atopic phenotype of bronchial asthma, while the IGHG3(g/g)-IGHG1(a/a)-IGHG2(-n/-n) genes present the nonatopic phenotype of childhood asthma. The two genotypes with different amino acid epitopes of their constant heavy gamma1, gamma2 and gamma3 chains presented qualitatively different IgG1, IgG2 and IgG3 molecules, respectively, and also different serum IgG1, IgG2 and IgG3 levels, together with different numbers of peripheral blood eosinophils and CD8 lymphocytes. The two IGHG genotypes represent different pathways of human immune regulation. An association of atopic IGHG genotype with other candidate genes for atopy could be suggested.

Adolescent↗

[Recurrent aphthous stomatitis: which role for viruses, food, and dental materials?].

Recurrent aphthous stomatitis is a frequently occurring disorder which may be a clinical feature of systemic disease. For many other patients, it is a tedious problem often having no known cause. The aim of this study was to verify if immune responses to common foods and/or viruses are involved in the etiopathogenesis of recurrent aphthous stomatitis. Sixteen patients with this disorder were studied by measurement of immunoglobulin classes (IgG, IgA, IgM), blood lymphocyte subpopulations, blood circulating immune complexes, and complement fractions (C3 and C4). Intradermal skin tests for common food and inhalant allergens were performed in all cases. In 5 patients with positive skin tests, serum specific IgE were tested for the same allergens by radioallergosorbent test. Skin patch tests for dental material were performed in all cases. Oral mucosal biopsies and/or cytology samples were taken in 10 cases for histopathological evaluation and in situ hybridization for Papillomavirus, Cytomegalovirus, Herpes simplex virus I and II, Epstein Barr virus. In 13 patients, lymphocyte subpopulations were altered, with a reduced CD4/CD8 ratio. No other alterations of serum immunological parameters were observed. Skin patch tests for dental material were negative in all cases, while skin tests for food allergens were positive in 5 cases (not confirmed by radioallergosorbent test or food challenge tests). Virus antigen and DNA were not found in mucosal specimens, although one patient was positive for Epstein Barr virus DNA by in situ hybridization. An alteration of the CD4/CD8 ratio was demonstrated in most of the patients with recurrent aphthous stomatitis, although immune responses to food and/or dental material and/or common viruses did not seem to be involved in the etiopathogenesis of this disorder.

Adult↗

Familial background of respiratory atopy. A factor of type I allergy to house dust mite in patients with atopic dermatitis.

Skin prick and radioallergosorbent tests with the house dust mite were performed in 120 patients with atopic dermatitis. The results showed that about 60% of the patients had type I allergy to the mite. Results of the prick and radioallergosorbent tests did not relate to the severity of skin involvement, nor to the seasonal fluctuation of the disease. Positive skin and radioallergosorbent tests occurred in many patients with atopic dermatitis who had a personal or family history of respiratory atopy. However, both of these tests were negative in the majority of patients with "pure" atopic dermatitis who had neither a personal nor a family history of respiratory atopy. It was suggested that a familial background of respiratory atopy is an important factor for the development of type I allergy to the house dust mite in patients with atopic dermatitis.

Adolescent↗

Allergy to penicillin: fable or fact?

OBJECTIVE: To assess whether, on the basis of one blood test, penicillin allergy might be excluded sufficiently for general practitioners to give oral penicillin to patients claiming a history of penicillin allergy. DESIGN: Prospective study of patients referred by general practitioners. SETTING: Outpatient allergy clinic in a district general hospital. PATIENTS: 175 referred patients who gave a history of immediate type reaction to penicillin, of whom 144 attended as requested and 132 completed the investigations. MAIN OUTCOME MEASURES: History and examination, serum radioallergosorbent test to phenoxymethylpenicillin and benzylpenicillin, and oral challenge with penicillin. RESULTS: Of 132 patients, four were confirmed to have penicillin allergy by the radioallergosorbent test and 128 had an oral penicillin challenge without ill effect. CONCLUSIONS: Most patients who gave a history of penicillin allergy are not so allergic, and their actual allergic state should be substantiated whenever feasible. For patients reporting minor or vague reactions negative findings with a radioallergosorbent test to phenoxymethylpenicillin and benzylpenicillin provide sufficient evidence to give oral penicillin safely.

Administration, Oral↗

Studies on Alternaria allergens. I. Isolation of allergens from Alternaria tenuis and Alternaria solani.

Extracts of Alternaria tenuis and Alternaria solani were separated into dialyzable (molecular weight less than 10,000) and non-dialyzable forms. The latter was further fractionated by gel filtration through Sephadex G-100 followed by ion-exchange chromatography on DEAE-cellulose. The dialyzable material was fractionated by gel filtration through Sephadex G-50. The allergenic activities of the fractions obtained from the A. tenuis extract was measured in vitro by the radioallergosorbent test assay and the allergenic potency was measured by radioallergosorbent test inhibition assay. Allergenic activity was detected in most of the non-dialyzable fractions, the majority of the activity being in the last G-100 fraction (MW approximately 20,000) which was predominantly protein in nature. The same component may be responsible for the activity found in the dialyzate and its first G-50 fraction since the immunodiffusion studies indicated that the last G-100 fraction has antigenic components in common with those of the first G-50 fraction. In addition, cross-reactions between A. tenuis and A. solani extracts show that the two species share common antigenic determinants.

Allergens↗

In vitro testing for immunoglobulin E-mediated food allergies.

The role of immunoglobulin E-mediated food allergy in subjects with allergic disorders, especially in patients with rhinitis and sinusitis, is underestimated by clinicians because of the initial attribution of these disorders to immediate-type hypersensitivity reactions. The difficulties of diagnosing food-related reactions have caused further delay in their recognition and incorporation into the daily practice of diagnosing food allergy. Two of the diagnostic methods for food allergy are the in vitro assay of total immunoglobulin E and the measurement of food-specific immunoglobulin E levels in serum with the radioallergosorbent test. Measurement of specific immunoglobulin E level is the most commonly used but also one of the most controversial techniques. We examined 123 patients with rhinitis who were referred to our otolaryngology/allergy clinic between January and April 1995. All patients received an initial radioallergosorbent test screen, which included milk. We determined the positive predictive value of this positive screen and, in particular, of a positive test for milk in the diagnosis of immunoglobulin E-mediated food allergies in these patients. Conclusions were based on comparison with the result of an additional radioallergosorbent test food panel consisting of eight common and two investigational food allergens.

Adolescent↗

Comparison of three variations of the radioallergosorbent test-inhibition assay for measuring allergenic activity of grass pollen extracts.

Three variations of the radioallergosorbent (RAST)-inhibition assay (RI) have been compared for measuring the allergenic activity of grass pollen extracts. The main difference between the three assays consisted in the solid supports to which the allergens were coupled. These supports were paper disks, microcrystalline cellulose, and Matrex. It could be demonstrated that all three variations of RI yielded almost identical results as expressed by their F value (F0). Correlations between the three methods were highly significant (P less than 0.001). Three independent valid assays showed an excellent reproducibility of each test system (P less than 0.01). Three different preparations of each of the supports yielded highly reproducible F0 (0.76 +/- 3% SD). Evaluation of the 50% inhibition values achieved with the different assays based on protein showed differences between the three supports. Provided the same allergen extract is coupled to the different solid supports and the results are related to a reference preparation, different laboratories using different forms of RI will be able to compare their results.

Allergens↗