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Notes: Background Asthma, together with, In some cases, anaphylaxis, was observed in seven subjects following ingestion of royal jelly, a secretion of honey bees which is used as a health tonic.Objective To determine if reactions were lgE-mediated and to identify ailergenic components of royal jelly.Methods Skin-prick tests, immunoassays for specific IgE antibodies and protein blotting studies using patients’ sera and anti-IgE second antibodies were employed. Results Immunoassays detected IgE antibodies to royal jelly proteins in sera of subjects who reacted to the substance. A total of 18 different IgE-binding components were detected on blots following electrophoretic separation of royal jelly under dissociating conditions. Examination of 63 sera from subjects allergic to bee venom showed that there is no direct relationship between IgE antibody reactivity to bee venom allergens and to royal jelly proteins although 38% of the sera reacted with a royal icily solid phase. IgE antibody reactivity to royal jelly proteins was also detected in 52% of 75 subjects with allergies to inhalant and/or food allergens. Antibody binding of blotted royal jelly proteins was most marked in the molecular weight region 25–55 kDa and one component of MW∼55 kDa was detected by all of the reactive sera from roya jelly-allergic and control allergic subjects.Conclusions Symptoms of asthma and anaphylaxis seen in subjects following ingestion of royal jelly were true IgE-mediated hypersensitivity reactions. The clinical significance of the antibodies found in the sera of control subjects is not known but they may arise in response to common inhalant allergens that show allergenic cross-reactivity with royal jelly.

Notes: Positive RAST (〉 5% radioactive uptakes) to wheat endosperm proteins were found in approximately one-quarter of subjects who had both a positive skin prick and RAST (〉 10% radioactive uptake) to ryegrass pollen proteins. Immunoblotting of proteins electrophoretically transferred to nitrocellulose membrane after SDS-PAGE of ryegrass pollen and wheat endosperm proteins confirmed the crossreactive properties of the sera identified by RAST testing. Immunoadsorption of serum IgE onto nitrocellulose membrane, to which ryegrass pollen or wheat endosperm proteins had been adsorbed, removed IgE from crossreactive sera reactive to both ryegrass pollen and wheat endosperm proteins. Elution of the adsorbed IgE from the nitrocellulose membrane after immunoadsorption and probing blotted strips of both ryegrass pollen and wheat endosperm proteins supported the results obtained from the immunoadsorption experiments. This data provides evidence that the crossreactivity of IgE antibodies in sera reacting with both ryegrass pollen and wheat endosperm proteins involves common or related determinants and has implications for the clinical management of these allergic subjects.

Notes: Jack-jumper ant venom proteins were etectrophoretically separated on SDS-polyacry-lamide gels, transferred to nitrocellulose and probed with sera from subjects who had experienced an allergic reaction after being bitten by a jack-jumper ant. Ant venom components that bound IgE antibodies were detected by addition of 125I-anti-human IgE followed by autoradiography. Of the 17 polypeptides resolved by electrophoresis only three, of molecular weights approximately 14 kD, 12 kD and 10 kD, bound IgE antibodies from the panel of 50 sera examined. There was a marked similarity in the binding patterns by individual sera with almost all of the sera recognizing the 14 kD and 12 kD components. IgE-binding profiles of separated ant venoms from ants collected in different regions of Australia appeared to be very similar if not identical. Identification of the ant allergens is a necessary prelude to the preparation of standardized venom sac extracts suitable for safe and effective diagnostic and therapeutic use.

Notes: An immunoassay was developed to detect IgE antibodies to the widely used antibacterial drug trimethoprim. Significant levels of trimethoprim-reactive IgE antibodies were found in the sera of two patients who had experienced life-threatening allergic reactions following administration of a combination of trimethoprim and sulphamethoxazole. No IgE antibodies reactive with sulphamethoxazole were found in the sera of either patient. Inhibition experiments revealed that a high degree of cross-reactivity occurs between the drug-reactive IgE antibodies and two structural analogues of trimethoprim. 6-hydroxy- and 6-chloroirimethoprim. These experiments also indicated that the combining sites of the trimethoprim-reactive IgE antibodies in the two sera were probably complementary to different parts of the trimethoprim molecule. The assay should supplement skin testing in determining the offending drug in patients with suspected allergic sensitivity to trimethoprim–sulphamethoxazole complex.

Notes: An allergic reaction, provoked by exposure to the blowfly Lucilia cuprina and shown to be IgE-mediated, occurred in a subject employed in an entomological research laboratory. The subject's serum, and sera from three other asthmatic patients with IgE antibodies to blowfly extracts, also reacted with extracts from the screw-worm fly (Chrysomya bezziana). Results suggested that antigens from the two species share immunological cross-reactivity. Cross-reactions also exist between the different developmental stages of both species. Allergic reactions to inhaled insect allergens may not be uncommon in the Australian community.

Notes: IgE-antibodies reactive with extracts of a number of different marine invertebrate-species were demonstrated in the serum of a laboratory worker who experienced an acute attack of asthma following occupational exposure to powdered marine-organisms. Histamine was liberated from the patient's blood following in vitro challenge with sponge extract. The desirability of knowing the atopic status of employees in certain occupations is stressed.

Notes: Background Skin tests and tests for IgE antibodies show that subjects are usually sensitive to a number of different pollens, frequently from taxonomically diverse species which are assumed to be allergenically non-crossreactive. This suggests that the presence of IgE antibody-reactivity to an individual pollen may not necessarily have resulted from contact with that pollen or even with a taxonomically closely related species.Objective Since this has important consequences for allergen avoidance and desensitization of patients, we attempted to define allergenic relationships between diverse pollen species.Methods Sera from subjects were examined in direct IgE antibody binding experiments and by quantitative inhibition, protein blotting and adsorption and edition studies.Results Sera from subjects diagnosed as allergic to white cypress pine. Italian cypress. ryegrass or birch pollen were shown to have IgE antibodies that reacted with pollens from these four species and from cocksfoot, couch grass, lamb's quarter, wall pellitory. olive, plantain and ragweed. These reactions were confirmed in protein blotting and adsorption and elution studies where numerous IgE-binding bands were detected in all 11 different pollen extracts with sera from each of the different allergic categories, further evidence of allergenic (i.e. IgE-binding crossreactivity between the different pollens was provided by inhibition studies in which clear-cut inhibitions of IgE binding to the different pollen allergen discs were obtained with comparable amounts of the different pollen extracts.Conclusion We conclude that the presence of pollen reactive IgE antibodies may not necessarily be a true reflection of sensitizing pollen species.

Notes: Sera from 35 individuals with suspected allergies to inhaled flour were screened for the presence of immunoglobulin E (IgE) specific for wheat-flour proteins. Sera from nine asthmatic bakers with high wheat RAST scores were selected for further study with the aim of purifying the allergen(s) involved in bakers’ asthma and related conditions. However, each of the different techniques applied–ion exchange chromatography, preparative isoelectric focusing and the electrophoretic transfer, or‘Western blotting’ technique, showed that serum IgE from different individuals have markedly different specificities and bind to numerous wheat proteins. When three purified wheat proteins were tested–wheat germ agglutinin; a fraction purified using a concanavalin-A affinity column and a putative trypsin inhibitor–all were identified as allergens for some but not all of the allergic bakers.

Notes: Background An appreciation of the structural heterogeneity of allergenic determinants on penicillins and cephalosporins reveals the importance of side-chain groups and their involvement in many allergies to β-lactam drugs. Although allergenic cross-reactions between penicillins and cephalosporins are known to occur, the precise molecular bases of such recognitions and cross-sensitivities have rarely been studied and identified.Objectives The unexpected finding of a high incidence of positive IgE antibody reactions with both benzylpenicillin and cephalothin prompted serological and immunochemical studies to identify the chemical basis of antibody recognition of these drugs from the two different families of β-lactam antibiotics.Methods Adsorption studies were employed to identify whether or not a single population of antibodies was involved in the recognition of benzylpenicillin and cephalothin. Identification of the fine structural features recognized by IgE antibodies was investigated by quantitative hapten inhibition studies employing carefully selected β-lactam drugs, analogues and some other structurally related chemicals.Results Adsorption studies with penicilloic acid-solid phase clearly established that a single population of cross-reacting antibodies recognized both benzylpenicillin and cephalothin. Quantitative inhibition findings, especially with phenylacetic acid and 2-thiopheneacetic acid and with cephaloridine and cefoxitin, which have the same (2-thienyl)methyl side-chain as cephalothin, implicated the methylene group as the focus of the allergenic determinant recognized on benzylpenicillin and cephalothin. In addition to the methylene group, recognition graded into neighbouring structures including the amide group and extended weakly to the β-lactam ring.Conclusions Results confirmed that structural features as small as a methylene group may be allergenically important. In the present case, this group, making up only part of the different side-chains on benzylpenicillin and cephalothin, together with neighbouring structures extending toward the β-lactam ring, accounted for the cross-reactivity seen between structures that, at first sight, appear to be not closely related. Such subtle, small, common structural features are likely to be immunologically recognized and implicated in allergic reactions to other drugs, including β-lactam antibiotics.