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Mosquito allergy has been conceived as the cutaneous reactions that appears during and after mosquito biting process; a perception that is supported by several scientific research. Additional data have led to conceive that other manifestations of allergic responses may occur as a cause of the exposure to somatic mosquito allergens. Two main phenotypes of mosquito allergy are identifiable: the cutaneous allergic reactions, induced by salivary allergens, and other manifestations of the allergic responses such as asthma and allergic rhino conjunctivitis that are caused by somatic allergens. The cutaneous reactions have kept the focus of attention of the scientific community. It appears as skin lesions that resembles the phenotype of papular urticaria with a defined natural history of the disease. Although these two phenotypes of mosquito allergy seem to be well differentiated in terms of the allergens that are involved and the routes of exposures, other factors such as geographical distribution, may participate. Mosquitoes have adapted to the host immune response against bites, producing immunomodulatory molecules that counteract such defensive response. The role that the immunomodulatory molecules have on the allergic immune response has not been studied yet and it is still not known if affects all mosquito allergy phenotypes. Only a few studies of allergen specific immunotherapy for cutaneous allergic reactions induced by mosquito bites have been done, and none for respiratory allergic responses. The clinical practice focuses on symptom management and avoiding mosquito bites as much as possible. Avoiding mosquitoes, using different well described methods, is still the best option to limit contact with these insects. The lack of knowledge of mosquito allergy have raised several questions that affects the clinical management of this allergic disease, from its diagnosis, prevention and immunotherapy., Competing Interests: Conflict of Interest JFC is an employe at the company Inmunotek, S.L. EFC was an employe at the company Inmunotek. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Purpose of Review: The purpose of this review is to provide an update on the intriguing relationships between allergies, allergen immunotherapy, cancer, and immune disorders. Allergic diseases and cancer are increasing in incidence and prevalence and a potential relationship, or not, between these diseases have been suggested for many years., Recent Findings: Recent findings suggest that there may be some causative effects between certain types of cancer and allergic diseases, as described in the text. Some types of cancer may be more linked to the presence of an allergic disease, than others. However, epigenetic factors, such as tobacco smoke alcohol and toxic substances should also be taken into consideration., Summary: The association between allergy and cancer is complex and depends on the specific allergy and the specific organ under consideration. Regarding pancreatic cancer, colorectal cancer (CRC), and glioma, all types of allergies were shown to be a protective factor. Conversely, asthma is a risk factor for lung cancer as is atopic dermatitis for skin cancer. Despite extensive research, no definite relationship has been determined, and no clear relationship, either positive or negative, to allergies can be observed. These results should be corroborated with large epidemiological well designed prospective studies due to some weaknesses in the previous investigations., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Objectives: Several studies have described peach tree (PT) as an occupational allergen. The aim of this work was to assess the effect of Prunus persica 9 (Pru p 9), a recently identified allergen from PT pollen, in exposed workers., Methods: The study included people who reported respiratory symptoms after handling PT in orchards during the flowering period (Blanca village, Murcia region, south-east Spain). After completing a detailed questionnaire, participants underwent skin prick test (SPT) and nasal provocation test (NPT). The IgE response was analysed by SDS-PAGE and immunoblotting assays., Results: A total of 21 cases were included (mean age 45 years; 57% women). Most were polysensitised to common pollens, although one person was sensitised only to PT pollen. All cases had a positive SPT to this pollen, and 43% also to Pru p 9. All participants reported having rhinitis, and six participants reported having also asthma. Immunoblotting showed a heterogeneous IgE pattern for several proteins, with Pru p 9 recognised in nine cases. Most participants sensitised to PT pollen and Pru p 9 had positive NPTs, while those who were not sensitised to Pru p 9 tested negative., Conclusions: We demonstrate for the first time that Pru p 9, an allergen from PT pollen, can induce respiratory symptoms following occupational exposure. This must be considered a relevant allergen when people working with PT cultivars develop respiratory symptoms., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose of Review: To present an update on the recent advances in the understanding of the mechanisms and practical management of oral mite anaphylaxis (OMA, pancake syndrome)., Recent Findings: Among novel observations regarding OMA, this review highlights the increased prevalence of aspirin/NSAID hypersensitivity inpatients affected by OMA, the association of OMA with exercise-induced anaphylaxis, the presentation of OMA simulating acute asthma, the occurrence of OMA in childhood, the high severity and lethal potential of OMA, the contamination of other foods, such as oat and corn flour with mites, and the simultaneous induction of OMA symptoms in more than one individual exposed to the same food source., Summary: OMA is a severe, potentially lethal, acute allergic condition that should be suspected whenever symptoms begin soon after the intake of mite-contaminated foods. Physician awareness on this clinical picture is of paramount importance to establish a correct diagnosis and to implement adequate preventive measures to help patients at risk to avoid its occurrence.

A large number of allergens have been discovered but we know little about their potential to induce inflammation (allergenic activity) and symptoms. Nowadays, the clinical importance of allergens is determined by the frequency and intensity of their IgE antibody binding (allergenicity). This is a rather limited parameter considering the development of experimental allergology in the last 20 years and the criteria that support personalized medicine. Now it is known that some allergens, in addition to their IgE antibody binding properties, can induce inflammation through non IgE mediated pathways, which can increase their allergenic activity. There are several ways to evaluate the allergenic activity, among them the provocation tests, the demonstration of non-IgE mediated pathways of inflammation, case control studies of IgE-binding frequencies, and animal models of respiratory allergy. In this review we have explored the current status of basic and clinical research on allergenic activity of indoor allergens and confirm that, for most of them, this important property has not been investigated. However, during recent years important advances have been made in the field, and we conclude that for at least the following, allergenic activity has been demonstrated: Der p 1, Der p 2, Der p 5 and Blo t 5 from HDMs; Per a 10 from P. americana ; Asp f 1, Asp f 2, Asp f 3, Asp f 4 and Asp f 6 from A. fumigatus ; Mala s 8 and Mala s 13 from M. sympodialis ; Alt a 1 from A. alternata ; Pen c 13 from P. chrysogenum ; Fel d 1 from cats; Can f 1, Can f 2, Can f 3, Can f 4 and Can f 5 from dogs; Mus m 1 from mice and Bos d 2 from cows. Defining the allergenic activity of other indoor IgE antibody binding molecules is necessary for a precision-medicine-oriented management of allergic diseases., Competing Interests: The authors declare that there are not competing interests., (© 2020 The Authors.)

Background: Aedes aegypti and Dermatophagoides pteronyssinus contain important allergens including cross-reactive tropomyosins. However, the functional and clinical relevance of their cross-reactivity is still debated., Objective: To analyse the humoral and cellular cross-reactivity of recombinant Aed a 10.01, Aed a 10.02 and Der p 10., Methods: Sera from 15 Austrian house dust mite-allergic, Der p 10-sensitized individuals were tested for IgE reactivity to recombinant tropomyosins in ELISA, inhibition ELISA and basophil activation tests. BALB/c mice were immunized with Aed a 10.01 or Aed a 10.02, and their sera were assessed for reactivity to all tropomyosins. Splenocytes were stimulated with all tropomyosins and synthetic peptides representing the amino acid sequence of Aed a 10.01., Results: IgE antibodies of Der p 10-sensitized patients cross-reacted with both tropomyosins from A. aegypti. Aed a 10.01 was a more potent inhibitor of IgE binding to Der p 10 and a stronger activator of basophils sensitized with Der p 10-specific IgE than Aed a 10.02. Murine antibodies raised against Aed a 10.01 and Aed a 10.02 cross-reacted with Der p 10. Aed a 10.01-specific antibody showed stronger cross-reactivity with Der p 10 than Aed a 10.02-specific antibody. Splenocytes from both groups of mice proliferated similarly to all tropomyosins. Five cross-reactive T cell-activating regions were identified., Conclusion and Clinical Relevance: Tropomyosins from D. pteronyssinus and A. aegypti show humoral and cellular cross-reactivity, involving 5 potential T cell-activating regions. The more pronounced cross-reactivity of Aed a 10.01 and Der p 10 matched the higher sequence similarity of both proteins., (© 2018 John Wiley & Sons Ltd.)

Background: Cross-reactivity between Aedes aegypti and mites, cockroaches, and shrimp has been previously suggested, but the involved molecular components have not been fully described., Objective: To evaluate the cross-reactivity between A aegypti and other arthropods., Methods: Thirty-four serum samples from patients with asthma and/or allergic rhinitis were selected, and specific IgE to A aegypti, Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis, Periplaneta americana. and Litopenaeus vannamei was measured by enzyme-linked immunosorbent assay. Cross-reactivity was investigated using pooled serum samples from allergic patients, allergenic extracts, and the recombinant tropomyosins (Aed a 10.0201, Der p 10, Blo t 10, Lit v 1, and Per a 7). Four IgE reactive bands were further characterized by matrix-assisted laser desorption/ionization tandem time of flight., Results: Frequency of positive IgE reactivity was 82.35% to at least one mite species, 64.7% to A aegypti, 29.4% to P americana, and 23.5% to L vannamei. The highest IgE cross-reactivity was seen between A aegypti and D pteronyssinus (96.6%) followed by L vannamei (95.4%), B tropicalis (84.4%), and P americana (75.4%). Recombinant tropomyosins from mites, cockroach, or shrimp inhibited the IgE reactivity to the mosquito at a lower extent than the extracts from these arthropods. Several bands of A aegypti cross-reacted with arthropod extracts, and 4 of them were identified as odorant binding protein, mitochondrial cytochrome C, peptidyl-prolyl cis-trans isomerase, and protein with hypothetical magnesium ion binding function., Conclusion: We identified 4 novel cross-reactive allergens in A aegypti allergenic extract. These molecules could influence the manifestation of allergy to environmental allergens in the tropics., (Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Since mite allergens are the most relevant inducers of allergic diseases worldwide, resulting in significant morbidity and increased burden on health services, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), formed by the American Academy of Allergy, Asthma and Immunology (AAAAI), the American College of Allergy, Asthma and Immunology (ACAAI), the European Academy of Allergy and Clinical Immunology (EAACI), and the World Allergy Organization (WAO), has proposed to issue an International Consensus (ICON) on the clinical consequences of mite hypersensitivity. The objectives of this document are to highlight aspects of mite biology that are clinically relevant, to update the current knowledge on mite allergens, routes of sensitization, the genetics of IgE responses to mites, the epidemiologic aspects of mite hypersensitivity, the clinical pictures induced by mites, the diagnosis, specific immunotherapeutic approaches, and prevention.

Purpose of Review: To present currently available information on oral mite anaphylaxis., Recent Findings: Oral mite anaphylaxis (pancake syndrome) is a new syndrome characterized by severe symptoms triggered by the intake of foods containing mites and their allergens. Breathlessness, face and/or laryngeal angioedema, wheezing, rhinorrhea, cough, dysphagia, and wheals are the most frequent clinical manifestations., Summary: Pancake syndrome can occur in individuals at any age and in any geographical location. Foods made with wheat and corn flour, especially pancakes, are the most common inducers of the clinical picture. Both, domestic and storage mites have been incriminated. Increased physician awareness is required for early diagnosis and treatment, and for the prevention of future episodes in predisposed individuals.

Mucosal immunity is the first line of defence of the organism against several pathogens and, at the same time, it is of critical importance in allergic diseases. Oral vaccines have been developed with the aim of enhancing the immune response to pathogens and for the treatment of allergic diseases. One of the major issues concerning oral vaccines is the use of oral adjuvants which could facilitate antigen presentation with the consequent induction of an effective immune response. The present review consists of an analysis, point by point, of the different patents that have been presented in the last 12 months in the different agencies: European (EP), US, and World Intellectual Property Organization (WIPO) and a general analysis of the future developments and trends in this emerging area.

Background: Grasses and olive trees are the most common sources of allergenic pollen worldwide. Although they share some allergens, there are few studies analyzing the in vitro cross-reactivity between them. The aim was to define the cross-reactivity between Olea europaea and Phleum pratense using well-characterized sera of allergic children from Madrid, Spain., Methods: 66 patients (mean age 10.32+/-4.07 years) were included in the study. All suffered from rhinoconjuntivitis and/or asthma and had a positive skin test and/or specific IgE determination to olive and grass pollen. Serum sIgE to individual allergens was conducted and sIgE against different grass species and olive was also determined by ELISA. Inhibition assays were performed using two serum sources, containing, or not, sIgE to minor allergens. Mass spectrometry analysis was performed in both extracts., Results: 59/66 (89.39%) children had a positive sIgE determination by ELISA to grasses and 57/66 (86.36%) to olive pollen. There was no significant correlation between sIgE levels to grass and olive. Inhibition assays demonstrated no cross-reactivity between P. pratense and olive pollen when using the pool containing mainly sIgE to major allergens, whereas minimal to moderate cross-reactivity was detected when the serum contained high sIgE titers to minor allergens. Proteomic analyses revealed the presence of 42 common proteins in grasses and olive pollens., Conclusion: No in vitro cross-reactivity was observed when sIgE was mainly directed to major allergens. In our population, sensitization to olive and grasses is not due to cross-reactivity. The contribution of the major allergens seems to be determinant.

Allergic diseases are a major health problem worldwide. The therapeutic approaches to treat allergic rhinitis (AR) and allergic asthma (AA) fall in three major categories. The first step is allergen avoidance, or reduction of exposure to the offending allergen(s). The second and most widely used therapeutic practice is the prescription of relevant medication to reduce symptoms. The third therapeutic element is specific allergy vaccination, also known as allergen specific immunotherapy. Allergen-specific immunotherapy (SIT) is the only etiologic treatment of allergic disorders that can alter the natural course of the disease. In this review, recent advances in immunotherapy and relevant patents are presented. General vaccine modifications could be applied for any type of allergen. New specific modifications in allergic vaccines have been developed for a variety of allergies such as house dust mites, horse, cat, parvalbumin and from birch, ragweed and parietaria pollen.

Increasing attention has recently been paid to a group of patients who experience anaphylaxis after ingestion of foods prepared with mite-contaminated wheat flour. We present three cases of this syndrome, which occurs more often in young adults with allergic rhinitis and/or asthma. We have observed an increased frequency of sensitivity to aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs), manifested as urticaria or angioedema, in patients with this condition.

Background: The domestic mites Euroglyphus maynei and Blomia tropicalis frequently co-inhabit homes in subtropical/tropical regions around the world. Both species are the source of substances that cause allergic reactions in patients., Objective: The purpose of this study was to examine the immunologic cross-reactivity between E. maynei and B. tropicalis., Methods: Sera of 19 mite-sensitive patients who were skin test positive to B. tropicalis and/or RAST positive to E. maynei were used to probe immunoblots or crossed radioimmunoelectrophoresis (CRIE) gels., Results: Western blotting showed that individual sera had IgE that bound to 0 to 17 and 2 to 15 proteins in E. maynei and B. tropicalis extracts, respectively. Corresponding IgE-binding proteins of 105, 75, 57, 18, and 14 kD were detected in both E. maynei and B. tropicalis extracts. The majority of IgE-binding proteins did not show corresponding bands in both extracts. Heterologous CRIE showed IgE binding to six of the nine E. maynei antigens precipitated by anti-B. tropicalis serum with individual sera recognizing 0 to 4 of the six allergens. In the reciprocal reaction, 10 of the 12 proteins of B. tropicalis that were precipitated by anti-E. maynei serum bound IgE with individual sera binding to 0 to 5 proteins., Conclusion: This study indicated that E. maynei and B. tropicalis are the source of both species-specific and cross-reactive allergens, but most allergens in each extract were species-specific.

Background: Due to low rainfall and high elevation the ten Rocky Mountain states would not be expected to have the indoor humidity required to support the growth of significant numbers of house dust mites. Nevertheless, a recent survey reported that house dust mite allergen levels were not significantly different in the various regions of the United States, including the arid and mountainous regions., Methods: Each summer for 5 years (1988-92) patients with bronchial asthma scheduled to be evaluated at the National Jewish Center for Immunology and Respiratory Medicine were invited to submit a dust sample from their mattress or bedroom carpet for mite analysis., Results: Fifty-eight patients from the ten Rocky Mountain states submitted dust specimens. Forty-eight contained no mites, five had levels of mites considered clinically insignificant (less than 100 mites/g dust), three contained 100 mites/g of dust, a level at the threshold of significance, and two had high levels of mites (1,000 and 3,000 mites/g). Both of the homes with high mite levels had specific sources of excess moisture. Twenty-eight patients from adjacent states also submitted dust specimens. Significant levels of mites were encountered in specimens from these states reflecting the transition to zones of greater humidity and lower elevation., Conclusion: Except in homes with unusual sources of humidity, significant levels of house dust mites are rarely encountered in homes in the ten Rocky Mountain states.

Background: English plantain (Plantago lanceolata) weed pollen and psyllium (Plantago ovata) husk dust are inhalant allergens. Because of the phylogenetic relationship between these plant species, cross-allergenicity has been a concern., Objective: The purpose of this study was to investigate the possible cross-allergenicity of plantain and psyllium., Methods: Homologous and heterologous crossed immunoelectrophoresis (CIE) were performed using a commercial English plantain pollen extract and an extract of psyllium seed embryo. Crossed radioimmunoelectrophoresis (CRIE) was performed using sera from subjects who were RAST positive only to plantain (group A), RAST positive only to psyllium (group B), RAST positive to both plantain and psyllium (group C), or RAST negative to both (group D)., Results: All of the group A plantain subjects showed IgE binding to at least one of the six plantain allergens in homologous plantain CRIEs while only one of the sera from the group B subjects reacted very weakly to these plantain allergens. In homologous psyllium CRIE, all group B subjects showed pronounced IgE binding to 2 to 7 of the seven psyllium allergens. Several of the plantain subjects demonstrated only very weak binding to psyllium allergens. Heterologous CRIEs demonstrated little relevant IgE binding., Conclusions: These results indicate that there is little cross-allergenicity between psyllium husk and English plantain pollen.

We compared exposure and levels of IgE and IgG antibodies to inhalant allergens in 20 children with asthma and positive skin tests to Dermatophagoides pteronyssinus, living in São Paulo, to 20 control children without history of asthma or allergy and negative skin tests to D. pteronyssinus, D. farinae, and Blomia tropicalis. In 16/20 and 17/20 houses of asthmatic and control children, respectively, at least one sample was obtained which contained > 10 micrograms Der p I/g of dust. Serum IgE antibodies to D. pteronyssinus and Blomia tropicalis were > 200 RAST U/mL in 19/20 and in 16/20 asthmatic children, respectively. In the control group, IgE antibodies to either mite species were < 40 RAST U/mL in most cases. IgG anti-Der p I and anti-Der f I antibodies were detected in 17/20 asthmatics, as opposed to 3/20 controls. Neither cat nor cockroach allergens caused significant sensitization among asthmatic or control children. Although exposure to high levels of mite allergens was common in São Paulo, significant IgE and IgG antibody responses were detected only in children with asthma.

Background: The house dust mite, Euroglyphus maynei (EM), is common in homes in England, Europe, the southern United States, and other parts of the world. It is often present in densities greater than 100 mites per gram of dust. EM usually occurs with Dermatophagoides farinae (DF) and D. pteronyssinus (DP) and it is frequently more abundant than Dermatophagoides species. Therefore the allergenicity of EM and the cross-reactivity between EM and Dermatophagoides species are important considerations for diagnosis of mite-induced allergy and the use of appropriate immunotherapy., Methods: Crossed immunoelectrophoresis revealed that EM was the source of at least 33 antigens. Crossed radioimmunoelectrophoresis with 32 different sera from patients with RAST results that were positive to EM and skin test results that were positive to both DF and DP identified 15 allergens. Individual sera recognized two to eight EM antigens as allergens., Results: Ninety-one percent of the patients showed serum IgE directed at three or more allergens. Eighty-four percent of the patients had moderate or strong levels of IgE directed at antigen no. 33. All 15 allergens showed moderate or strong IgE binding by one or more sera. EM shared four and six cross-reacting allergens with DF and DP, respectively. Therefore 11 and 9 allergens of EM were species-specific and not shared by DF and DP, respectively., Conclusions: The results of this study clearly indicate that sensitivity to EM should be considered in geographic areas where this mite is abundant in homes.

Background: Blomia tropicalis (BT) occurs in a significant percentage of homes in tropical and subtropical geographic regions of the United States and Europe and in countries in South America and Asia along with the pyroglyphid mites, Euroglyphus maynei (EM), Dermatophagoides pteronyssinus, and D. farinae. Blomia species may be major sources of allergens in house dust in addition to Dermatophagoides species and E. maynei., Methods: Crossed immunoelectrophoresis and crossed radioimmunoelectrophoresis were used to identify the antigens and allergens of BT and to determine the cross-reactivity between BT and the house dust mites, D. farinae, D. pteronyssinus, and the stored product mite, Tyrophagus putrescentiae., Results: Homologous crossed immunoelectrophoresis of BT resulted in 27 antigen-antibody complexes. Crossed radioimmunoelectrophoresis of these gels showed 21 different immunoglobulin E binding antigens when they were incubated in the sera from 14 patients with asthma whose radioallergosorbent test and skin test results were positive. Heterologous crossed immunoelectrophoresis reactions with BT and rabbit D. farinae body and feces, D. pteronyssinus body and feces, and T. putrescentiae body and feces antisera resulted in one to four precipitin lines. BT extract, reacted with rabbit antisera produced against the bodies of D. farinae, D. pteronyssinus, and T. putrescentiae, produced 3, 2, and 4 antigenic peaks, respectively; whereas crossed radioimmunoelectrophoresis of these gels with the sera of the 14 patients with asthma resulted in immunoglobulin E binding to 2, 2, and 4 peaks, respectively., Conclusions: The results of this study indicated that BT contained multiple allergens of which most were species-specific. There was a limited amount of cross-reactivity between BT and the two common house dust mite species and the stored product mite. The amount of cross-reactivity appears to parallel the phylogenetic relatedness.

Southern bayberry, distributed throughout the southeastern United States, is the source of the fifth most common windborne tree pollen in Tampa, Fla. Fifteen percent of 400 consecutive subjects evaluated for allergic respiratory symptoms in the Tampa Bay area had positive skin tests to bayberry pollen extract. Bayberry pollen extract was obtained commercially and used to perform 25 nasal and 22 bronchial challenges on 45 subjects. Twelve of 13 (92%) study subjects with allergic rhinitis and positive skin tests to bayberry pollen extract and two of 12 (17%) control subjects with negative skin tests had positive nasal challenges (p = 0.0001). Four of seven (57%) study subjects with extrinsic asthma and positive skin tests to bayberry pollen extract and none of the 15 (0%) control subjects with negative skin tests had positive bronchial challenges (p = 0.001). Sera from 30 subjects who underwent 31 challenges were assayed for bayberry pollen extract-specific IgE by plate radioimmunoassay. Specific IgE antibodies were present in the sera of 8 of 13 (62%) subjects with positive challenges and absent in 15 of 18 (83%) subjects with negative challenges (p = 0.01). Intradermal skin tests with bayberry pollen extract were more predictive of provocation challenge results than plate radioimmunoassay (positive predictive value of 80%, 95% CI 62% to 98%; versus 73%, 95% CI 47% to 99%). Bayberry pollen extract is allergenic, and the Southern bayberry tree fulfills Thommen's criteria defining aeroallergen-producing plants.

An aerobiologic survey using a rotoslide sampler was conducted daily (January 1979 through December 1981) in Tampa, Florida. A major tree pollen season (Dec. through May) consisted of oak, pine, Australian pine, bald cypress, cedar, bayberry and mulberry. A minor tree season (Oct. and Nov.) consisted of Australian pine and elm. Grass pollen was found throughout the year and most prevalent April through October. A major weed pollen season (May through Dec.) consisted of ragweed, Mexican tea, pigweed, dog fennel, and false nettle. A minor weed season (March through July) consisted of sorrel and dock.

A group of 20 mite allergic asthmatic children aged 6-12 years old, living in São Paulo, Brazil, was studied regarding their degree of sensitization to house dust mites and exposure to mite allergens in their homes. In 18 out of 20 houses at least one dust sample was obtained which contained greater than 10 micrograms Der p I/g of dust. The highest levels of Dermatophagoides pteronyssinus allergens, Der p I and Group II, were measured in bedding samples (geometric mean 38.4 and 36.6 micrograms/g, respectively), followed by bedroom floor, TV room and kitchen. Mite allergen levels in Brazilian houses were as high as those reported to be associated with sensitization and acute attacks of asthma in other parts of the world. In keeping with previous reports that D. farinae is rarely found in Brazil, Der f I was undetectable or found in very low levels (less than 0.5 micrograms/g). Levels of cat allergen Fel d I of greater than 8 micrograms/g of dust were obtained only in 2 houses only. Cockroach allergen Bla g I was detected in five out of 20 houses. Levels of IgE antibodies to D. pteronyssinus were greater than 200 RAST U/ml in 19 out of 20 children (geometric mean 1588 RAST U/ml). IgE antibodies to cat, cockroach, A. fumigatus, ragweed and rye grass pollens were undetectable or less than 80 RAST U/ml. IgE antibodies to the mite Blomia tropicalis were also measured, and levels greater than 200 RAST U/ml were observed in 13 out of 20 sera.(ABSTRACT TRUNCATED AT 250 WORDS)

A sandwich ELISA was developed to measure the concentration of cockroach allergen in the environment. The assay was based on a monospecific rabbit antibody preparation reactive with determinants shared by the important allergens, Per a I and Bla g I, from American and German cockroaches. The sensitivity was 0.2 ng Lowry protein of Per a I equivalents per milliliter, corresponding to 1 ng of Per a I equivalents per gram of dust (Per a I eq/gm). The assay did not react with noncockroach-allergen sources. Dust samples from 73 households in a cockroach-infested area were assayed. The concentration in these samples varied from below detection to 200,000 ng of Per a eq/gm of dust. Three commercial cockroach-allergen extracts all contained the allergen. The assay will be valuable for studies of the clinically relevant cockroach-allergen exposure levels and for assessment of efficacy of allergen-avoidance measures. Furthermore, the assay could be used for sanitary documentation in bakeries, restaurants, etc.

Airborne soybean allergens in the dust generated during the unloading of soybeans in the harbor caused asthma epidemics in Barcelona, Spain. The major allergen causing the epidemics was a glycopeptide less than 14 kd molecular mass abundant in soybean dust. This allergen occurs in all parts of the soybean plant at all stages of growth, but the telae (hulls) and pods are by far the richest source. Small amounts of a similar cross-reacting allergen are found in some other grain dusts. The botanical function and significance of this soybean plant component is not known nor is the potential for airborne dispersion of this allergen at other grain-handling sites.

Aqueous whole body extracts from two major domiciliary cockroaches, the American, Periplaneta americana, and the German, Blattella germanica, were analyzed in crossed immunoelectrophoresis and immunoblotting. Forty-five antigens were found in P. americana and 29 in B. germanica. IgE-binding antigens were identified by crossed radioimmunoelectrophoresis with sera from 30 cockroach-allergic patients. Seven and three precipitates from P. americana and B. germanica bound significant amounts of IgE. A cross-reactive, apparently homologous allergen, from P. americana and B. germanica bound IgE from 100% and 70%, respectively, of the patients. These important allergens were tentatively named Per a I and Bla g I. The allergens were purified by sequential ion exchange, gel filtration, and isoelectric focusing. Both allergens had a molecular size of 33 to 37 kd in Sephadex G-75 gel filtration, and 28 kd in high-performance liquid chromatography gel filtration. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed a minor band at approximately 25 kd, and most of the protein at 6 kd. The isoelectric point of both allergens was found be to 3.5. In amino acid analysis, the allergens were highly similar. Skin test revealed the allergens to be important in vivo sensitizing agents. The allergens may be used for environmental assays for cockroach exposure in the homes of allergic subjects.

Human immunodeficiency virus infection is characterized by a progressive depletion of helper T-lymphocytes and, like allergic diseases, is associated with altered T cell regulation. Total serum IgE was measured in 67 infected male subjects, 27 uninfected heterosexual male subjects, and 18 uninfected homosexual male subjects. The mean IgE level (132 IU/ml) of infected subjects with a helper T-lymphocyte number less than or equal to 200/mm3 was significantly greater than mean IgE levels of the uninfected heterosexual (38 IU/ml) and homosexual (35 IU/ml) groups. IgE levels were inversely related to both helper T cell and suppressor/cytotoxic T cell numbers but not to IgG or IgA levels. The increase in IgE was not a reflection of an increased prevalence of atopic disease (allergic asthma, allergic rhinitis, or atopic dermatitis) in the infected subjects. The elevation of IgE may be related to a difference among the groups in T cell production of IgE regulatory lymphokines.