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The major allergens from the mouse, including mouse serum albumin (MSA) and mouse urinary protein complex, are present in various concentrations in urine, serum, and pelts of mice. Subjects clinically sensitive to laboratory animals were screened by the RAST for specific IgE antibodies to mouse urine (MU), MSA, and mouse pelt extract (MPE). Twenty-four hour air samples from both a mouse-care room (2000 mice) and an immunology laboratory (five to 100 mice) were collected with a high-volume air sampler that retained particles greater than 0.3 μm with 95% efficiency. Eluates from the filter sheets were dialyzed, lyophilized, reconstituted in water, and used as fluid-phase inhibitors in the MU RAST and MPE RAST. MPE allergenic activity could be quantitated in filter eluates from both locations, but MU allergenic activity could be quantitated only in the mouse-care room. Airborne allergen content ranged from 1.8 to 825 ng/m 3 and varied with both the number of mice and the degree of work activity in the rooms. The sampling and assay techniques described can be used to accurately quantitate amorphous airborne allergens.

To define airborne allergen exposure during various tasks with rats in a laboratory, concentrations of allergen Rat n I were measured by radioimmunoassay in extracts from filters in personal air sampling devices that were worn by laboratory workers while they were performing these tasks. The tasks included feeding, cage cleaning, handling, injection, surgery, and sacrifice. Median concentrations encountered during feeding or cleaning (21 ng/m3) and injection or handling (13 ng/m3) were higher than those associated with surgery or sacrifice (3.1 ng/m3; p less than 0.01). Area samples in animal-holding rooms contained 3.4 ng/m3 during animal handling and 2.3 ng/m3 at other times. Very low concentrations were found in air outside the handling room, in unused laboratories, or outside air. We concluded that certain tasks incur a higher risk of allergen exposure but that exposure may occur anywhere within an animal laboratory environment.

A clinical study of patients with intractable asthma coming to the new Judean desert town of Arad was carried out concurrently with an aerobiological survey. Pollen and mold concentrations in the air of Arad were about one third and one half, respectively, of those in the central coastal region of Israel. Excellent to moderate clinical responses to the stay in Arad were observed in 84 per cent of the asthmatic subjects. The moderate reduction of pollen and mold spore content in the air of Arad is not a satisfactory explanation for the beneficial results. The reason for improvement of asthmatics in desert climates in many instances still remains unsolved.

The practice of avoiding exposure to allergens (allergen avoidance) for allergic diseases such as asthma is not a new idea. In the 16th century the Archbishop of St Andrews had a miraculous remission of his intractable asthma by getting rid of his feather bedding, and in 1927 Storm van Leeuwen created a “climate chamber” in Holland in an attempt to recreate the beneficial environment of high altitude sanatoriums. This article focuses on how to avoid indoor allergens in homes in temperate climates and the potential benefits for sensitised patients with atopic disorders. Amount of time that most Americans spend indoors, outdoors, and in transit Nowadays most people spend more than 90% of their lives indoors. Over the past 30 years, the home environment has changed enormously with the introduction of soft furnishings, fitted carpets, and central heating. Indoor ventilation has decreased—the rate at which indoor air is exchanged for fresh air is now 10 times lower than it was 30 years ago, with a considerable increase both in humidity and in concentrations of indoor pollutants and airborne allergens. As exposure to allergens is an important cause of symptoms in sensitised patients, reducing exposure should improve disease control. In spite of this, few patients in Britain with asthma, eczema, or perennial rhinitis, or any combination of these, are skin tested. Few patients in Britain with asthma, eczema, or perennial rhinitis receive advice on appropriate avoidance measures The predominant indoor allergens in Britain are from mites, cats, and dogs, and they have dramatically different aerodynamic characteristics. Mite allergens are present on large particles in beds, soft furnishings, and carpets, which become airborne only after vigorous disturbance and settle quickly. In contrast, about 25% of cat and dog allergens are associated with small particles

Background The galactose-α1,3-galactose (α-Gal) syndrome (AGS) is a novel form of food allergy. Patients experience delayed severe allergic reactions after mammalian meat consumption due to IgE antibodies directed against the carbohydrate α-Gal present in mammalian meat. The onset of the disease is associated with tick bites. Objective To characterize a cohort of patients with AGS from Sweden on a clinical and serological level, and identify risk factors for disease severity. Methods A total of 128 patients with symptoms after mammalian meat intake and IgE to α-Gal were included. Medical examination and diagnosis were made by an allergologist and questionnaires were filled in regarding onset of symptoms, tick exposure, and airborne allergies. Serum IgE reactivity against multiple food and airborne allergens, as well as protein extract from the tick Ixodes ricinus, was measured using ImmunoCAP. Results The majority of patients were middle aged, with equal gender distribution. Nearly all reported symptoms more than 2 hours after meat consumption. Urticaria (90%) and gastrointestinal symptoms (74%) were most common. Almost half of the patients suffered from anaphylaxis, and α-Gal IgE levels were significantly higher among these patients compared with those without anaphylaxis. Nearly all patients had been tick bitten and 75% had IgE against I. ricinus. More than half of the patients with AGS were atopic, and atopy increased the risk of anaphylaxis with pulmonary manifestations. Only 2 patients belonged to blood group B/AB. Conclusion AGS is an upcoming food allergy where patients report severe symptoms and tick bites. Atopy was found to affect the manifestation of the disease in Swedish patients.

Atopic diseases including asthma, rhinitis and eczema have increased in the second half of the past century. This has been well studied among children and adolescents but with the exception of asthma to a much lesser extent in adults. The adult risk factor pattern of atopic diseases, in particular of eczema, and their relation to allergic sensitization are yet to be fully elucidated. Studies among adults that have compared the risk factor pattern for these conditions in the same material are very few. The objective of this study was to compare the risk factor patterns for asthma, rhinitis and eczema in a randomly selected adult population. A questionnaire survey on atopic diseases was dispatched by mail to 30,000 randomly selected individuals in West Sweden aged 16–75 years and 62 % participated. A subgroup of 2000 individuals was selected for clinical examinations including blood sampling for specific serum Immunoglobulin E to common airborne allergens and 1172 attended. The prevalence of current asthma was 11.8 %, current rhinitis 42.8 %, current eczema 13.5 and 2.3 % had all three conditions while 13.9 % had at least two conditions. No mutual risk factor was identified for all three conditions. Allergic sensitization was a strong risk factor for current asthma (OR 4.1 CI 2.7–6.3) and current rhinitis (OR 5.1 CI 3.8–6.9) but not so for current eczema. Obesity was a risk factor for current asthma and current rhinitis, while farm childhood decreased the risk for current asthma and current rhinitis. Occupational exposure to gas dust or fumes and female sex was associated with an increased risk of current asthma and current eczema. There are different risk factor patterns for asthma, rhinitis and eczema in adults but some risk factors are overlapping between some of the conditions. The effect of mutable risk factors should be assessed further in longitudinal studies.

Objective: To investigate the working hypothesis that common infections occurring early in life prevent atopy. Design: Cross sectional, retrospective study of young Italian men with results for hepatitis A serology and atopy. Setting: Air force school for military students in Caserta, Italy. Subjects: 1659 male students aged 17-24, most of whom (90%) were from central and southern Italy. Main outcome measures: Skin sensitisation and specific IgE antibodies to locally relevant airborne allergens; diagnosis of respiratory allergy (asthma or rhinitis, or both); hepatitis A seropositivity. Results: 443 of the 1659 subjects (26.7%) were positive for hepatitis A virus antibody. Atopy was less common among seropositive than seronegative subjects according to skin sensitization (weal reaction ≥3 mm) to one or more allergens (21.9% (97/443) v 30.2% (367/1216), P v 6.4% (78/1216), P v 18.4% (224/1216), P v 16.7% (203/1216), P Conclusion: Indirect but important evidence is added to the working hypothesis as common infections acquired early in life because of the presence of many older siblings (among seronegative subjects) or because of unhygienic living conditions (among seropositive subjects) may have reduced the risk of developing atopy. Key messages Young men with antibodies to hepatitis A virus had a lower prevalence of atopy and atopic respiratory diseases, and this was independent of the number of older siblings and other relevant risk factors The prevalence of atopy was as low in seronegative as in seropositive subjects only when they had three or more older siblings Among seropositive subjects the prevalence of atopy was low, whatever the number of older siblings Common infections acquired early in life because of the presence of many older siblings (among seronegative subjects) or because of unhygienic living conditions (among seropositive subjects) may have reduced the risk of development of atopy This study adds indirect but important evidence to the hypothesis that improvements in hygiene and reduced recirculation of common infections may be a major cause of the increasing prevalence of atopy and atopic diseases in Western countries

Background Sensitization to aeroallergens increases the risk of developing asthma or allergic rhinitis. Data on sensitization to airborne allergens in the general population in sub-Saharan Africa are lacking. The aim of this study was to determine the prevalence and determinants of sensitization to common aeroallergens in a population of young adults. Methods A cross-sectional study was conducted among students of the Faculty of Medicine and Pharmaceutical Sciences of the University of Douala between 1st February and 30th April 2014. We consecutively recruited all the students present in class or in hospital during our visit. They filled an anonymous questionnaire and underwent skin prick tests with common aeroallergens. A logistic regression model of the SPSS.20 software was used to investigate factors associated with sensitization to common aeroallergens. Results Of the 600 students included in the study, 305 (50.8 %) were female. The mean age of participants was 22.6 ± 2.7 years. The prevalence of sensitization to aeroallergens was 42.8 % (95 % CI 38.8–46.8). Dermatophagoides pteronyssimus (24.2 %), Dermatophagoides farinae (22.8 %), Blomia tropicalis (23.3 %) and Blatella germanica (15.2 %) were the most common allergens found. Allergic rhinitis, asthma symptoms and family atopy were independently associated to sensitization to common aeroallergens. Conclusion A significant proportion of young adults are sensitized to common aeroallergens. Dust mites and cockroach should be included in the panel of aeroallergens in Cameroon.

Fourteen patients with suspected food-dependent, exercise-induced anaphylaxis (EIAn) were subjected to prick tests with commercial food extracts and common airborne allergens, prick + prick tests with fresh foods, determination of total IgE levels, and specific IgE for 31 foods (CAP System FEIA RAST). All were positive for two or more foods; 10 presented hypersensitivity to 11 or more foods. On the basis of these findings, history data, and responses to food-exercise challenges (treadmill stress tests 90 min after meals containing none of the suspected foods and none associated with skin-test and/or RAST positivity) and suspected food-exercise challenges (SFECs - administered after meals containing the suspected food), three patients were diagnosed as having specific food-dependent EIAn (for wheat in two cases, tomato in one). In nine others, the presence of specific IgE for numerous foods (including those suspected on the basis of histories and utilized in the SFECs) suggests involvement of specific food hypersensitivity, although SFEC confirmation could not be obtained. Avoidance of all foods associated with test positivity 4 h before exercise has prevented all further EIAn episodes in these 12 patients. In two others, the reactions did not appear to be related to IgE directed against specific food allergens, and these subjects have eliminated further reactions by avoiding all meals for the 4 h preceding exercise. These findings emphasize the importance of allergologic testing with a wide panel of food allergens (including foods used for seasoning, such as garlic or parsley) in all patients with suspected food-dependent EIAn. Prick + prick tests with fresh foods and the CAP System RAST disclosed numerous hypersensitivities.

DNA methylation changes may predispose becoming IgE-sensitized to allergens. We analyzed whether DNA methylation in peripheral blood mononuclear cells (PBMC) is associated with IgE sensitization at 5 years of age (5Y). DNA methylation was measured in 288 PBMC samples from 74 mother/child pairs from the birth cohort ALADDIN (Assessment of Lifestyle and Allergic Disease During INfancy) using the HumanMethylation450BeadChip (Illumina). PBMCs were obtained from the mothers during pregnancy and from their children in cord blood, at 2 years and 5Y. DNA methylation levels at each time point were compared between children with and without IgE sensitization to allergens at 5Y. For replication, CpG sites associated with IgE sensitization in ALADDIN were evaluated in whole blood DNA of 256 children, 4 years old, from the BAMSE (Swedish abbreviation for Children, Allergy, Milieu, Stockholm, Epidemiology) cohort. We found 34 differentially methylated regions (DMRs) associated with IgE sensitization to airborne allergens and 38 DMRs associated with sensitization to food allergens in children at 5Y (Sidak p ≤ 0.05). Genes associated with airborne sensitization were enriched in the pathway of endocytosis, while genes associated with food sensitization were enriched in focal adhesion, the bacterial invasion of epithelial cells, and leukocyte migration. Furthermore, 25 DMRs in maternal PBMCs were associated with IgE sensitization to airborne allergens in their children at 5Y, which were functionally annotated to the mTOR (mammalian Target of Rapamycin) signaling pathway. This study supports that DNA methylation is associated with IgE sensitization early in life and revealed new candidate genes for atopy. Moreover, our study provides evidence that maternal DNA methylation levels are associated with IgE sensitization in the child supporting early in utero effects on atopy predisposition.

THE aerial dissemination of certain types of fungus spores has been studied intensively by plant pathologists, and the literature on spore dispersal in general has been summarized from this point of view by Gregory1. Mould spores, however, not only cause infective disease in plants but may, as airborne allergens, also give rise to disease in man, and numerous studies have established their importance as a cause of asthma2,3.

Allergen skin-prick tests to the common airborne allergens were performed on 534 children with asthma. A positive reaction to one or more allergens was observed in 81%, and the prevalence increased with age. The specific allergen reactions were characteristic with a high prevalence of reactions to house-dust mite (Dermatophagoides pteronyssinus) (88%), house dust (79%, and cat fur (62%), and a low prevalence of grass-pollen reactions (12% to 25%). We found that the diagnosis of atopy could be made in virtually all (96%) of these children by using only three allergens: D. pteronyssinus, cat fur, and rye grass.

The purpose of this volume is to furnish the reader with an understanding of the behavior of airborne material as it reaches the respiratory tract. Professor Muir leads off with an excellent discussion of the physics of aerosols, essential to understanding of effects. His lucid presentation of air-flow characteristics in the successive orders of bronchi, the effective diameter of particles in the aerosols, sites of deposition along the airways, and clearance mechanisms is full yet concise. He expands these ideas further and effectively in two other chapters, one dealing with airborne allergens, the other with physical properties of therapeutic aerosols. Professor Lawther presents the chapter on "Air Pollution and Tobacco Smoke" and points out the numerous inadequacies in our knowledge of effects. Dr. Williams deals with airborne microbial infection, and is particularly good on the subject of air disinfection. Dr. Schilling presents byssinosis, while Dr. Elmes discusses asbestosis. The chapter