Article

Can f 1 levels in hair and homes of different dog breeds: Lack of evidence to describe any dog breed as hypoallergenic

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Abstract

Certain dog breeds are described and marketed as being "hypoallergenic" on the basis of anecdotal reports that these dogs are better tolerated by patients allergic to dogs. These observations were investigated by comparing Can f 1 (major dog [Canis familiaris] allergen) levels in hair and coat samples and in the home environment of various hypoallergenic (Labradoodle, Poodle, Spanish Waterdog, and Airedale terrier) and non-hypoallergenic dogs (Labrador retriever and a control group). Hair and coat samples were obtained from dogs, and settled floor and airborne dust samples were taken from the dogs' homes. Can f 1 concentrations were measured by using ELISA, and results were analyzed by using multiple linear regression analyses. Significantly higher Can f 1 concentrations were found in hair and coat samples of hypoallergenic dogs (n = 196, geometric mean [GM], 2.26 μg/g, geometric standard deviation [GSD], 0.73, and GM, 27.04 μg/g, GSD, 0.57, respectively) than of non-hypoallergenic dogs (n = 160, GM, 0.77 μg/g, GSD, 0.71, and GM, 12.98 μg/g, GSD, 0.76, respectively). Differences between breeds were small, relative to the variability within a breed. Can f 1 levels in settled floor dust samples were lower for Labradoodles, but no differences were found between the other groups. No differences in airborne levels were found between breeds. So-called hypoallergenic dogs had higher Can f 1 levels in hair and coat samples than did control breeds. These differences did not lead to higher levels of environmental exposure to dog allergens. There is no evidence for the classification of certain dog breeds as being "hypoallergenic."

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... Similar results had been previously obtained in investigations of dog or bovine hair samples. The content of the major dog allergen, Can f 1 differed up to four orders of magni- tude [30,31], and the major bovine allergen, Bos d 2 varied up to three orders of magnitude among individual animals [24]. A wide variation in allergen concentrations was also observed among animals of the same breed from each species. ...
... Paradoxically, the so-called hypoallergenic Curly Horses had significantly higher HD antigen, Equ c 1 and Equ c 4 levels in hair than the majority of other investigated breeds. These results are in accordance with previous studies that have shown significant dif- ferences in Can f 1 levels among dog breeds [30,31]. Both studies have found that Poodles had the highest and Labrador Retrievers had the lowest Can f 1 concentrations in hair. ...
... Both studies have found that Poodles had the highest and Labrador Retrievers had the lowest Can f 1 concentrations in hair. Moreover, a study by Vredegoor et al. showed significantly higher Can f 1 levels in hair of hypoallergenic dogs, such as Labradoodle, Poodle, Spanish Waterdog, and Airedale terrier (geometric mean (GM), 2.26 μg/g) compared to hair from non-hypoallergenic dogs (GM, 0.77 μg/g) [31]. In contrast, there were no significant differences in Bos d 2 levels in bovine hair among different breeds [24]. ...
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Background Exposure to horses can cause severe allergic reactions in sensitized individuals. The breed, American Bashkir Curly Horse is categorized as hypoallergenic, primarily due to reports of allergic patients experiencing fewer symptoms while handling this special breed. The possible reasons for this phenomenon could be lower allergen production and/or reduced allergen release into the air because of increased sebum content in their skin and hair compared to other breeds. Therefore, the aim of the current study was to compare different horse breeds in relation to allergen content in hair and airborne dust samples. Methods In total, 224 hair samples from 32 different horse breeds were investigated. Personal nasal filters were used to collect airborne dust during the grooming of 20 Curly Horses and 20 Quarter Horses. Quantitative analysis of all samples was performed using two newly developed immunoassays for the detection of horse dander (HD) antigens and the major allergen Equ c 1 and the commercial assay for Equ c 4. Results were analyzed using multiple linear regression models for hair samples and the Mann Whitney U test for airborne samples. Results Horse antigen and allergen levels differed up to four orders of magnitude between individual animals. Despite enormous variability, levels of HD antigen, Equ c 1 and Equ c 4 in hair were significantly related to the breed and gender combined with the castration status of male animals. Curly Horses had significantly higher concentrations of all three tested parameters compared to the majority of the investigated breeds (medians: 11800 μg/g for HD antigen, 2400 μg/g for Equ c 1, and 258 kU/g for Equ c 4). Tinker Horses, Icelandic Horses and Shetland Ponies were associated with approximately 7-fold reduced levels of HD antigen and Equ c 1, and up to 25-fold reduced levels of Equ c 4 compared to Curly Horses. Compared to mares, stallions displayed increased concentrations of HD antigens, Equ c 1 and Equ c 4 by a factor 2.2, 3.5 and 6.7, respectively. No difference was observed between mares and geldings. No differences in airborne allergen concentrations collected with personal nasal filters during grooming were found between Curly and Quarter Horses. Conclusion Breed and castration status had a significant influence on the antigen and allergen levels of horse hair. However, these differences were smaller than the wide variability observed among individual horses. Compared to other breeds, Curly Horses were not associated with lower allergen levels in hair and in air samples collected during grooming. Our approach provides no molecular explanation why Curly Horses are considered to be hypoallergenic.
... There is no scientific evidence to support labelling certain breeds of cats or dogs as hypoallergenic, since no significant differences have been found between environmental levels of allergens from non-hypoallergenic dogs versus so-called hypoallergenic dogs (14,58,69). ...
... Therefore, the availability of a genuinely allergen-free dog for allergic individuals who would like to have a dog is questionable (70). Patients should not be advised on the safety of acquiring a "hypoallergenic" dog or cat (14,58,69) [Recommendations 24 and 25, Table 2]. ...
... : Based on (14,58,69) 25 ...
Article
The prevalence of sensitisation to dogs and cats varies by country, exposure time and predisposition to atopy. It is estimated that, 26% of European adults coming to the clinic for suspected allergy to inhalant allergens are sensitised to cats and 27% to dogs. This document is intended to be a useful tool for clinicians involved in the management of people with dog or cat allergy. It was prepared from a consensus process based on the RAND/UCLA method. Following a literature review, it proposes various recommendations concerning the diagnosis and treatment of these patients, grounded in evidence and clinical experience. The diagnosis of dog and cat allergy is based on a medical history and physical examination that are consistent with each other, and is confirmed with positive results on specific IgE skin tests. Sometimes, especially in polysensitised patients, molecular diagnosis is strongly recommended. Although the most advisable measure would be to avoid the animal, this is often impossible and associated with a major emotional impact. Furthermore, indirect exposure to allergens occurs in environments in which animals are not present. Immunotherapy is emerging as a potential solution to this problem, although further supporting studies are needed.
... In that study, the golden retriever and Dogue de Bordeaux had lower Can f 1 than other breeds. In another study, Can f 1 measured in dander extracts also varied across breeds of dogs: Can f 1 in dander was lower in golden retrievers and Labrador retrievers, and higher in breeds purported to be hypoallergenic [15]. ...
... The results from this study corroborate other studies that report equivalent expression of Can f 1 between male and female dogs [15]. The expression profile of Can f 1 did not significantly vary throughout the day nor in relationship to feeding, indicating that a single assessment of salivary protein would be representative of a dog's propensity to evoke allergies through Can f 1. ...
... A study measuring Can f 1 levels in dander extracts from Labrador retrievers, Labradoodles, poodles, Spanish waterdogs, Airedale terriers, and a control group of non-hypoallergenic dog breeds and crossbreds, showed significant differences in variability of Can f 1 both between dog breeds and across individuals within the same breed. Labrador retrievers had the lowest Can f 1 concentration and Poodles had the highest Can f 1 concentration [15] consistent with results of the current study. Another study [21] also using dander extracts likewise demonstrated that golden retrievers had higher Can f 1 concentrations than Labrador retrievers. ...
Article
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Background: Valued for trainability in diverse tasks, dogs are the primary service animal used to assist individuals with disabilities. Despite their utility, many people in need of service dogs are sensitive to the primary dog allergen, Can f 1, encoded by the Lipocalin 1 gene (LCN1). Several organizations specifically breed service dogs to meet special needs and would like to reduce allergenic potential if possible. In this study, we evaluated the expression of Can f 1 protein and the inherent variability of LCN1 in two breeds used extensively as service dogs. Saliva samples from equal numbers of male and female Labrador retrievers (n = 12), golden retrievers (n = 12), and Labrador-golden crosses (n = 12) were collected 1 h after the morning meal. Can f 1 protein concentrations in the saliva were measured by ELISA, and the LCN1 5' and 3' UTRs and exons sequenced. Results: There was no sex effect (p > 0.2) nor time-of-day effect; however, Can f 1 protein levels varied by breed with Labrador retrievers being lower than golden retrievers (3.18 ± 0.51 and 5.35 ± 0.52 μg/ml, respectively, p < 0.0075), and the Labrador-golden crosses having intermediate levels (3.77 ± 0.48 μg/ml). Although several novel SNPs were identified in LCN1, there were no significant breed-specific sequence differences in the gene and no association of LCN1 genotypes with Can f 1 expression. Conclusions: As service dogs, Labrador retrievers likely have lower allergenic potential and, though there were no DNA sequence differences identified, classical genetic selection on the estimated breeding values associated with salivary Can f 1 expression may further reduce that potential.
... We measured the concentration of the most potent dog allergen, Can f1, a salivary lipocalin, also found in dog hair. 4,5 Immunoglobulin E (IgE) immunoblotting was used to determine the components in the allergen extracts that reacted to IgE in pooled sera from dog allergen-sensitized patients. Differences among dog breeds and various factors were analyzed using the Kruskal-Wallis and Mann-Whitney tests, respectively. ...
... There has been no evidence of low allergenicity in so-called hypoallergenic breeds. Additionally, we found that the allergenicity of dog hair varies among individuals of the same breed, as reported previously, 4,5 and that the concept of a "hypoallergenic" animal is currently not supported by scientific evidence. https://e-aair.org ...
... Certain dog breeds are being marketed as being hypoallergenic without reliable scientific evidence (27), and some recent studies suggest no evidence of hypoallergenic dog breeds (27,28). However, the possible different allergenicity of different dog breeds has been described (29)(30)(31). ...
... Certain dog breeds are being marketed as being hypoallergenic without reliable scientific evidence (27), and some recent studies suggest no evidence of hypoallergenic dog breeds (27,28). However, the possible different allergenicity of different dog breeds has been described (29)(30)(31). ...
Article
Allergen repertoire should reflect the region's climate, flora, and dining culture to allow for a better diagnosis. In Korea, tree pollens of oak and birch in the spring in conjunction with weed pollens of mugwort, ragweed, and Japanese hop are the main causes of seasonal allergic rhinitis. More specifically, the sawtooth oak in Korea and the Japanese hop in East Asia make a difference from western countries. Among food allergens, the sensitization to silkworm pupa and buckwheat is also common in Korean patients. Honey bee venom due to apitherapy in traditional medicine and Asian needle ant, Pachycondyla chinensis, are important causes of anaphylaxis in Korea. Climate change, frequent overseas traveling, and international product exchanges make situations more complicated. Ragweed, for example, was not native to Korea, but invaded the country in the early 1950s. Recently, Japanese hop and Asian needle ants have been recognized as important invasive ecosystem disturbing species in western countries. However, the molecular properties of the component allergens from these unique culprit allergens have been poorly characterized. The present review summarizes the molecular studies on the allergens of regional importance in Korea.
... 9 Can f 2 causes sensitization in around 25%. 10 Both these proteins are abundant in saliva, 6 but Can f 1 is also found in fur. 11 Can f 3, dog serum albumin, displays a high homology to other mammalian albumins. It is present in dog dander, saliva, and urine in addition to serum. ...
... 17 The amount and composition of allergens has been shown to differ between dogs, and the difference is greater between individuals than breeds. 11 Likewise, each patient displays a unique IgE profile and will thus respond to different combinations of dog allergens. This is a likely reason to why some individuals state that they react to certain dogs but not to others. ...
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Background Five to ten percent of the population in affluent countries are allergic to dog. Diagnosis and treatment is based on allergen extracts from natural sources where composition and concentration are poorly defined. Objective We aimed to quantify six dog allergens (Can f 1‐6) in commercial skin prick test (SPT) solutions and to determine individual allergen profiles in dogs. Method The allergen content of SPT solutions from five vendors and allergen source material from three anatomical sites were analyzed. Fur and saliva samples were collected from a mixed population of 120 dogs. Can f 1‐6 were quantified by inhibition ELISA using purified recombinant or natural allergens and polyclonal or monoclonal antibodies. Allergenicity was analyzed by basophil activation test. Results Extensive variation in allergen composition was observed in commercial SPT vials resulting in a patient‐dependent ability to activate basophils. Extract heterogeneity depended on collection site and allergen composition in individual dogs and source materials. Can f 2 and 6 exhibited low levels in fur and SPT solutions, whereas Can f 4, which was the dominating allergen in fur samples did not display similar high proportions in SPT solutions. Can f 3 varied most among SPT solutions. Conclusion There is a great variation of dog allergens in natural extracts raising questions of source, sampling, processing and ultimately of standardization and minimum allergen levels for accurate diagnosis and treatment. This article is protected by copyright. All rights reserved.
... 30 The amount of shedding and length of hair are thought to be protective since pet dander and saliva stick to hair and are not released into the environment, but studies find that there was no difference in the air or on the floor. 68 In a study measuring the level of allergen Can f 1 via enzyme-linked immunosorbent assay (ELISA) in breeds thought to be "hypoallergenic" (Labradoodle, Poodle, Spanish Water Dog, and Airedale Terrier) found levels in the hair and coat of dogs as well as floor and airborne dust to be similar to non-hypoallergic breeds (Labrador Retriever and a control group). 68 As many of these allergens are still being characterized with respect to their allergenicity, their true function in vivo in dogs and cats still remain unclear and inactivating all of them may have a detrimental impact on these animals. ...
... 68 In a study measuring the level of allergen Can f 1 via enzyme-linked immunosorbent assay (ELISA) in breeds thought to be "hypoallergenic" (Labradoodle, Poodle, Spanish Water Dog, and Airedale Terrier) found levels in the hair and coat of dogs as well as floor and airborne dust to be similar to non-hypoallergic breeds (Labrador Retriever and a control group). 68 As many of these allergens are still being characterized with respect to their allergenicity, their true function in vivo in dogs and cats still remain unclear and inactivating all of them may have a detrimental impact on these animals. ...
Article
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Allergies to dogs and cats affect 10%-20% of the population worldwide and is a growing public health concern as these rates increase. Given the prevalence of detectable dog and cat allergens even in households without pets, there is a critical need to accurately diagnose and treat patients to reduce morbidity and mortality from exposure. The ability to diagnose cat sensitization is good, in contrast to dogs. Component resolved diagnostics of sensitization to individual allergenic proteins will dramatically improve diagnosis. This review focuses on the current state of knowledge regarding allergies to dogs and cats, recent advances, therapies such as subcutaneous immunotherapy, and discusses important areas to improve diagnosis and therapy. © The Korean Academy of Asthma, Allergy and Clinical Immunology • The Korean Academy of Pediatric Allergy and Respiratory Disease.
... Some breeds of cats (e.g., Siberian cat) have shown lower lever of Fel d 1, but no subsequent lower airborne dispersion of Fel d 1 within the domestic setting has been shown (30). Similarly, as shown in a recent study, no evidence support the classification of certain dog breeds (e.g., Labradoodle, Poodle, Spanish Waterdog, Airedale terrier) as "hypoallergenic" (73). Investigators compared the levels of Can f 1 in hair samples and in the indoor environment of hypoallergenic and non-hypoallergenic breeds and found no differences in Can f 1 levels in the homes of the two groups (73). ...
... Similarly, as shown in a recent study, no evidence support the classification of certain dog breeds (e.g., Labradoodle, Poodle, Spanish Waterdog, Airedale terrier) as "hypoallergenic" (73). Investigators compared the levels of Can f 1 in hair samples and in the indoor environment of hypoallergenic and non-hypoallergenic breeds and found no differences in Can f 1 levels in the homes of the two groups (73). ...
Article
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Allergic asthma is the most frequent disease among the chronic respiratory disorders in pediatric age with an important social impact. In the last years, many efforts have been made to identify effective preventive approaches to get a better control of symptoms and to obtain the best future outcomes for the patients. In patients with allergic asthma triggered by the exposure to indoor allergens, the avoidance is the first intervention to prevent the appearance or the worsening of bronchial symptoms. This review article summarized the most recent evidence from literature about the efficacy of specific control interventions for the most important allergens. Even if a wide spectrum of interventions has been suggested and may help to reduce exposure to trigger allergy for sensitized patients suffering from respiratory allergy, evidence supporting the efficacy of these approaches is still weak and subject of controversy. However, the exposure control to specific airborne allergens is still widely recommended and may be effective as part of a holistic approach to reduce the severity of allergic respiratory symptoms in sensitized individuals.
... In addition, allergen loads shed by an individual animal can vary enormously. Variations in allergen content of hair up to four orders of magnitude were observed in dogs 22) , horses 13,23) , and cattle 24) of different breeds and sexes. Another factor that could influence the high variability of allergen levels was talking during dust collection, which was not restricted as in other studies 8) . ...
Article
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Objectives: In this study, we applied novel nasal filters to assess animal allergen exposure of veterinary staff during their normal daily routine. Methods: Rhinix nasal filters were worn during work by 94 employees at different veterinary practices and 18 employees at a research institute, who acted as controls representing an animal-free environment. Contact with animals and the activities performed were documented by the study participants using a short questionnaire. Major allergens of cats (Fel d 1), dogs (Can f 1), and domestic mites (DM) were measured using fluorescence enzyme immunoassays. Results: At the practices, Can f 1 was detected in 98%, Fel d 1 in 82%, and DM allergens in 39% of the samples. Allergens were also detected in some control samples (6% for Can f 1, 39% for Fel d 1, and 17% for DM) but in very low concentrations. There was a highly significant difference between allergen levels in veterinary workers who treated at least one cat or dog during the sampling period and those who did not (2.66 vs. 0.70 ng/filter for Can f 1 and 1.01 vs. 0.20 ng/filter for Fel d 1). The amount of sampled Fel d 1 increased significantly with increasing duration of contact with cats. This effect was not observed for Can f 1. Conclusions: The majority of veterinary workers are exposed to dog and cat allergens, even without direct contact with these animals. Rhinix nasal filters may be considered a simple and easily applicable method for monitoring personal allergen exposure.
... Involving inappropriately termed hypoallergenic animals, such as labradoodles, does not provide an allergen-free environment (36). Moreover, Vredegoor et al. (106) found that Can f 1 in the hair and coat, a component that counts for at least half of the allergenic activity, was higher in these dogs than in control breeds such as Labrador retrievers. From a welfare aspect, the allergological risks of implementing CAIs in a hospital or outpatient setting should not be underestimated (36). ...
Article
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CAIs (canine-assisted interventions) include “canine-assisted therapy” in which a therapist sets client-oriented goals, ’canine-assisted activities’ with recreational goals for clients, and ’canine-assisted education/learning’ in which teachers or coaches create learning goals for students or clients. CAIs vary in nearly every way; their only common trait is the involvement of dogs to respond to human need. However, the benefits of involving dogs are highly dependent on the animal’s health and behavior. A dog exhibiting negative behavior or an unwell dog might pose a risk, especially for CAI target groups, specifically individuals with immunosuppression, chronic illness, children, elderly, etc. Therefore, positive animal welfare as preventative medicine to avoid incidents or transmission of zoonosis is an attractive hypothesis, with implications for human and animal, health and well-being. This review aims to summarize the current published knowledge regarding different aspects of welfare in CAIs and to discuss their relevance in the light of health and safety in CAI participants. As method for this study, a literature search was conducted (2001–2022) using the Prisma method, describing issues of dog welfare as defined in the Welfare Quality® approach. This welfare assessment tool includes 4 categories related to behavior, health, management, and environment; it was, therefore, applicable to CAIs. Results indicate that dogs working in CAIs are required to cope with diverse variables that can jeopardize their welfare. In conclusion, we propose regular welfare assessments for dogs in CAIs, which would also protect the quality of the CAI sessions and the clients’ safety and well-being.
... In consultation with the FVM and based on the literature (Vredegoor et al., 2012), an 8-week-old Australian Labradoodle puppy was privately purchased from an experienced (10+ years) breeder. This breed was chosen based on its friendly and sociable disposition, high trainability, and low to no shedding quality. ...
Article
Universities are places to promote the wellbeing of people who learn, work, and live within them. This article reports on an innovative, holistic, and embedded wellness dog program that was developed by the Faculty of Nursing to support the wellbeing of students, faculty, and staff. The innovation included a collaborative partnership between two faculties (the faculties of Veterinary Medicine and Nursing), and the targeted purchase, training, and socialization of a wellness dog. Pet wellness programs have the potential to be an important mental health intervention on university campuses. While the program was postponed due to COVID-19, the purpose of this article is to share processes used to create the wellness dog program, with suggestions regarding implementation and evaluation.
... However, published data revealed that the levels of allergen Can f 1 in the hair and coat of dogs as well as floor and airborne dust were comparable between breeds thought to be "hypoallergenic" (Labradoodle, Poodle, Spanish Water Dog, and Airedale Terrier) and those considered nonhypoallergenic. 111 Molecular-based allergy diagnostics would help in determining primary sensitization to dog allergens and overcome the problem of crossreactivity. Since dog allergic individuals are not all exclusively allergic to Can f 1, combinations of the appropriate component allergens will be required for optimal therapeutic interventions. ...
Article
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Allergen exposure may exacerbate asthma symptoms in sensitized patients. Allergen reduction or avoidance measures have been widely utilized; however, there is ongoing controversy on the effectiveness of specific allergen control measures in the management of children with asthma. Often, allergen avoidance strategies are not recommended by guidelines because they can be complex or burdensome, although individual patients may benefit. Here we explore the potential for intervention against exposure to the major allergens implicated in asthma (ie, house dust mites, indoor molds, rodents, cockroaches, furry pets, and outdoor molds and pollens), and subsequent effects on asthma symptoms. We critically assess the available evidence regarding the clinical benefits of specific environmental control measures for each allergen. Finally, we underscore the need for standardized and multifaceted approaches in research and real-life settings, which would result in the identification of more personalized and beneficial prevention strategies.
... Pandemic Puppy owners were more likely to be first-time dog owners with children in their household, often with children aged 5-10 years of age, who sought a breed/crossbreed that would fulfil lifestyle factors such as being a suitable size for their lifestyle, good with children, easy to train and hypoallergenic [1]. The belief that designer crossbreeds are 'hypoallergenic' is a popular misconception [71], and could potentially lead to unmet owner expectations and allergies if the crossbreed was explicitly selected for this reason. ...
Article
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The UK recorded sharp rises in puppy purchasing during the 2020 phase of the COVID-19 pandemic, with many first-time dog owners purchasing puppies to improve their mental health during this challenging period. Government restrictions on movement and social interaction during the pandemic led to animal welfare concerns over puppies’ reduced time-sensitive exposures to key environmental and social stimuli during their critical developmental period. This study aimed to compare demographics, health and early-life experiences of puppies purchased and brought home < 16 weeks of age between 23 March–31 December 2020 (“Pandemic Puppies”), with dogs purchased and brought home < 16 weeks during the same date period in 2019 (“2019 puppies”). An online survey of UK-based puppy owners was conducted between 10 November and 31 December 2020 with valid responses representing 5517 puppies (Pandemic Puppies: n = 4369; 2019 puppies: n = 1148). Multivariable logistic regression modelling revealed that Pandemic Puppies were less likely to have attended puppy training classes (67.9% 2019 vs. 28.9% 2020; p < 0.001) or had visitors to their home (94.5% 2019 vs. 81.8% 2020; p < 0.001) aged < 16 weeks compared with 2019 puppies. Fewer Pandemic Puppies underwent veterinary checks prior to purchase than 2019 puppies (2019: 91.3% vs. 2020: 87.4%; p < 0.001), but more were sold with a passport (2019: 4.1% vs. 2020: 7.1%; p < 0.001). Pandemic Puppies were significantly more likely to be ‘Designer Crossbreeds’ (2019: 18.8% vs. 2020: 26.1%; p < 0.001) and less likely to be Kennel Club registered than 2019 puppies (2019: 58.2% vs. 2020: 46.2%; p < 0.001). Greater support from veterinary and animal behavioural professionals is likely needed to ameliorate the health and behavioural impacts of growing up in a pandemic upon this vulnerable population.
... Preliminary studies exposing cat-allergic subjects to animals showed few symptoms, although no allergen measurements were published. Further information is required to understand the clinical responses of cat-allergic individuals to these animals, both with short-term and prolonged exposure (Vredegoor et al, 2012). ...
... Anecdotal reports suggest that working with dogs who shed less or have compact coats such as Labradoodle, Poodle, Spanish Waterdog, or Airedale terrier could result in fewer reactions. However, Vredegoor et al. (2012) found that Can f 1 in the hair and coat, a component that counts for at least half of the allergenic activity (de Groot et al., 1991), was higher in so-called hypoallergenic dogs than in control breeds such as Labrador retrievers. These results suggest that it is hard to talk about hypoallergenic dogs. ...
Article
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Although animal-assisted interventions (AAIs) share specific characteristics, their differences can be quite significant (Lajoie, 2003). Most research on AAIs focuses on the human side (Muñoz Lasa et al., 2011). The autonomy and well-being of the animals involved are seldom studied, as well as the possible values of conflict between humans and animals (Glenk, 2017). The COVID-19 pandemic that gripped the world starting in 2019–2020, greatly affected human-animal interaction projects, such as animal-assisted interventions (Kumar et al., 2020). To control the spread of the SARS-CoV-2 virus, several (inter)national organisations, came up with new safety protocols. We focus on scientific insights and anecdotal observations, as well as the ethical implications of the COVID-19 safety protocols on AAIs in Belgium and Italy. The paper aims to give the reader an insight into the complexity of AAIs and its future relevance for developing protocols to handle the current and maybe future pandemics. https://brill.com/view/journals/jaae/aop/article-10.1163-25889567-BJA10019/article-10.1163-25889567-BJA10019.xml
... Popular literature considers a number of dog breeds to be hypoallergenic, such as the labradoodle, poodle, and Airedale terrier. However, there is a lack of evidence proving the existence of such breeds [36]. Therefore, so-called hypoallergenicity would have no influence on the amount or presence of recovered CFUs, which indeed it did not. ...
Article
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(1) Background: People with disabilities may benefit from an assistance dog (AD). Despite regulations that prohibit the denial of ADs to public places, this still occurs on a regular basis. The main argument for denial of access is that dogs compromise hygiene with their presence, which could cause a health hazard. Meanwhile, people are allowed to walk into and out of public places freely. (2) Objective: As a pilot study, to investigate the number of Enterobacteriaceae and the presence of Clostridium difficile bacteria on the paws of ADs and pet dogs (PDs) as well as the shoe soles of their users and owners. With the results, an assessment can be made as to whether measures are required to reduce environmental contamination (e.g., in hospitals). (3) Methods: In total, 25 ADs, 25 PDs, and their 50 users/owners participated in the study. Each participant walked their dog for 15–30 min prior to the sampling of the front paws. Each PD owner or AD user filled out a general questionnaire about the care of their dogs, and AD users were asked to fill out an additional questionnaire on their experiences regarding the admittance of their ADs to public places (in particular, hospitals). Dutch hospitals were questioned on their protocols regarding the admittance of ADs and their visitor numbers, including the percentage of AD users, to put these numbers into perspective. (4) Results: Dog paws were more often negative for Enterobacteriaceae compared to shoe soles (72% and 42%, respectively) and also had significantly lower bacterial counts (mean of 3.54log10 and 5.03log10 colony-forming units (CFUs), respectively; p < 0.05). This was most distinct in the comparison between PDs and their owners (3.75log10 and 5.25log10 CFUs; p < 0.05); the numbers were similar between ADs and their users (3.09log10 and 4.58log10 CFUs; p = 0.2). C. difficile was found on one (4%) AD user’s shoe soles. Moreover, 81% of AD users had been denied access with their current AD once or several times, the main reason being hygiene. The results of the visibly and invisibly disabled were significantly different. The number of AD users as opposed to the total number of hospital visitors was 0.03% in one hospital and is estimated to be 0.02% in the Netherlands. (5) Conclusions: The general hygiene of dogs’ paws is far better than that of shoe soles, mostly demonstrated by the better general hygiene of PD paws compared with their owners’ shoe soles; ADs and their users had comparable levels of general hygiene. In addition, the number of AD users amongst the total number of hospital visitors in the Netherlands is very limited. Thus, hygiene measures to reduce any contamination due to dog paws do not seem necessary.
... Однако при этом сохраняется воздействие аллергенов, содержащихся, например, в слюне. Более того, существенных различий между уровнями аллергенов в окружающей среде при содержании «обычных» животных по сравнению с т. н. гипоаллергенными не обнаружено [27,55,71]. Не удалось вывести гипоаллергенных кошек и в результате модификации генов [72]. ...
Article
The prevalence of allergies to domestic animals increases due to the increase in the number of pets worldwide, followed by serious medical and social problems. Domestic cat (Felis domesticus) is one of the most common pets and one of the most frequent (after dust mite) source of indoor allergens and risk factor for bronchial asthma and allergic rhinitis. This review collects relevant information on the issues of hypersensitivity to cat allergens (the term «cat allergy» will be used later). The authors consider issues of diagnosis, treatment and prevention of this condition. Special attention is given to the management of patients with cat allergies and particularly usage of special nutrition for cats that can reduce the level of the main cat allergen Fel d 1 in the environment. Whereas, this leads to decrease of allergic diseases symptoms severity.
... The desirability of non-shedding dogs is exemplified in the international population boom in 'designer cross breeds' that include Poodle genetics (e.g. Labradoodle, Cockapoo) [62], with such crosses being marketed as low-shedding and hypoallergenic, despite limited evidence for reduced allergen production by these dogs [63]. Negative impacts of health problems upon owner lifestyle included increased and abnormal respiratory noise, particularly snoring, interruption of owner sleep or annoyance during the day. ...
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Brachycephalic breeds are proliferating internationally, with dramatic rises in popularity juxtaposed with common and severe breed-related health problems. Physical appearance is as a dominant factor attracting owners to brachycephalic breeds; however, whether these owners will choose their current breed for future ownership and develop ‘breed-loyalty’ in the face of health problems is not yet known. The aims of this study were (1) to quantify levels of, and explore factors associated with, brachycephalic dog owners’ intentions to: (i) reacquire and/or (ii) recommend their current breed to potential first-time dog owners, and (2) to use qualitative methods to explore why brachycephalic dog owners would or would not recommend their current breed. This large mixed methods study reports on 2168 owners of brachycephalic breeds (Pugs: n = 789; French Bulldog: n = 741; Bulldogs: n = 638). Owners were highly likely to want to own their breed again in the future (93.0%) and recommend their breed to other owners (65.5%). Statistical modelling identified that first-time ownership and increased strength of the dog-owner relationship increased the likelihood of reacquisition and/or recommendation. In contrast, an increased number of health problems, positive perception of their dog’s health compared with the rest of their breed, and dog behaviour being worse than expected decreased the likelihood of reacquisition and/or recommendation. Thematic analyses constructed three themes describing why owners recommend their breed: positive behavioural attributes for a companion dog, breed suited to a sedentary lifestyle with limited space, and suitability for households with children. Five themes described why owners recommended against their breed: high prevalence of health problems, expense of ownership, ethical and welfare issues associated with breeding brachycephalic dogs, negative effects upon owner lifestyle and negative behavioural attributes. Understanding how breed-loyalty develops, and whether it can be attenuated, will be key to controlling the current population boom in brachycephalic breeds in the long-term.
... In summary, this study demonstrates the heterogeneity of the raw materialused for producing dog extract.In case of urine, this is the first article showing the individual differences of the allergenic profile in male-dog urine extracts of the same breed and similar age. On the other hand, the variability of dog fur, saliva and hair extracts has been previously demonstrated, revealing significant variationson most of dog allergens regardless of breed [2,11].Additionally, and from a clinical point of view, our results also confirmedthe variability of the allergenic profile of individuals. According to that, and in order to guaranty the clinical efficacy of diagnostics and immunotherapy, it seems clear that dog extracts must be prepared according to the allergenic profiles of patients. ...
... 38 It must be underlined, however, that no statistically significant conclusions pertaining to the presumed hypoallergenic nature have been drawn for any breeds. 39 Are special types of bedding worth recommending? As with HDM, attempts are made at animal-produced allergen avoidance by using barrier duvet and pillow covers with pores smaller than 6 m. ...
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Asthma and other inhaled allergies are some of the most common paediatric diseases. The association of exposure to allergens with induction and exacerbation of symptoms has been proven. The majority of allergens are permanently or periodically suspended in the air, which leads to impaired quality of life for sensitive patients. Therefore, many methods of prevention and therapy of allergic diseases have been developed. The method of allergen exposure avoidance is often the first and the most significant measure. The present research has been conducted to evaluate, based on scientific data, which measures have the most reliable evidence of effectiveness. Environmental allergen avoidance methods, despite limited evidence supporting their clinical efficacy, are listed as the main therapeutic approaches in most recommendations. The significance of the holistic approach is also emphasised: only simultaneous introduction of several avoidance methods can bring possibly beneficial effects for the patient.
... • A "hypoallergic dog" labelling is controversial, because different measurements are cited. Data exist on concentrations in reservoir dust and airborne allergen levels in the homes of dog owners, whereas other data focus on concentrations of allergens in samples from the fur (Vredegoor, Willemse, Chapman, Heederik, & Krop, 2012) or in the saliva (Breitenbuecher et al., 2016;Polovic et al., 2013). ...
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Background: Dog-assisted therapy in the dental clinic may be an attractive alternative to sedation for anxious patients. Including a dental therapy dog in a clinical setting introduces new hazards and potential risks to health and safety for both humans and animal. Objectives: The study aims to describe potential hazards associated with risks to humans by having a therapy dog present in the dental clinic and to provide guidance on best practices to minimise and control risks for the patients, the dentist, and the dental clinic staff. Materials and methods: Literature searches in Medline, http://Clinicaltrials.gov, and Google Scholar for qualitative and quantitative assessments of hazards and risks associated with the use of therapy dogs in health care settings, in combination with a review of the reference list of the included studies. Identified hazards and risks were analysed with respect for the health and welfare of humans in a dental clinic setting that involves the presence of a therapy dog. Results: Potential risks to health and safety for humans in dental clinics that offer dog-assisted therapy can be categorised within four general categories of hazards: the dog as a source of zoonotic pathogens and human diseases, exposure to canine allergens, adverse animal behaviour, and dangers associated with high activity in a congested dental clinic operatory. Risks to humans are reduced by maintaining awareness amongst the dental clinic staff and the dog handler of all potential hazards in the dental clinic, and on how to reduce these hazards as well as adverse events that may scare the dental therapy dog. Conclusions: Risks to the health and safety of humans in the presence of therapy dog in the clinics are present but are low if the dental clinical staff and dog handlers comply with best practices.
... However, even if there is no dog in a person's house, canine allergens can also be found in schools and other public places as they can be carried on clothes, making them almost impossible to avoid. canine allergens can cause symptoms ranging from rhinoconjunctivitis to severe asthma attacks (4,5). In one large study conducted in a European population, 27% of people with suspected allergic disease had a positive skin prick test when exposed to canine extract (6). ...
Article
Dogs are a major source of indoor allergens. However, the prevalence of dog allergies in China remains unclear, especially in children. In the present study, Can f 7, a canine allergen belonging to the Niemann pick type C2 protein family, was selected to study its sensitization rate in Chinese children with dog allergies. The Can f 7 gene was subcloned into a pET-28a vector and expressed in Escherichia coli BL21 (DE3) cells. Recombinant Can f 7 was purified by nickel affinity chromatography, identified by SDS-PAGE electrophoresis, and had its allergenicity assessed by western blot, ELISA and basophil activation tests. Through a series of bioinformatical approaches, B-cell epitopes, secondary structures, and 3 dimensional (3D) homology modeling of Can f 7 were predicted. The activity of the B cell epitopes was verified by ELISA. The recombinant Can f 7 showed a distinct band with a molecular weight of 14 kDa. Six of 20 sera from dog-allergic children reacted positively to the Can f 7. Can f 7 induced an ∼4.0-fold increase in cluster of differentiation 63 and C-C motif chemokine receptor R3 expression in basophils sensitized with the serum of dog-allergic children compared with those of non-allergic controls. The secondary structure analysis showed that Can f 7 contains 6 β-sheets. Five B cell epitopes of Can f 7 were predicted, and two of these were confirmed by ELISA. These results indicate that Can f 7 is an important canine allergen in Chinese children and provide novel data for further research concerning the use of Can f 7 in the diagnosis and treatment of Chinese children with canine allergy symptoms.
... We did not see a clear association of exposure to "hypoallergenic" dogs with risk of asthma, but with an increased risk of allergy. Previous studies have not shown differences among dog breed groups in allergen shedding 16,17 , and we speculate that the association is confounded by parental allergy to furry animals, which increases the risk of allergy in their children and thus the likelihood of acquiring a "hypoallergenic" dog 7 . We were only able to adjust for parental allergy medication, but not the type of allergy, which could explain the remaining association after accounting for parental allergy. ...
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There is observational evidence that children exposed to dogs in early life are at lower risk of asthma. It is unknown whether this association is modified by dog characteristics such as sex, breed, number of dogs, and dog size. The aim of this study was to determine whether different dog characteristics modify the risk of asthma among children exposed to dogs during their first year of life. In the main analysis, we used national register data for all children born in Sweden from Jan 1st 2001 to Dec 31st 2004 with a registered dog in the household during their first year of life (n = 23,585). We used logistic regression models to study the association between dog characteristics and the risk of asthma or allergy diagnosis and medication at age six. The prevalence of asthma at age six was 5.4%. Children exposed to female dogs had lower risk of asthma compared to those exposed to male dogs, odds ratio, OR = 0.84 (95% confidence interval, CI 0.74 to 0.95). Children with two dogs or more had lower risk of asthma than those with one dog only, OR = 0.79 (95% CI 0.65 to 0.95). Children whose parents had asthma and allergy had a higher frequency of exposure to dog breeds anecdotally described as “hypoallergenic” compared to those parents without asthma or allergy (11.7% vs 7.6%, p < 0.001). Exposure to these breeds were associated with higher risk of allergy OR = 1.27 (95% CI 1.02 to 1.59) but not asthma. In conclusion, we found evidence of an association between the sex of dog and the number of dogs with a lower risk of childhood asthma in dog-exposed children.
... Понимание многомерности сенсибилизации к ингаляционным аллергенам млекопитающих позволяет критично рассмотреть возможность существования гипоаллергенных животных («гипоаллергенная кошка», «гипоаллергенная собака»). Так, уровень Can f 1 в образцах шерсти собак «гипоаллергенных» пород не ниже, чем у «негипоаллергенных» пород (лабрадор, пудель, эрдельтерьер, испанская водяная и т.д.) [19]. Необходимо подчеркнуть, что возможность создания гипоаллергенных пород является коммерчески направленным проектом, который не имеет ничего общего с реальными проблемами больных. ...
... It has been suggested that dog or cat allergies do not differ by breed, and that socalled hypoallergenic pets have higher allergen levels in hair and environmental samples. 40 Instead, gender, age, and spay/ neuter status, as suggested previously, influence glandular secretion and resulting allergenicity. 41 Major pet allergens, such as Can f 1 (from dogs) and Fel d 1 (from cats), generally originate from salivary, sebaceous, or perianal glands, with the skin and hair serving as reservoirs, and their production may be influenced by sexual hormones, such as testosterone. ...
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Purpose: This study evaluated dog and cat allergies and their association with allergen avoidance measures in Korean adults. Methods: The study population consisted of 537 adults who currently kept dogs or cats and participated in a pet exhibition in Korea. The subjects were asked to complete questionnaires regarding pet ownership, allergen avoidance, and allergy symptoms, and underwent skin prick tests. They were considered to have a dog or cat allergy if they suffered from one or more of allergy symptoms during contact with their pets. Results: In total, 103 of 407 dog owners (25.3%) and 45 of 130 cat owners (34.6%) had a dog or cat allergy, respectively. Dog owners kept 1.3±1.5 dogs; this number did not differ according to the presence of dog allergy. Dog owners with a dog allergy had owned their dogs longer than those without (88.0±72.0 vs 67.5±72.7 months, P<0.05). Cat owners kept 2.1±3.6 cats; this number did not differ according to the presence of cat allergy, nor did the duration of cat ownership. Cat owners with a cat allergy had facial contact and slept with their cats less frequently (8.6±11.9 vs 18.3±27.0 times/day, P<0.01; 71.1% vs 81.2%, P<0.05); however, they had their cats shaved and beds cleaned less frequently than those without (1.8±3.3 vs 3.2±4.4 times/year, P<0.05; 1.5±1.5 vs 3.9±6.0 times/month, P<0.01). Conclusions: Cat owners with a cat allergy tried to minimize contact with their cats, but efforts to avoid indoor cat allergens were lower than those without. In comparison, dog owners with a dog allergy had kept their dogs for longer time than those without; however, current contact with their dogs and allergen avoidance measures did not differ between the 2 groups.
... 106 Certain dog breeds are promoted as hypoallergenic breeds, such as the Labradoodle, Poodle, Spanish Waterdog, and Airedale terrier. 107,108 Recent studies were performed comparing the amount of Can r1 and r2, an antigen released by dogs, found that these proteins were significantly higher in breeds promoted as hypoallergenic. 107,109 The amount of protein was nearly double in these "hypoallergenic" breeds as compared to ones classified as allergenic. ...
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Many health care providers are concerned with the role environmental exposures play in the development of respiratory disease. While most individuals understand that outdoor air quality is important to their health status, many are unaware of the detrimental effects indoor air pollution can potentially have on them. The Environmental Protection Agency (EPA) regulates both outdoor and indoor air quality. According to the EPA, indoor levels of pollutants may be up to 100 times higher than outdoor pollutant levels and have been ranked among the top 5 environmental risks to the public. There has been a strong correlation between air quality and health, which is why it is crucial to obtain a complete environmental exposure history from a patient. This article focuses on the effects indoor air quality has on the respiratory system. Specifically, this article will address secondhand smoke, radon, carbon monoxide, nitrogen dioxide, formaldehyde, house cleaning agents, indoor mold, animal dander, and dust mites. These are common agents that may lead to hazardous exposures among individuals living in the United States. It is important for health care providers to be educated on the potential risks of indoor air pollution and the effects it may have on patient outcomes. Health problems resulting from poor indoor air quality are not easily recognized and may affect a patient’s health years after the onset of exposure.
... The size distribution of particles associated with Can f 1 is similar to that of Fel d 1 [60••]. A wide variability in Can f 1 levels can be found between dog breeds, but there is no evidence for a hypoallergenic breed [61,62]. Can f 5 is also considered a major allergen, with up to 70 % of dogallergic patients having Can f 5-specific IgE. ...
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Purpose of review The purpose of this review is to evaluate the most recent findings on indoor allergens and their impact on allergic diseases. Recent findings Indoor allergens are present inside buildings (home, work environment, school), and given the chronic nature of the exposures, indoor allergies tend to be associated with the development of asthma. The most common indoor allergens are derived from dust mites, cockroaches, mammals (including wild rodents and pets), and fungi. The advent of molecular biology and proteomics has led to the identification, cloning, and expression of new indoor allergens, which have facilitated research to elucidate their role in allergic diseases. This review is an update on new allergens and their molecular features, together with the most recent reports on their avoidance for allergy prevention and their use for diagnosis and treatment. Summary Research progress on indoor allergens will result in the development of new diagnostic tools and design of coherent strategies for immunotherapy.
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“Designer dogs”, which are the hybrid offspring that result from intentionally breeding dogs belonging to different breeds, are an extremely popular pet choice in the United States. Poodle mixes, often called “doodles”, are a very common type of designer dog. However, there are many misconceptions surrounding them, and the reality of owning one may not match the owner’s expectations. For instance, many people believe these dogs to be non-shedding and hypoallergenic, although this is not always the case. This study explored whether the reality of owning a doodle matches owner expectations. For comparison purposes, we also asked owners of non-doodle dogs about their expectations versus reality. Our survey-based study included 2191 owners of doodles and non-doodle dogs recruited via groups of dog owners on Facebook and Reddit. The data showed that, when selecting their dogs, doodle owners were more influenced than non-doodle owners by their dog’s appearance and by the perception that doodles are good with children and are generally healthy. Doodle owners reported being highly satisfied with their dogs; nevertheless, more than twice as many doodle owners than owners of the other groups of dogs reported that their dog’s maintenance requirements, such as their need for regular grooming, were more intensive than they had expected. This finding suggests that those interested in owning doodles would benefit from having more information about their dog’s grooming needs so they can decide whether they have the time and money required to meet their dog’s welfare needs.
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AID Alerjik Rinit Rehberi 2022
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Background: Demand for intentional crosses of purebred dog breeds, often labelled 'designer crossbreeds' (e.g., Labrador Retriever X Poodle, the 'Labradoodle'), has recently increased in the UK. This study aimed to explore this phenomenon by comparing pre-purchase motivations, pre-purchase and purchase behaviours of UK owners of designer crossbred puppies purchased during 2019-2020 with those of owners of purebred puppies purchased during the same period. Results: Data were collected in an online cross-sectional survey between November-December 2020. Responses from n = 6293 puppies (designer crossbred puppies: n = 1575; purebred puppies: n = 4718) were analysed. Perceived hypoallergenicity was cited as a motivator for breed/crossbreed choice by almost half of designer crossbreed owners (47.1%), six times more than purebred dog owners (7.86%; odds ratio [OR]: 9.12, 95% CI: 7.70-10.8). Designer crossbred puppies were more likely to have been acquired via a general selling website (e.g., Gumtree; 13.8%) compared to purebred puppies (7.67%; OR: 2.19, 95% CI: 1.77-2.71), or an animal-specific selling websites (e.g., Pets4Homes; 55.7%) compared to purebred puppies (37.4%; OR: 1.89, 95% CI: 1.65-2.17). Designer crossbreed owners were less likely to see their puppy in person prior to purchase than purebred owners (60.4% vs. 67.0%, respectively; OR: 0.74, 95% CI: 0.64-0.85), and at purchase, designer crossbred puppies were less likely to be seen with their mother (73.1% vs. 79.8%, respectively; OR: 0.82, 95% CI: 0.70-0.95), and littermates (67.7% vs. 78.1%, respectively; OR: 0.63, 95% CI: 0.55-0.73). Designer crossbreeds had a significantly higher purchase price, with 25.7% of designer crossbreed puppies costing £2000-£2999 compared to 15.1% of purebred puppies (X2 = 207.31, p < 0.001). Conclusions: The recent boom in designer crossbreeds in the UK has been fuelled by a desire for perceived hypoallergenic and generally healthy dogs that fit the lifestyles of households with children and limited experience with dogs. Some sought-after traits in designer crossbreeds are misconceptions that risk canine welfare, including relinquishment risk, if owner expectations are not met. Purchasing practices fuelling this boom support irresponsible breeding and selling practices, which combined with reduced pressure for health testing from buyers, may result in a higher disease burden and poorer future welfare for this growing designer dog population.
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Objective: In recent decades, many indoor allergens have been identified, including dust mite, cat, dog, mouse, cockroach and indoor molds, which have important health effects particularly in sensitized asthmatics. This review aims to update our understanding regarding the extent of these exposures in the indoor environment, review strategies for reducing their levels in the environment, and highlight innovative recent trials targeting these exposures and their impact on pediatric asthma morbidity. Data Sources: Recent practice parameter updates on indoor allergen exposures, seminal studies, and recent peer-reviewed journal articles are referenced. Study Selections: This review cites recent cohort studies of well-characterized pediatric asthmatic patients as well as innovative randomized controlled trials evaluating exposure to environmental allergens, interventions to limit these exposures, and their outcomes. Results: Links between indoor aeroallergen exposures and health outcomes have been well established. However, only some allergen reduction interventions have been successful in improving health outcomes. Conclusion: There are many complicating factors involved in allergic exposures and health outcomes. The interplay between patient genetic factors, indoor allergic triggers, airborne irritants/pollutants and microbial exposures complicate the study of indoor allergen exposures and their impact on asthma morbidity.
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Exposure to dog allergens is almost impossible to avoid, as dogs are part of our society and frequently encountered both outdoors and indoors. This poses problems to individuals allergic to dogs, a common condition with reported sensitization rates around 20% 1. It is therefore crucial to increase our understanding on how dog allergens spread in the environment and on exposure by inhalation.
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Bronchial asthma is one of the most common allergic diseases. To improve bronchial asthma, an "environmental adjustment" is commonly recommended, to reduce the amount of inhaled allergens. However, there is insufficient evidence to support such a recommendation. The following two points are central to the question of whether adjusting the environment can improve bronchial asthma: (1) It is necessary to examine 'Whether the environment is contaminated with the allergen that causes asthma'. A meta-analysis has shown that there are a number of cases where environmental recommendations were not effective for all sensitized families. However, there is no convenient method to examine the allergen concentration to which a person is exposed from day to day. (2) Allergen levels should be reduced to a level that does not aggravate disease. Adjusting a subject's environment has proven to be complex, usually requiring a multifactorial approach. However, performing and maintaining multiple methods simultaneously is challenging.We believe that these points require further investigation in order to improve environmental adjustments.
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Allergic rhinitis is an IgE-mediated immune reaction of the nasal mucosa to foreign substances (allergens) characterized by sneezing, nasal congestion, rhinorrhea, and nasal itching often accompanied by red, watery, itchy eyes, thus the term rhinoconjunctivitis. For these symptoms to occur, various key pathophysiologic responses must be present and will be described briefly. Initially, the nasal mucosa is exposed to an allergen of which there are many varieties. The allergen is processed by antigen-presenting cells (such as macrophages, dendritic cells, and Langerhans cells), and portions of it are then presented to helper T cells as well as class II MHC molecules [1,2]. Helper T cells then secrete cytokines promoting growth and differentiation of other immune cells involved in the allergic response. The helper T cells are of the TH2 CD4+ variety and are responsible for secretion of cytokines such as IL-4, IL-5, and IL-13 [3]. IL-4 and IL-13 are key molecules involved in the upregulation of production of allergen-specific IgE by plasma cells, and IL-5 is important in the recruitment and survival of eosinophils, key cells in the allergic response [3–5]. Allergen-specific IgE attaches to high-affinity receptors on mast calls and basophils as well as low-affinity receptors on other cell types creating a sensitized nasal mucosa [6].
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Atopic dermatitis, or eczema, is chronic inflammatory pruritic skin disorder, affecting both children and adults. Patients with atopic dermatitis often experience sleep disturbance, especially during flares of their skin disease. Sleep disturbances in atopic dermatitis range from difficulty falling asleep, shorter sleep duration, nighttime awakenings, and daytime sleepiness and fatigue. In addition, atopic dermatitis has also been associated with parasomnias and sleep-related breathing disorders. In children with atopic dermatitis, sleep disturbance may extend from the child to adult caregiver. The effects of sleep disruption in this setting are widespread including increased risk of mood disorders, impaired ability to perform activities of daily living, and decreased quality of life.
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Background Horses are an important source of allergens, but the distribution of horse allergens is poorly understood. Five horse allergens have been identified, Equ c 1‐4 and 6. Equ c 4 seems to be an important allergen, with an IgE‐binding frequency of 77% in horse‐sensitized individuals. Objectives The aim of this study was to investigate levels of horse allergen Equ c 4 in dander, saliva and urine from ten horse breeds. Method: The study population included 170 horses (87 mares, 27 stallions, 56 geldings) from ten breeds. Horse dander, saliva and urine samples were collected. Levels of horse allergen Equ c 4 were quantified using a two‐site sandwich ELISA (mAb 103 and 14G4) and were expressed as Equ c 4 U/μg protein. Results The horse allergen Equ c 4 was present in all dander and saliva samples from ten horse breeds, with high within‐breed and inter‐breed variations; GM values were 639 Equ c 4 U /μg protein (range 5 – 15264) for dander and 39.5 (4 – 263) for saliva. Equ c 4 was found in 19/21 urine samples. Adjusted for age, sex and changes over time, no differences between breeds could be seen in dander, while in saliva the North Swedish horse showed lower levels of Equ c 4 than any other breed. The levels of Equ c 4 protein in dander and saliva were significantly higher in samples from stallions compared to mares and geldings, independent of breed. Conclusions & Clinical Relevance The results show a high variability in allergen levels of Equ c 4 in dander and saliva both within and between breeds. Significantly higher levels were found in stallions compared to mares and geldings, independent of breed. Results suggest that none of the horse breeds studied can be recommended for individuals allergic to Equ c 4. This article is protected by copyright. All rights reserved.
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Purpose of Review The review provides insight into recent findings on bedroom allergen exposures, primarily focusing on pet, pest, and fungal exposures. Recent Findings Large-scale studies and improved exposure assessment technologies, including measurement of airborne allergens and of multiple allergens simultaneously, have extended our understanding of indoor allergen exposures and their impact on allergic disease. Practical, streamlined methods for exposure reduction have shown promise in some settings, and potential protective effects of early-life exposures have been further elucidated through the investigation of specific bacterial taxa. Advances in molecular allergology have yielded novel data on sensitization profiles and cross-reactivity. Summary The role of indoor allergen exposures in allergic disease is complex and remains incompletely understood. Advancing our knowledge of various co-exposures, including the environmental and host microbiome, that interact with allergens in early life will be crucial for the development of efficacious interventions to reduce the substantial economic and social burden of allergic diseases including asthma.
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This chapter discusses allergic rhinitis and conjunctivitis which are very common chronic illnesses in adolescence. Differential diagnosis and historical clues to make diagnosis in allergic rhinitis and conjunctivitis are reviewed. The importance and methods of making correct diagnosis and identification of relevant allergens are examined. The evidence to support recommended avoidance strategies and medical management are reviewed. Special consideration is given to adolescent patients in avoiding common pitfalls and finding a successful management strategy.
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Over the last 2 to 3 decades, significant advances have been made in understanding the role that indoor allergen exposures play with regard to respiratory health. Multiple studies have confirmed that sensitization and exposure to indoor allergens can be a risk factor for asthma morbidity. Environmental interventions targeting key indoor allergens have been evaluated with the aims of examining their causal effects on asthma-related outcomes and identifying clinically efficacious interventions to incorporate into treatment recommendations. Historically, it appeared that the most successful intervention, as performed in the Inner-City Asthma Study, was individually tailored, targeting multiple allergens in a predominantly low-income, minority, and urban pediatric population. Recent studies suggest that single-allergen interventions may be efficacious when targeting the most clinically relevant allergen for a population. In this article, we review recent literature on home environmental interventions and their effects on specific indoor allergen levels and asthma-related outcomes.
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Obeche wood is a prominent cause of allergic occupational asthma. To reduce the risk of immunoglobulin E (IgE)-mediated sensitization it is important to assess airborne obeche wood allergen concentrations at exposed workplaces. Therefore, a highly sensitive obeche wood allergen immunoassay was developed and applicability was proven on airborne passive dust samples in Spanish wood workshops. Obeche wood sandwich enzyme-linked immunosorbent assay (ELISA) polyclonal antibodies (pAbs) were developed. Test specificity was verified by different wood and mold extracts. Obeche wood allergen monitoring was conducted in four Spanish wood workshops, including wood-dust-exposed and nonexposed areas inside and outside the workplaces, as well as controls. Dust was collected with electrostatic dust collectors (EDC). Measuring range of the obeche wood sandwich-ELISA was between 36 pg/ml and 1.6 µg/ml. The test system showed only marginal reactivity to other hardwoods and no reactivity to softwoods and molds. Obeche allergen was detected in all EDC from workplaces. The highest concentration was measured in the workshop with the longest obeche wood exposure (geometric mean [GM]: 7548 µg/m²); shorter obeche wood processing periods resulted in lower amounts of allergen (GM: 29 µg/m²). Obeche wood allergen transfer from exposed workplaces to nonexposed areas inside and outside the workshop was assessed. In control EDC from nonexposed facilities/homes no obeche wood allergen was found. The new obeche wood sandwich-ELISA is a valid tool to quantify obeche allergen exposure. Evidence indicates it will be possible to monitor obeche allergen exposure during different processes, as well as transfer effects in nonexposed areas
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Despite the public interest in hypoallergenic dogs, few scientific, including epidemiological studies have attempted to evaluate claims of hypoallergenicity. This study was designed to determine whether dog breeds reported as hypoallergenic correspond to lower dog allergen in the home versus nonhypoallergenic dogs. A web search was conducted to identify breeds cited as hypoallergenic. Four separate classification schemes using combinations of purebred and mixed breed dogs were used to compare the levels of Canis familiaris 1 in dust samples collected from homes with hypoallergenic versus nonhypoallergenic dogs from an established birth cohort. No classification scheme showed that the level of dog allergen in homes with hypoallergenic dogs differed from other homes. Dog-allergic individuals should have access to scientifically valid information on the level of allergen shedding of different breeds of dogs.
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Exposure to allergens, both in general and occupational environments, is known to result in sensitisation and exacerbation of allergic diseases, while endotoxin exposure might protect against allergic diseases. This may be important for veterinarians and co-workers. However, exposure levels are mostly unknown. We investigated the allergen and endotoxin exposure levels of veterinary medicine students and workers in a companion animal hospital. Airborne and surface dust was collected using various sampling methods at different locations. Allergen levels in extracts were measured with sandwich ELISAs and/or the multiplex array for indoor allergens (MARIA). Endotoxin was determined by limulus amebocyte lysate (LAL) assay. Fel d 1 (Felis domesticus), Can f 1 (Canus familiaris) and endotoxin were detected in all except stationary samples. The geometric mean (GM) level of personal inhalable dust samples for Fel d 1 was 0.3 ng/m(3) (range: below lower limit of detection (<LOD) to 9.4), for Can f 1 3.6 ng/m(3) (<LOD to 73.3) and for endotoxin 4.4 EU/m(3) (<LOD to 75). Exposure levels differed significantly between job titles, with highest allergen exposure for student assistants in the intensive care unit (Fel d 1, GM 1.5 ng/m(3); Can f 1, GM 18.5 ng/m(3)), and highest endotoxin exposure for students (GM 10.1 EU/m(3)). Exposure levels in dust captured by diverse sampling methods correlated with each other (p<0.05). Allergen exposure likely occurs during veterinary practice, with relatively low endotoxin levels. Future research should investigate dose-response relationship between airborne allergen exposure and health effects.
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We recently introduced a passive dust sampling method for airborne endotoxin and glucan exposure assessment-the electrostatic dustfall collector (EDC). In this study, we assessed the effects of different storage and extraction procedures on measured endotoxin and glucan levels, using 12 parallel EDC samples from 10 low exposed indoor environments. Additionally, we compared 2- and 4-week sampling with the prospect of reaching higher dust yields. Endotoxin concentrations were highest after extraction with pyrogen-free water (pf water) + Tween. Phosphate-buffered saline (PBS)-Tween yielded significantly (44%) lower levels, and practically no endotoxin was detected after extraction in pf water without Tween. Glucan levels were highest after extraction in PBS-Tween at 120 degrees C, whereas extracts made in NaOH at room temperature or 120 degrees C were completely negative. Direct extraction from the EDC cloth or sequential extraction after a preceding endotoxin extraction yielded comparable glucan levels. Sample storage at different temperatures before extraction did not affect endotoxin and glucan concentrations. Doubling the sampling duration yielded similar endotoxin and only 50% higher glucan levels. In conclusion, of the tested variables, the extraction medium was the predominant factor affecting endotoxin and glucan yields.
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Dog dander is an important cause of respiratory allergy, but the spectrum of known dog allergens appears incomplete. Two lipocalins, Can f 1 and Can f 2, and serum albumin, Can f 3, have been characterized in detail but do not fully account for the IgE antibody-binding activity of dog dander extract. Allergen activity has previously been detected in dog urine but not further characterized. We sought to identify, characterize, and assess the importance of allergen components in dog urine. Dog urine was fractionated by means of size exclusion chromatography and examined for IgE antibody binding. A protein present in one fraction displaying IgE antibody-binding activity was identified by means of N-terminal sequencing and mass spectrometry. A recombinant form of the protein was produced in Pichia pastoris. IgE antibody binding to dog allergen components among sera of 37 subjects with dog allergy was determined by means of ImmunoCAP analysis. An IgE antibody-binding protein was isolated from dog urine and identified as prostatic kallikrein. A closely related or identical protein was detected in dog dander. The recombinant prostatic kallikrein displayed immunologic and biochemical properties similar to those of the natural protein and bound IgE antibodies from 26 (70%) of 37 sera of subjects with dog allergy, 14 of which reacted to none of Can f 1, Can f 2, or Can f 3. The dog allergen identified here was found to cross-react with human prostate-specific antigen, a key culprit in IgE-mediated vaginal reactions to semen. Prostatic kallikrein is a new major dog allergen.
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An extract of mixed dog hair and dandruff from six different dog breeds (alsatian, boxer, collie, poodle, and long-haired and short-haired dachshund) was obtained by mild extraction, centrifugation, dialysis and freeze-drying. Extract of hair and dandruff from the individual dog breeds was obtained in the same way, but the material was not freeze-dried. Examination and characterization of the mixed extract by means of crossed immunoelectrophoresis revealed a precipitation pattern composed of 25 antigens, some of which were mutually partially identical, and a high content of dog serum proteins was found. Quantitative and qualitative differences between the individual dog breeds were demonstrated. Partial identity of the antigens of the mixed extract with antigens of serum, antigens of extracts of hair and dandruff from cat, cow, horse and guinea pig, and antigens from extract of house dust was also observed. By means of crossed radioimmunoelectrophoresis, using sera from 21 patients who were RAST-positive to dog hair and dandruff extract, the specific IgE-binding to antigens of the mixed extract was examined. On the basis of these results major and minor allergens were identified. Dog albumin was found to be a very important major allergen, but alpha1-antitrypsin and gamma-globulin were also identified. Furthermore, four non-serum proteins were shown to be allergens. No breed-specific allergens could be identified in the extracts from the individual dog breeds.
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An important dog-hair and dander-specific allergen Ag13 has been purified by means of immunoaffinity chromatography utilizing rabbit antibody specific for Ag13. Purity was judged to be very high as detected by crossed immunoelectrophoresis and SDS-PAGE. The purified allergen was subjected to amino acid analyses. Molecular weight was about 22 kD in HPLC-gel filtration and 25 kD in SDS-PAGE with an additional band at 18 kD. In vitro IgE binding of the allergen was investigated by luminescence immunoassay (LIA) inhibition. Removal of Ag13 from dog hair and dander extract (DHD) removed 50 +/- 1.5% of the IgE binding capacity. The purified allergen inhibited up to 56.5% of the IgE activity to DHD as measured with a pool of serum from dog-allergic patients. Out of 26 dog-allergic patients, 24 had a positive skin-prick test to the allergen. Out of 23 dog-allergic patients, 16 reacted with the allergen in IgE immunoblotting. We suggest that Ag13 be termed Can f I. The allergen will be a marker allergen for environmental dog hair and dander exposure.
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This study aims to confirm that cat allergen 1 (CAT-1) is a major allergenic determinant in cat-sensitive patients, and to further define the role of other determinants, as well as to identify the determinants responsible for the cross-reactivity between cat and dog extracts. Firstly, the allergenic determinant with an electrophoretic mobility of 18 kD (corresponding to CAT-1) is indeed a major allergenic determinant being recognized by the majority (75%) of cat-sensitive subjects. Secondly, the cross-reactivity between the two species was confirmed by RAST inhibition. Cat and dog soluble allergens could inhibit, to variable degrees, the binding of serum IgE from cat- and dog-sensitive patients to insolubilized allergens. binding of serum IgE from subjects sensitive only to cats was inhibited by cat extracts only. These observations suggest the presence of determinants common to the two sources of extracts, and others specific for each species. These data were confirmed by immunoblot analysis. Indeed, an allergenic determinant of 69 kD was found in both cat and dog extracts. Conversely the allergenic determinants with an electrophoretic mobility of 18 and 32 kD were found only in cat extracts, and those at 22 and 24 kD were dog specific. However, surprisingly, serum IgE antibodies from patients sensitive only to cats reacted on immunoblot differently from those of both cat- and dog-allergic subjects. Indeed, the 18 kD determinant was the only one recognized by serum IgE antibodies from subjects sensitive to cats only, as opposed to the patients allergic to both species: then, the 69 kD determinant was strongly recognized and the 18 kD only slightly recognized.(ABSTRACT TRUNCATED AT 250 WORDS)
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Fifty-one patients with clinical history of dog allergy were skin prick tested with eight individual standardized dog breed-allergen preparations, one mixed breed-allergen preparation (Poodle/Alsatian), dog-serum albumin, and histamine hydrochloride, 1 mg/ml. All extracts were characterized by crossed immunoelectrophoresis and crossed radioimmunoelectrophoresis with a pool of sera from patients clinically sensitive to dog. The dog-breed extracts contained common antigens/allergens, as well as components represented only in one or two dog-breed extracts. The concentration corresponding 1000 BU/ml varied from 16 to 100 micrograms of protein per milliliter. The sensitivity of skin prick test was 67% to 88% for the various dog breed-allergen preparations, but only 18% for dog-serum albumin. Significant difference between the skin test response to different dog breed-allergen preparations indicating dog breed-specific allergens was obtained in 15% of the patients. There was no significant correlation between skin prick test results and symptoms related to a specific dog breed.
Article
The antigens present in an extract of dog hair and dander were examined by crossed immunoelectrophoresis (CIE) and the IgE-binding allergens by crossed radio-immunoelectrophoresis (CRIE), respectively, using sera from 60 British and Finnish animal-allergic subjects. The extract was comprised of a minimum of 28 antigens, 11 of which were common to dog serum. IgE antibody in the sera of the dog-sensitive patients bound to 21 of the 28 antigens at varying frequencies and intensities. Binding of any intensity occurred most frequently to two serum proteins: antigen 23 (IgG) binding IgE in 88% of cases, and antigen 3 (dog serum albumin, DSA) in 77% of cases. Dander antigen 8 bound in 63% and antigen 1 in 42% of the sera. Strong IgE binding, however, was most commonly associated with dander antigen 8 followed by antigens 1 and 23 (IgG) then 3 (DSA). The ranking of the antigens as allergens was similar for the two populations except that DSA was more important for the British than for the Finnish subjects.
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Our objective was to identify the allergens associated with asthma among schoolchildren in an area of the United States where dust mite growth is expected to be poor. Los Alamos, N.M., was chosen because it has low rainfall and is at high altitude (7200 feet) making it very dry. One hundred eleven children (12 to 14 years old) from the middle school who had been previously classified according to bronchial hyperreactivity to histamine (BHR) were studied. Sera were assayed for IgE antibodies to mite, cat, dog, cockroach, Russian thistle, and grass pollen, with both CAP system fluoroimmunoassay (Kabi Pharmacia, Uppsala, Sweden) and conventional RAST. Allergens were measured in dust samples from 108 homes with two-site assays for mite (Der p 1 and Der f 1), cat (Fel d 1), dog (Can f 1), and cockroach (Bla g 2). Concentrations of dog and cat allergens were elevated in almost all houses with pets but were also high in a significant proportion of the houses without pets. Levels of mite allergen were less than 2 micrograms/gm in 95% of the houses, and cockroach was undetectable in all but two of the houses. Among the 21 with BHR who had symptoms, 67% had IgE antibody to dog and 62% had IgE antibody to cat. For these allergens IgE antibody was strongly associated with asthma (p < 0.001). By contrast, the presence of IgE antibody to mite, cockroach, or grass pollen was not significantly associated with asthma. The high prevalence of IgE antibody to cat and dog allergens among these children is in keeping with the presence of cat and/or dog allergen in most of the houses. Furthermore, sensitization (as judged by IgE antibodies) to cat and dog allergens was strongly associated with asthma. On the other hand, no clear relationship was found between sensitization or symptoms and the current level of allergen in individual houses. The results show that in this mite-and cockroach-free environment sensitization to domestic animals was the most significant association with asthma.
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Exposure and sensitization to dog allergen is a significant cause of asthma. In this study we investigated the distribution, aerodynamic characteristics, and particle-size distribution of the major dog allergen Can f 1. Dust samples were collected in 50 homes with a dog and 50 homes without dogs. Airborne Can f 1 concentration was measured in 28 homes with dogs and 36 homes without a dog. Particle-size distribution was determined by using 10 separate Andersen sampler measurements in a dog-handling facility, and in 10 homes with dogs, and by repeated measurements in a home with one dog. High levels of Can f 1 (> 10 microg/g) were found in dust in all but one home with a dog and in eight of 50 homes without dogs. Airborne Can f 1 levels varied greatly between the homes with dogs (range: 0.3 to 99 ng/m3). Low levels of airborne Can f 1 (range: 0.4 to 1.1 ng/m3) were detected in 11 of 36 homes without a dog. Can f 1 was predominantly associated with large particles collected on the first stage of the Andersen sampler (> 9 microm), which averaged 42 to 49% of the total allergen recovered in the dog-handling facility and in homes with dogs. Small particles (< 5 microm diameter) also carried Can f 1, and these particles comprised approximately 20% of the total airborne allergen load. There was an excellent concordance between the results obtained in different sampling areas, and between the total Can f 1 recovered on the Andersen sampler and on the parallel filter. In conclusion, airborne Can f 1 was detectable in undisturbed conditions in all homes with dogs and in almost one third of the homes without dogs. In houses with dogs, a significant proportion (approximately 20%) of airborne Can f 1 was associated with small particles (< 5 microm diameter). Owing to their aerodynamic characteristics, these particles would be expected to remain airborne for a long period and, when inhaled, could penetrate into the lower airways and initiate asthma attacks.
Article
Simultaneous exposure to more than one allergen might modify the effect of individual allergens. The purpose of this study was to investigate the effect of current exposures to mite, cat, and dog allergen and pet ownership on sensitization in adults. Questionnaires, skin tests, and home visits (Der p 1, Fel d 1, and Can f 1, ELISA; mattresses, living room floors) were performed in 2502 adults. Allergen exposure was treated as a continuous variable and divided into quartiles. To investigate the interaction between allergens, quartiles for 3 allergens were added, creating arbitrary combined exposure categories. In the univariate analysis, mite sensitization was associated with Der p 1 in mattresses (odds ratio [OR], 1.10; 95% CI, 1.01 to 1.19; P =.03) and with Can f 1 in living room floors (OR, 1.08; 95% CI, 1.00 to 1.17; P =.05). In a multivariate regression analysis, Der p 1 in mattresses remained an independent associate of mite sensitization (OR, 1.12; 95% CI, 1.02 to 1.23; P =.03) and pollen sensitization (OR, 1.23; 95% CI, 1.11 to 1.36; P =.0001). The proportion of subjects sensitized to mite increased significantly with the increasing combined exposure categories (P <.0001). The highest prevalence of sensitization to cat and dog was in the medium combined exposure categories. Cat ownership was associated with a reduced prevalence of sensitization to cats (P =.002) and a reduced prevalence of sensitization to dog (P =.003) but had no effect on sensitization to mite and pollen. Sensitization to dust mites increased with the increasing combined exposure. Cat ownership was associated with a lower prevalence of sensitization to cat and dog but not to mite and grass pollen.
Article
Exposure to high levels of allergens in sensitized asthmatic patients causes worsening of pulmonary function in experimental studies. Chronic exposure to lower, naturally occurring levels of allergens might increase the severity of asthma. We sought to study the associations between sensitization and exposure to common indoor allergens (dust mite, cat, and dog) in the home on pulmonary function, exhaled nitric oxide (eNO), and airway reactivity in asthmatic patients. Dust samples were collected from the living room carpet and mattress of 311 subject's homes, and Der p 1, Fel d 1, and Can f 1 concentrations were measured by using ELISAs. Spirometry, nonspecific bronchial reactivity, and eNO were measured. Subjects both sensitized and exposed to high levels of sensitizing allergen had significantly lower FEV(1) percent predicted values (mean, 83.7% vs 89.3%; mean difference, 5.6%; 95% CI, 0.6%-10.6%; P =.03), higher eNO values (geometric mean [GM], 12.8 vs 8.7 ppb; GM ratio, 0.7; 95% CI, 0.5-0.8; P =.001), and more severe airways reactivity (PD(20) GM, 0.25 vs 0.73 mg; GM ratio, 2.9; 95% CI, 1.6-5.0; P <.001) compared with subjects not sensitized and exposed. No significant effect of the interaction between sensitization and exposure was found for FEV(1) percent predicted and eNO values. However, there was a significant effect of the interaction between sensitization and exposure to any allergen (P =.05) and between sensitization and exposure to cat allergen (P =.04) for nonspecific bronchial reactivity. Asthmatic subjects who are exposed in their homes to allergens to which they are sensitized have a more severe form of the disease.
Article
The clinical importance of dog allergy is well known, but it is unknown if all types of dogs represent the same risk for allergic patients. The purpose of this work was to evaluate among 288 healthy dogs if the levels of Can f 1 on fur vary between breeds (German Shepherd, Pyrenean Shepherd, Poodle, Cocker spaniel, Spaniel, Griffon, Labrador retriever and Yorkshire terrier), gender, hormonal status, hair length, and according to the presence of seborrhea. Each dog was shaved in a limited area and Can f 1 concentrations were measured in mug/g fur by ELISA. The results (geometric mean values and 95% confidence intervals) were analyzed using analysis of variance and with nonparametric tests. A wide variability in Can f 1 levels was found between dog breeds, from Labradors [1.99 (0.03-129.91)] to Yorkshires [16.72 (3.67-76.16)] and Poodles [17.04 (2.79-103.94)] but only the Labrador levels were significantly different from each other breed. Males produced more Can f 1 than females, 11.75 (1.27-108.40) vs 8.89 (0.91-86.39). No difference was found according to hair length or hormonal status. The seborrheic status highly (P = 0.0019) influenced the presence of Can f 1 on hair: 16.66 (1.59-173.96) vs 9.40 (1.03-85.70). Breeds (Labrador retriever), sex and seborrhea seem to influence the levels of Can f 1 on fur.
Article
Abstract Abstract Dust collection by study participants instead of fieldworkers would be a practical and cost-effective alternative in large-scale population studies estimating exposure to indoor allergens and microbial agents. We aimed to compare dust weights and biological agent levels in house dust samples taken by study participants with nylon socks, with those in samples taken by fieldworkers using the sampling nozzle of the Allergology Laboratory Copenhagen (ALK). In homes of 216 children, parents and fieldworkers collected house dust within the same year. Dust samples were analyzed for levels of allergens, endotoxin, (1→3)-β-D-glucans and fungal extracellular polysaccharides (EPS). Socks appeared to yield less dust from mattresses at relatively low dust amounts and more dust at high dust amounts than ALK samples. Correlations between the methods ranged from 0.47–0.64 for microbial agents and 0.64–0.87 for mite and pet allergens. Cat allergen levels were two-fold lower and endotoxin levels three-fold higher in socks than in ALK samples. Levels of allergens and microbial agents in sock samples taken by study participants are moderately to highly correlated to levels in ALK samples taken by fieldworkers. Absolute levels may differ, probably because of differences in the method rather than in the person who performed the sampling.
Article
Recombinant dog allergens, rCan f 1 and rCan f 2, and their antibodies are good tools for the characterization of dog allergens in order to develop modern therapeutic and preventive methods for dog allergy. In this study, cDNA was synthesized from the mRNA of dog salivary glands and cloned into the pGEX4T vector. rCan f 1 and rCan f 2 containing glutathione S-transferase were prepared by an Escherichia coli expression system. The antibodies against the recombinant allergens were prepared in rabbit. The serum of patients with dog allergy was evaluated by ELISA and immunoblot, using the recombinant allergens, goat anti-human immunoglobulin (Ig) E (epsilon) labeled with biotin, and enzyme-labeled streptavidin. The binding of IgE in the serum of patients with dog allergy to dog saliva as a natural antigen was determined in the presence or absence of dog saliva, rCan f 1 and rCan f 2 as competitors. The anaphylactic potential of rCan f 1 and rCan f 2 was evaluated. The body temperature of the mice sensitized with rCan f 1 and rCan f 2 was monitored after intravenous injection of the allergens. The passive cutaneous anaphylaxis reaction was examined for rCan f 1 and rCan f 2. Dog salivary glands, dog saliva and dog hair/dander extracts were analyzed with antibodies by means of an immunoblot assay. The expression of the mRNA of Can f 1 and Can f 2 was verified in various dog tissues by reverse transcription polymerase chain reaction. The E. coli expression system revealed the yield of rCan f 1 and rCan f 2 in 36 and 30 mg/l of culture. The molecular weights of rCan f 1 and rCan f 2 were 18 and 20 kDa in SDS-PAGE, respectively. rCan f 1 and rCan f 2 were found to bind to specific IgE in the serum of dog allergy patients. The binding of IgE in the patient serum for dog saliva was partially inhibited in the presence of rCan f 1 and rCan f 2. These recombinant allergens showed positive signals in passive cutaneous anaphylaxis reaction and induced anaphylactic shock in the mouse model, resulting in a decrease in body temperature. The polyclonal rabbit antibody for rCan f 1 bound to a protein of 20 kDa in the salivary gland, saliva and hair/dander extracts of dogs. The rabbit antibody for rCan f 2 bound to proteins in the saliva and the hair/dander extracts. The proteins possessed a molecular weight of 22/ 23 kDa. Reverse transcription polymerase chain reaction showed the presence of mRNA expression of Can f 1 and Can f 2 not only in the salivary gland but also in dog skin. A clear expression of Can f 2 mRNA was observed in dog skin. The recombinant allergens and antibodies for Can f 1 and Can f 2 are available for immunological and biochemical characterization of dog allergens. The molecular weight of the natural Can f 1 and Can f 2 in dog saliva and hair/dander extracts showed a higher molecular weight than that of rCan f 1 and rCan f 2. The significance of dog skin as the tissue producing dog allergens, especially Can f 2, should be considered in further studies.
Article
In our environment, dogs are a relevant source of allergens, but diagnosing dog-related allergies may present difficulties, as in diagnostic tests with commercial dog allergens, some patients show only slight positive or negative results, even though they suffer from dog-related symptoms. Occasionally, allergy tests with extracts of dog hair belonging to patients' dogs or from dogs of the same breed were found to yield more reliable results, possibly due to breed-specific allergen components. The purpose of this study was to determine breed-specific differences or possibly hypo- or hyperallergenic dog breeds. The dog allergen content and protein patterns of different commercial and self-prepared dog allergen extracts were compared. Protein extracts were separated using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and stained with silver. The major allergen Can f 1 was quantified using the commercially available enzyme-linked immunosorbent assay (ELISA) technique. The majority of the bands in the self-prepared extracts of different breeds had a molecular mass lower than 30 kD. Notably, the self-prepared extracts of hair of common breeds showed distinct protein bands with a molecular mass lower than 14 kD, which the commercial extracts did not. With regard to Can f 1 content, a marked variability occurred. Factors related to individual dogs seem to influence the allergenicity more than breed or gender. This is the first report to describe allergens with low molecular mass that are absent in extracts of commercial test kits. Consequently, skin tests with self-prepared dog allergen extracts need to be performed in case of inconsistent test results with commercial extracts.
Qualitative differences among canine danders
  • Sb Hooker
Hooker SB. Qualitative differences among canine danders. Ann Allergy 1944;2: 281