Dog Allergens Research Articles

Equivalence in intradermal reactions to histamine and compound 48/80 in dogs before and after sedation with dexmedetomidine or a 1:20 combination of medetomidine and vatinoxan.

Intradermal allergen testing (IDAT) is commonly used to formulate allergen-specific immunotherapy, a pillar treatment for canine atopic dermatitis. Many sedatives have shown histaminergic or anti-histaminergic effects and thus been deemed unsuitable for IDAT. The goal of this study was to determine whether, in healthy dogs, dexmedetomidine (Dexdomitor) or a 1:20 combination of medetomidine and vatinoxan (Zenalpha) will affect intradermal reactions compared to unsedated dogs. Ten privately owned healthy dogs were enrolled in this equivalence study. Wheal formation was subjectively and objectively assessed in conscious then sedated dogs. Dogs were randomly sedated with either Dexdomitor (dexmedetomidine [0.5 mg/m2]) or Zenalpha (medetomidine [1 mg/m2/vatinoxan] 20 mg/m2) intramuscularly. Once sedated, five 10-fold histamine (100-0.01 μg/mL) and compound 48/80 (200-0.02 μg/mL) dilutions were intradermally injected into the lateral thorax. The study was repeated on the opposite side with the alternative sedation 1 week later. Quality of sedation, cardiorespiratory function and rectal temperature were recorded every 5 min. There was no difference in the median values of the reactions with either sedative when compared to unsedated dogs. Dexdomitor and Zenalpha achieved an equivalence in both subjective and objective scoring systems for all concentrations tested. A faster median time to sedation (10 vs. 18 min, p = 0.013) was seen with Zenalpha compared to Dexdomitor. Although both sedatives depressed the cardiovascular function, such parameters were less affected by Zenalpha than by Dexdomitor (p ≤ 0.001). Owing to the lack of effects on wheal formation, both sedatives are appropriate for sedating dogs undergoing IDAT. Although, such results should be validated in allergic dogs. Zenalpha may induce more rapid and reliable sedation than Dexdomitor.

Validation of a Multiplex Molecular Macroarray for the Determination of Allergen-Specific IgE Sensitizations in Dogs.

Detecting IgE sensitizations in the serum of allergic dogs is commonly performed using allergen extracts, but these are difficult to standardize. This article details the development and validation of the Pet Allergy Xplorer (PAX; Nextmune, Stockholm, Sweden), the first multiplex macroarray for the detection of IgE sensitization in dogs using allergen extracts and molecular components; the PAX is derived from the Allergy Xplorer (ALEX2; MacroArray Diagnostics, Vienna, Austria). The selection of allergens, cartridge processing, strategy for identifying and blocking IgE directed against cross-reactive carbohydrate determinants (CCDs), and the method used for determining the positivity threshold are described. The validation of the PAX included evaluations of the specificity of its anti-IgE monoclonal antibody, specificity of IgE binding to target allergens, assay precision, and internal consistency. Additionally, the influence of possible confounding factors, such as sample type, the influence of hemolysis, lipemia, bilirubinemia, and elevated CCD-IgE, was tested. Finally, the sensitization rates of 23,858 European dogs to 145 environmental and Hymenoptera venom allergens were summarized. The PAX is accurate and reproducible and has a unique CCD-detection and blocking strategy; its molecular allergens offer a unique window on allergen cross-reactivity.

Allergies to Allergens from Cats and Dogs: A Review and Update on Sources, Pathogenesis, and Strategies

Inhalation allergies caused by cats and dogs can lead to a range of discomforting symptoms, such as rhinitis and asthma, in humans. With the increasing popularity of and care provided to these companion animals, the allergens they produce pose a growing threat to susceptible patients’ health. Allergens from cats and dogs have emerged as significant risk factors for triggering asthma and allergic rhinitis worldwide; however, there remains a lack of systematic measures aimed at assisting individuals in recognizing and preventing allergies caused by these animals. This review provides comprehensive insights into the classification of cat and dog allergens, along with their pathogenic mechanisms. This study also discusses implementation strategies for prevention and control measures, including physical methods, gene-editing technology, and immunological approaches, as well as potential strategies for enhancing allergen immunotherapy combined with immunoinformatics. Finally, it presents future prospects for the prevention and treatment of human allergies caused by cats and dogs. This review will improve knowledge regarding allergies to cats and dogs while providing insights into potential targets for the development of next-generation treatments.

Quantitative filter forensics for allergens and semivolatile organic compounds in residential buildings in Toronto, Canada

Quantitative filter forensics (QFF) is a method for estimating the time-averaged concentration of particle-bound containments using filter metadata and its extracted dust. In this study, QFF was applied to dust samples extracted from four types of HVAC filters deployed in 20 homes from December 2016 to December 2017 in Toronto, Canada. The analysis covered six allergens, eight phthalates, and 12 polycyclic aromatic hydrocarbons (PAHs). The allergen results from four homes showed elevated concentrations of cat and dog allergens (Fel d 1 and Can f 1) in homes with cats or dogs. All eight phthalates were detected, dominated by diisononyl phthalate (DiNP) and bis(2-ethylhexyl) phthalate (DEHP), with median concentrations of 4.27 ng/m³ and 4.20 ng/m³, respectively. All PAHs, except anthracene, were detected in over 50 % of the homes, with benzo[a]pyrene being the most abundant (median concentration of 0.067 ng/m³). Median concentrations of all semivolatile organic compounds (SVOCs) were lower in winter 2016 compared to spring 2017, potentially due to losses of more volatile SVOCs from filters because of higher filtration volumes in winter, in addition to differences in sources and ventilation rates. All phthalate and most PAH concentrations were one to two orders of magnitude lower compared to those found from QFF in apartments in Toronto social housing multi-unit residential buildings (MURB), indicating those with lower socio-economic status (SES) were exposed to higher SVOC concentrations. Occupant density was positively related to most phthalate and specific PAH concentrations, while environmental factors including room temperature, relative humidity, and supply air temperature were not.

Dog Allergy in Children: A Single-Centered Study

Introduction: Dogs are among the most commonly allergenic pets for children. Data on risk factors for the development of dog allergy are scarce. This study aimed to evaluate the characteristics of children with dog allergy and identify predictors of symptom development with dog exposure. Methods: The study included children with dog allergen sensitization demonstrated by skin prick test (SPT) between September 1, 2019, and December 1, 2022. Demographic, clinical, and laboratory data were collected from the patients’ records and interviews with parents. Results: Dog allergen sensitization was detected by SPT in 548 (5.5%) of 9,907 patients. Of these, 507 patients had complete data and were included in the analysis. The patients’ median age was 11 (IQR: 8–15) years, 55.8% were male, 97.6% exhibited polysensitization (pollen 75.1%, cat 69.6%), 83.6% had allergic rhinitis, and 46.2% had asthma. Acute dog exposure caused symptoms in 164 patients (32.3%), most commonly sneezing (n = 97) and nasal symptoms (n = 80). Predictors of acute symptoms in dog-sensitized children were male sex (OR: 0.584 [CI: 0.38–0.87]), dog exposure before 1 year of age (OR: 2.35 [CI: 1.18–4.66]), close contact with a dog owner (OR: 2.93 [CI: 1.78–4.8]), and cat allergy (OR: 2.75 [CI: 1.82–4.1]). Conclusion: Approximately one-third of children with dog sensitization developed symptoms after exposure to the dog. Male sex, direct dog exposure before the age of one, close contact with a dog owner, and cat allergy were identified as predictors of dog allergy.

Advancing diagnostic precision: Unveiling sensitization relationships between cat, dog, and horse allergen molecules.

Recent advancements in molecular diagnostics have unveiled a multitude of allergen molecules (AMs) associated with animal sensitizations, revealing significant cross- and co-sensitization patterns among these seemingly distinct allergens. We investigated the sensitization profiles of 120 children, sensitized to at least one of the 14 AMs from cat, dog, or horse using the Alex test, employing correlations and hierarchical clusters to explore relationship between sensitizations. Sensitizations to Fel d 1, Can f 4/5, and Equ c 4 differ from other cat, dog, and horse AM sensitizations, suggesting they may represent genuine sensitizations for their respective animals. High correlations were observed among various AMs, including lipocalins (Can f 1/2/6, Fel d 4/7, and Equ c 1), serum albumins (Fel d 2, Can f 3, and Equ c 3), and uteroglobins (Fel d 1 and Can f_Fd1). Hierarchical clustering of sensitizations identified two similarity clusters and one dissimilarity cluster, providing an estimation of the likelihood of cross-reactivity. Additionally, our method facilitated speculation regarding cross-, co-, or genuine sensitization. Moreover, we noted a potential increase in the number and level of sensitized animal AMs concurrent with increased sensitization to other aeroallergens with advancing age. No significant difference was detected for the presence or absence of various types of allergic comorbidities. Correlations and hierarchical clustering can unveil the extent and magnitude of cross-, co-, and genuine sensitization relationships among animal AMs. These insights can be leveraged to enhance artificial intelligence algorithms, improving diagnostic accuracy through the integration of other measures of sensitization.

Systemic IL-26 correlates with improved asthma control in children sensitized to dog allergen

BackgroundInterleukin (IL)-26 is produced by T helper type 17 (Type 17) cells and exerts immunomodulatory plus antimicrobial effects. Previous studies show that local IL-26 concentrations in the airways are higher in patients with uncontrolled than in those with controlled asthma, and that this intriguing cytokine bears biomarker potential. Here, we determined how systemic IL-26 relates to allergen sensitization, asthma severity, and to IL-17 A in children.MethodsSerum samples were obtained from children with (n = 60) and without (n = 17) sensitization to dog allergen, and IL-26 and IL-17 A protein concentrations were measured using ELISA. Self-reported history, including medication use and validated symptom-based questionnaire scores, was recorded.ResultsThe serum concentrations of IL-26 were enhanced in allergen-sensitized subjects and correlated with those of IL-17 A in a positive manner. However, the IL-26 concentrations did not markedly differ between allergen-sensitized subjects with and without asthma, eczema, allergic rhinitis, or a history of food allergy. Notably, IL-26 concentrations correlated with increasing Asthma Control Test (ACT) scores in a positive manner and with inhaled corticosteroid in a negative manner, amongst sensitized subjects with asthma. Moreover, subjects with asthma requiring ≥ 1 course of oral corticosteroids in the preceding 12 months had decreased IL-26 concentrations.ConclusionThis study forwards evidence that systemic IL-26, just like IL-17 A, is involved in allergen sensitization among children. The association of systemic IL-26 with improved asthma control is compatible with the cellular sources being recruited into the airways in severe asthma, which supports that this kinocidin bears potential as a biomarker and therapeutic target.

ПРОФИЛИ МОЛЕКУЛЯРНОЙ СЕНСИБИЛИЗАЦИИ К АЛЛЕРГЕНАМ ПУШНЫХ ЖИВОТНЫХ У ПАЦИЕНТОВ РОССИЙСКОЙ ФЕДЕРАЦИИ

Molecular sensibilization patterns have not been yet described for the Russian population, which makes it difficult to develop prevention, elimination and treatment methods for patients with allergic pathology. The purpose of this research was to analyze patterns of sensibilization to components of fur animal allergens in patients examined in order to exclude the sensibilization. Materials and methods used: results of 1113 Immuno Solid-phase Allergen Chip (ISAC) in patients with suspected atopy were analyzed. In all patients, sIgE concentrations to allergenic components of fur animals were determined. Results: 468 (58.21%) of 1113 were found to have sensibilization to fur animal allergens. Of these, 396 (84.62%) were sensibilized to the cat, 277 (59.19%) to the dog, 98 (20.94%) to the horse, and 26 (5.55%) to the mouse. sIgE to Fel d 1 was determined in 90.91% of patients with cat sensibilization, and the median concentration of sIgE to Fel d 1 was higher than to Fel d 2 (p=0.011) and Fel d 4 (p<0.001) (5.4 [1,7; 15]). ISU-E, sIgE to Can f 1 was detected in 73.29%, to Can f 2 - in 18.05%, to Can f 5 - in 41.52% of patients sensibilized to dogs. Among children under 9 y/o, the frequency of detection of sensitization to Can f 5 was less frequent than in the group of children aged over 10 y/o and adults (p<0.001). Conclusion: the Russian population is characterized by a high prevalence of sensibilization to fur animal allergens. Most patients had polysensibilization to components of cat (Fel d 1) and dog (Can f 1, 2 and 5) allergens. It was revealed that Can f 2 has a higher allergenic potential, which in its turn allows it to be identified as a major dog allergen. 92.55% of patients with sensibilization to Fur-bearing animals have an increased risk of developing asthma.

Development and validation of a questionnaire to assess owner and canine quality-of-life and treatment satisfaction in canine allergic dermatitis.

Animal and owner quality-of-life (QoL) is pivotal in treatment decisions. Accurate measurement of owner-reported QoL and treatment satisfaction (TS) supports disease burden and treatment benefit evaluation. Develop and evaluate an owner-completed canine dermatitis QoL and TS questionnaire (CDQoL-TSQ) in allergic dogs. The CDQoL-TSQ was drafted following review of existing measures and expert input. Content validity was assessed through interviews with owners of allergic dogs. Psychometric properties of the QoL domains (Canine QoL, Owner QoL) were evaluated. Score interpretation was derived. Twenty dog owners were interviewed. Item wording was amended following the first 10 interviews. Data from 211 owners were used in the psychometric evaluation. The Canine QoL domain demonstrated strong internal consistency (α = 0.89), test-retest reliability (ICC2,1 = 0.844), moderate convergent validity (r = 0.41) and moderate-high known-groups validity (effect size 0.37-0.64). The Owner QoL domain demonstrated strong internal consistency (α = 0.73), high convergent validity (r = 0.63) and moderate-high known-groups validity (0.43-0.63). Test-retest reliability approached moderate strength (ICC2,1 = 0.490). Group-level interpretation analysis showed minimal important difference of 7.0-13.6 points for dogs and 13.0-13.6 for owners. For individual dogs a change of 6.3 or 12.5 points for dogs, and 12.5 or 18.8 for owners indicates a response. The CDQOL-TSQ is a two-part assessment to evaluate QoL and TS in canine allergic dermatitis. The QoL questionnaire demonstrated validity and reliability, and interpretation of scores was derived, making it suitable for use in research and practice. The TS module is suitable for clinical setting use to improve owner-veterinarian communication.

Relationship between indoor inhalant allergen concentrations, serum IgE, and allergic diseases: A cross-sectional study from the NHANES 2005–2006 program

This research analyzed data from 5106 participants in the National Health and Nutrition Examination Survey 2005–2006 to explore the link between indoor allergen concentrations, serum IgE levels, and allergic diseases. The study found that 14.9% of participants reported having asthma, with significant differences noted in the concentrations of certain indoor allergens, specifically dust dog, mite, and cat allergens, between asthma and non-asthma groups. Furthermore, positivity rates for inhalant allergen-specific IgE and total IgE were higher in the asthma group. However, the correlations between most inhalant allergen IgE, including total IgE, and indoor allergen concentrations were very weak. These findings suggest that the relationship between indoor allergen concentrations and asthma incidence is complex, indicating a potential need for personalized allergen prevention strategies based on disease type and patient sensitization.

The Impact of the Pandemic on Cat and Dog Allergies.

The impact of the COVID-19 pandemic on allergic patients is not clearly understood. The aim of this study is to investigate the changes in sensitivity to cat and dog allergens in patients with respiratory allergies in Istanbul during the COVID-19 pandemic. Before the pandemic (March 2018 - March 2020) and during and after the pandemic (March 2020 - March 2022), a total of 5499 patients who underwent skin testing were retrospectively evaluated. The patients' age, gender, diagnosis, total IgE, and eosinophil values were recorded. Patients were divided into two groups: 2-6 years old and 7 years and older. The frequency of sensitization to cats and dogs was investigated in both groups before and after the pandemic. The median age of the 5499 children included in the study was 77 months, with a range of 2 to 221 months. Furthermore, 55.7% of the children were male. Of the children, 59.1% were examined before the pandemic, and 40.9% during and after the pandemic. During the examinations, allergic rhinitis was identified in 1628 children (29.6%), asthma in 1829 children (33.3%), and both asthma and allergic rhinitis in 2042 children (37.1%). Allergies to cats were found in 247 children (4.5%), and to dogs in 166 children (3.0%). When comparing the age groups, the frequency of cat allergy in the 7-years and older group was found to have decreased compared to the pre-pandemic period, and the statistical difference was close to significance (p=0.08). However, regarding dog allergy, in the 7 years and older group, the sensitivity to dogs, which was 5.6% before the pandemic, had decreased to 2.6% during the pandemic, and this decrease was found to be statistically highly significant (p<0.001). Environmental allergen exposure has a significant impact on the phenotype of allergic diseases. Changes in patients' lifestyles and increased time spent at home during the pandemic may have led to a decrease in contact with outdoor cat and dog allergens, resulting in a reduced frequency of cat and dog sensitivity. Additionally, the introduction of mask-distance-handwashing/disinfection rules during the pandemic is believed to have reduced contact with cat and dog allergens, potentially contributing to a decrease in allergy frequency.

Purification of living environments using photocatalysts: inactivation of microorganisms and decomposition of allergens.

Many emerging and re-emerging infectious diseases are prevalent, and the number of patients with allergies is increasing. Therefore, the importance of purifying the living environment is increasing. Photocatalysts undergo extreme redox reactions and decompose organic matter upon exposure to the excitation light. In contrast to ultraviolet light and disinfectants, which are standard methods for inactivating viruses and eliminating microorganisms, photocatalysts can decompose toxic substances, such as endotoxins and allergens, rendering them harmless to the human body. Photocatalysts have attracted significant attention as potential antiviral and antimicrobial agents. This review outlines the antiviral, antimicrobial, and anti-allergenic effects of photocatalysts. Especially, we have discussed the inactivation of SARS-CoV-2 in liquids and aerosols, elimination of Legionella pneumophila in liquids, decomposition of its endotoxin, decomposition of cat and dog allergens, and elimination of their allergenicity using photocatalysts. Furthermore, we discuss future perspectives on how photocatalysts can purify living environments, and how photocatalytic technology can be applied to companion animals and the livestock industry.

The functional role of CST1 and CCL26 in asthma development.

Asthma is the most common chronic disease in children with an increasing prevalence. Its development is caused by genetic and environmental factors and allergic sensitization is a known trigger. Dog allergens affect up to 30% of all children and dog dander-sensitized children show increased expression of cystatin-1 (CST1) and eotaxin-3 (CCL26) in nasal epithelium. The aim of our study was to investigate the functional mechanism of CST1 and CCL26 in the alveolar basal epithelial cell line A549. A549 cells were transfected with individual overexpression vectors for CST1 and CCL26 and RNA sequencing was performed to examine the transcriptomics. edgeR was used to identify differentially expressed genes (= DEG, |log2 FC | ≥ 2, FDR < 0.01). The protein expression levels of A549 cells overexpressing CST1 and CCL26 were analyzed using the Target 96 inflammation panel from OLINK (antibody-mediated proximity extension-based assay; OLINK Proteomics). Differentially expressed proteins were considered with a |log2 FC| ≥ 1, p < .05. The overexpression of CST1 resulted in a total of 27 DEG (1 upregulated and 26 downregulated) and the overexpression of CCL26 in a total of 137 DEG (0 upregulated and 137 downregulated). The gene ontology enrichment analysis showed a significant downregulation of type I and III interferon signaling pathway genes as well as interferon-stimulated genes. At the protein level, overexpression of CST1 induced a significantly increased expression of CCL3, whereas CCL26 overexpression led to increased expression of HGF, and a decrease of CXCL11, CCL20, CCL3 and CXCL10. Our results indicate that an overexpression of CST1 and CCL26 cause a downregulation of interferon related genes and inflammatory proteins. It might cause a higher disease susceptibility, mainly for allergic asthma, as CCL26 is an agonist for CCR-3-carrying cells, such as eosinophils and Th2 lymphocytes, mostly active in allergic asthma.

Residual profiles and health risk of indoor allergens in China

Exposure to indoor allergens is a principal risk factor for allergic diseases. However, most of the previous studies on indoor allergens focused on very limited kinds of allergens in China. Knowledge of the simultaneous exposure to multiple allergens is still lacking. In this study, the residual profiles of 8 allergens were investigated in 166 dust samples from 11 cities in China. The house dust mite allergens including Der p 1, Der f 1, and Der 2 were detected in the range of <0.02–283.83 μg/g dust. The concentrations of dog allergen Can f 1 and cat allergen Fel d 1 varied widely, from <0.84–22,896.46 μg/g dust for Can f 1 and from <0.02–6298.96 μg/g dust for Fel d 1. Cockroach allergen Bla g 2 was detected in 68% of the samples but at a low level with a maximum of 9.44 μg/g dust. Comparatively low detection frequencies were found for mouse allergen Mus m 1 as 37% and for fungi allergen Asp f 2 as 24%. The frequency of cleaning sheets/bedding was negatively correlated to the levels of house dust mite allergens. The presence of pets indoors was associated with higher levels of pet allergens and lower levels of house dust mite allergens and cockroach allergen. Risk evaluation reveals that at least 4 allergens were found in more than 80% of the rooms and more than 2 allergens with median/high risk were detected in 42% of the rooms, indicating that simultaneous exposure to multiple allergens is prevalent in China.

Survey of Sensitization to Common Fungi in an Allergic Dog Population: The Need for Further Focus on Sensitization and Allergy to Fungi in Veterinary Medicine.

Most fungal species are commensals and non-pathogenic to plants, humans, or animals. However, several species of the Alternaria, Aspergillus, Trichophyton, and Microsporum genera are common causes of disease, even for immunocompetent individuals. Besides mucosal damage, fungi may contribute to a skin barrier impairment, favoring sensitization and allergy development. A total of 68 allergic dogs were selected from a veterinary dermatology and allergy outpatient consultation for conditions related to both Malassezia overgrowth and other fungal complications. The allergy diagnosis was made through anamnesis and current clinical criteria, with the involved allergenic species being identified by intradermal tests (IDTs) and allergen-specific immunoglobulin E (sIgE) determination in serum. Dermatophagoides farinae, Dactylis glomerata, and Malassezia pachydermatis showed as the higher sensitization species from house dust mites, grass pollen, and fungi, respectively. Significant correlations at p < 0.05 were found between sensitization to Dactylis glomerata and Phleum pratense grass pollens, Dermatophagoides farinae and Dermatophagoides pteronyssinus, Acarus siro, Tyrophagus putrescentiae, and Lepidoglyphus destructor dust/storage mites, and between fungi like Aspergillus mix and Penicillium or Alternaria alternata. A significant correlation was also found between sensitization to the Aspergillus mix and D. farinae, D. pteronyssinus, or A. siro. Rather severe dermatitis was observed when a positive IDT to Malassezia pachydermatis was found, regardless of the detection of circulating sIgE, allowing us to consider the usefulness of both the IDT and the sIgE for a systematic diagnosis of allergy to fungi.

Increasing Prevalence of Sensitization to Cat/Dog Allergens in the COVID-19 Pandemic

Introduction: Cat and dog allergens are common indoor triggers for respiratory allergies such as allergic rhinitis and asthma. This study aims to evaluate the prevalence of cat and dog allergies in adults and analyze changes during the COVID-19 pandemic. Methods: We retrospectively analyzed the medical records of 8,102 patients who visited an allergy clinic and underwent skin prick testing (SPT) from March 2018 to March 2022: 2 years before and 2 years during the pandemic. Demographic information, clinical attributes, and laboratory results were examined based on patient records. Results: Of 8,102 SPTs performed, 400 (4.9%) were sensitized to cat allergen and 289 (3.6%) to dog allergen. Allergic rhinitis was the predominant clinical diagnosis in both groups. Of the 400 subjects exposed to cats, 240 (60%) experienced allergic symptoms, while of the 289 subjects exposed to dogs, 65 (22.5%) experienced allergic symptoms during exposure. Within the cat-sensitized group, anaphylaxis was observed in 5 patients (1.3%), while no cases of anaphylaxis were reported in the dog-sensitized group. Compared to the pre-pandemic period, patients presenting during the pandemic had higher rates of cat and dog sensitization (5.7% vs. 4.1%; p < 0.05, 5.2% vs. 1.7%; p < 0.05). Conclusion: During the COVID-19 pandemic, there was an increase in cat and dog allergies among adults. Increased exposure to pet antigens, both directly and indirectly, has resulted in more people becoming sensitized to cats or dogs.

Molecular sensitization patterns to cat and dog allergens in Lithuanian children population

BackgroundOver the last few decades, there was observed an increase of asthma and allergic rhinitis cases caused by allergy to pets. ObjectiveThis study aimed to analyze molecular sensitization patterns to dog and cat allergens in Lithuanian children who were experiencing allergy-like symptoms. Materials and methodsA total of 574 children (0–18 years) were tested for allergen-specific immunoglobulin E (sIgE) levels with ALEX2 (ALEX2®, Allergy Explorer Test System). Positive sera were further analyzed for sensitization to cat (Fel d 1, Fel d 2, Fel d 4, and Fel d 7) and dog (Can f 1, Can f 2, Can f 3, Can f 4, Can f 5, and Can f 6) allergen components. ResultsTwo hundred forty-seven children tested positive (sIgE ≥0.3 kUA/L) to at least 1 dog or cat allergen component. There were 61.1% children sensitized to components from both sources, 29.2% – exclusively to cat, and 9.7% – to dog components. The major sensitizers were Fel d 1 (84.8%) and Can f 1 (59.4%). There were 42.9% patients sensitized to 3 or more different mammalian protein families and 40.4% – to 3 or more lipocalins. There were 5.7% of children sensitized both to Fel d 1 + Fel d 4 and Can f 1/2 + Can f 5, indicating the high risk of severe asthma. Monosensitization to Fel d 1 was the dominant pattern among Lithuanian children (26.3%). ConclusionThe majority of children were cat/dog-polysensitized, although sensitization only to cat allergens was most observed. Extensive molecular profiling can be an useful tool for accurate true sensitization diagnosis and prognosis of disease severity.

A randomised, double-blinded trial to assess the effect of oclacitinib and prednisolone on intradermal allergen and prick tests in dogs with atopic dermatitis.

Intradermal (IDT) and prick (PT) tests are used to select allergens for allergen-specific immunotherapy in dogs with atopic dermatitis (cAD). However, the use of antipruritic drugs before performing these tests may influence the results. To evaluate the influence of the drugs oclacitinib and prednisolone on the immediate-phase reactions of IDT and PT. Thirty client-owned dogs with cAD with positive reactions to at least one allergen extract on IDT or PT. Dogs were randomly assigned to receive oclacitinib 0.4-0.58 mg/kg per os, every 12 h (n = 14), or prednisolone 0.37-0.65 mg/kg p.o., every 12 h (n = 16) for 14 days. IDT and PT were performed on Day (D)0 before treatment and on D14. At D14 there was no significant reduction in the means of the orthogonal diameters of the positive immediate-phase reactions of the IDT (p = 0.064) in the oclacitinib group; however, in the PT, the diameter of the positive reactions reduced significantly (p = 0.048). In both tests, there was no significant reduction in the total number of positive reactions (IDT, p > 0.999; PT, p = 0.735). In the prednisolone group, the means of the orthogonal diameters of positive immediate-phase reactions were significantly reduced in both tests (IDT, p = 0.001; PT, p ≤ 0.001) and there also was a reduction in the total number of positive reactions (IDT, p = 0.022; PT, p = 0.001). The use of oclacitinib 0.4-0.58 mg/kg twice daily for 14 days does not interfere with IDT results in dogs with cAD. However, oclacitinib may reduce PT reactivity. The use of prednisolone 0.37-0.65 mg/kg twice daily results in a reduction in both IDT and PT results.

Seroprevalence of Dermatophagoides farinae-specific IgE in dogs with atopic dermatitis in São Paulo, Brazil

Canine atopic dermatitis (CAD) is a chronic, inflammatory, and pruritic disease of the skin resulting from the loss of the epidermal barrier, sensitization, and exacerbated production of IgE antibodies mainly directed against environmental allergens, especially to house dust mites. To select specific allergen immunotherapies with high efficacy, there are necessary studies with house dust mite allergens to improve both serological and intradermal tests. Therefore, the objective of this study was to evaluate the seroprevalence of IgE against Der f 2, Zen 1, and crude Dermatophagoides farinae allergens in dogs with AD in the State of São Paulo, Brazil. The sera of 85 dogs with clinically confirmed atopic dermatitis from the State of São Paulo (Brazil) was collected. In addition, an indirect ELISA test was conducted to detect allergen-specific serum IgE. IgE seropositivity was observed in 97.5% of the dogs for Der f 2, 95.0% for Zen 1, and 92.5% for the crude mite allergens. Due to this high prevalence of IgE specific to these allergens, we suggest that Der f 2 and Zen 1 can be considered major allergens for dogs in the State of São Paulo.

Cross-reactive carbohydrate determinants in atopic and healthy dogs and their influence on allergy test specificity.

The selection of allergens for immunotherapy in atopic dogs is often based on serum allergy testing. Cross-reactive carbohydrate determinants (CCDs) are common structures in plant and insect allergens that reportedly induce polysensitisation, reduce agreement between intradermal and serum tests and complicate allergen selection. Thirty-four dogs with diagnosed atopic dermatitis and 10 healthy dogs were included in the study. An intradermal test was conducted in atopic dogs, and serum samples from allergic and healthy dogs were analysed for allergen-specific immunoglobulin E (IgE) before and after inhibition of detectable anti-CCD-IgE antibodies. Anti-CCD-IgE antibodies were not found in any of the healthy dogs and no polysensitisation to plant and insect allergens was detected. The agreement between intradermal and serum allergy test results in the atopic dogs with anti-CCD-IgE antibodies improved from slight to fair after blocking the anti-CCD-IgE antibodies. In addition, blocking clearly reduced polysensitisation to plant allergens but not to acarid allergens. Only a limited number of healthy dogs were tested in this study. A gold standard for determining the clinical relevance of IgE sensitisation does not exist. Inhibition of anti-CCD-IgE antibodies seems to be of importance to improve serum test specificity for allergen-specific IgE in atopic dogs in relation to intradermal allergy testing.