Cat Dander Research Articles

The search for still unknown pathomechanisms of allergy

In recent decades, atopic diseases, such as atopic dermatitis (AD), allergic asthma (AA), allergic rhinitis (AR), and food allergy (FA) have been estimated rapidly increasing in prevalence. These diseases are characterized by the presence of specific immunoglobulin E (sIgE) and often relate to each other and develop in sequence (the so-called “atopic march”). AD may be the first early manifestation in infants followed by FA often within the first year of life. Moreover, AD is a risk factor for developing sensitization to airborne allergens later in life that can cause clinical manifestations of AA and AR. According to the dual-allergen exposure hypothesis, allergic sensitization to food allergens is promoted through cutaneous exposure, rather than the oral route. Moreover, there is evidence that exposure to food allergens, in particular peanuts, in the airway would also lead to food sensitization. The most frequent route of sensitization for inhalant allergens is still debated. Of note, a recent case report supports the development of sensitization to cat dander through a cat bite. Our review aims to provide an overview of current knowledge and unmet needs in the pathophysiology of respiratory and FAs.

Analysis of allergen-specific IgE in children with atopic dermatitis from 2021 to 2023 in a hospital of pediatric in Tianjin City

Objective: To explore the distribution of allergen-specific IgE (sIgE) for children with atopic dermatitis in Tianjin City and provide the evidences of clinical diagnosis and treatment. Methods: A retrospective cross-sectional study was conducted to analyze the children who were suspected of atopic dermatitis and tested for serum sIgE in the Tianjin Children's Hospital from March 2021 to February 2023. Using first detection results only, a total of 1 841 serum samples were tested for twenty common allergens. The method was the enzyme-linked immune capture assay. The allergen epidemiological characteristics were statistically analyzed by Chi square test based on the children's characteristics and factors such as different sexes, ages and seasons by the mass data. Results: Among the 1 841 cases, the results showed that 1 247 (67.73%) were sensitized to at least 1 allergen-sIgE, comprising to 49.86% (918/1 841) to food allergen-sIgE and 47.96% (883/1 841) to aeroallergen-sIgE. The top three food allergens-sIgE were egg 32.10% (591/1 841), milk 25.91% (477/1 841) and wheat flour 14.61% (269/1 841); the top three positive rates of aeroallergens-sIgE were house dust 24.33% (448/1 841), alternaria 20.59% (379/1 841) and dermatophagoides farinae 14.83% (273/1 841). The positive rates of food allergens-sIgE were the highest in the 1-3 years old group (64.11%, 434/677) (χ2=122.854, P<0.001), while the positive rates of aeroallergens-sIgE were higher in the 11-14 years old group (71.26%, 62/87) (χ2=134.968, P<0.001). No seasonal difference was revealed in the overall positive rate of food allergen-sIgE and aeroallergen-sIgE (χ2=4.047, P=0.256; χ2=7.549, P=0.056). The positive rates of soybean-sIgE and milk-sIgE were the highest in summer (χ2=11.329, P=0.010; χ2=28.720, P<0.001), whereas alternaria-sIgE and mugwort-sIgE were the highest in summer and autumn, respectively (χ2=8.462, P=0.037; χ2=10.641, P=0.014). Among the 1 841 cases, 32.21% were sensitized to three or more allergens-sIgE. The sIgE concentration levels of egg, milk and house dust were mainly level 1 to 2, and the proportions of level 3 and above were all under 15%; although the positive rates of crab, shrimp, and peanut were low, the proportions of grade 3 and above were all beyond 30%. Children sensitized to alternaria, dermatophagoides farinae, mugwort, and cat dander had higher sIgE concentration levels, which were 68.07%, 49.45%, 56.57% and 47.83% respectively. Conclusions: This study can reflect the epidemic characteristics of allergen-sIgE in children with atopic dermatitis in Tianjin region to a certain extent. Allergen-sIgE positivity in patients differed by age, and there were seasonal differences and grade distribution differences in the positive rates of some allergens-sIgE. It is necessary to reasonably avoid the high-risk allergens according to the epidemiological characteristics and clinical symptoms, which provide valuable information for the prevention, diagnosis and treatment of atopic dermatitis.

Furry animal allergen components diagnosis: identification of main components and clinical management strategies

Furry animal allergens, particularly cat and dog hair and dander, are common allergens in indoor environments, affecting the health of people world widely. Key sensitizing components such as Fel d 1 from cats and Can f 1 from dogs have been extensively studied and identified by the scientific community. Component resolved diagnosis (CRD) technology in modern diagnostic methods provides an accurate way to identify and distinguish these components, which is extremely important for the prevention of furry animal allergies and the formulation of personalized treatment strategies. To enhance the understanding of furry animal component diagnosis and promote the alignment of the Chinese discipline of allergology with international standards, this article interprets and explains the content of the "Molecular Allergology User's Guide 2.0" recently released by the European Academy of Allergy and Clinical Immunology. It focuses on the epidemiological characteristics of furry animal components, the diversity of allergen protein families, and their clinical diagnosis and management.

Estudio aerobiológico en Lima, Perú. ¿Tipuana- Tipu, tal vez un nuevo alérgeno?

Introduction:Knowledge about local airborne allergens in any geographical area is essential for effective diagnosis and treatment of allergic diseases. Tipuana tipu, tree of the Fabaceae family, native from South America, it is present in the main avenues of metropolitan Lima and in some parks (big gardens) of the city. The objective was to report the Tipuana tipu pollen how a new allergen capable of triggering allergic symptoms. Methods:The pollen counts were made according to standardized technique with a Burkard seven days following the European Aerobiology Society´s Network Group recommendations.1 The trap was installed on the roof of Clinica SANNA el GOLF, San Isidro, which is 20 m high, 12°5'54"S 77°3'6"W in the west-south of the Lima urban area. The sampling period was performed from September 2020 to October 2021. Collection of Tipuana tipu pollens and Preparation of Tipuana tipu pollen extracts 1:20 w/v was done using a previously described method.2We carried out systematic skin prick testing with Tipuana tipu pollen extract and other aeroallergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis), molds (Cladosporium herbarum, Alternaria alternata, Aspergillus fumigatus, Penicillium notatum), cat and dog danders, Periplaneta americana, grass 6 mix, weed mix (Inmunotek, Spain) on 80 patients (18 to 50 years) seen in our allergy center, they suffering from November to January rhinitis and/or conjunctivitis symptoms. The majority living near avenues and large green areas, where Tipuana trees grew. Results:We found a total of 952 grains/m3 of Tipuana tipu pollen between November 2020 to January 2021, with the maximum concentration of 37 grains/m3 on December 10th. We also found other airborne pollen Types: Poaceae, Myrtaceae, Compositae and Betulaceae.14/80 patients (17.5%) showed positive skin prick test only to Tipuana tipu extract. Most of the patients with positive tests to Tipuana extract presented symptoms of rhinoconjunctivitis during the Tipuana pollination period. Four patients showed positive skin prick test to Tipuana tipu and grass 6 mix extracts, most of the rest of our patients were sensitized to dust mites extracts (Dermatophagoides pteronyssinus).Conclusions:The west-south population of Lima urban city is exposed to Tipuana tipu pollen. We do not found previous publications about Tipuana tipu allergy. Almost 18% of the patients tested in our sample were mono-sensitized to this pollen. The results of this study should be compared with data from the forthcoming years, to identify seasonal and annual fluctuations, extend the traps to other locations in Lima, and of course try to standardize and improve the Tipuana tipu pollen extract.

Senzibilizacija na inhalacijske alergene kod djece s alergijskim rinitisom

Introduction: Allergic rhinitis is an inflammatory disease of the nasal mucosa that most often occurs in children and it is a growing global health problem. Aim: Aim of the study was to examine the sensitization on inhalant allergens in children with allergic rhinitis and its association with asthma. Methods: We performed a cross-sectional study using data from our hospital records (2018-2022). A total of 412 children with symptoms of allergic rhinitis participated in the study, aged from 4 to 17 years old. The presence of allergic rhinitis was evaluated by specialist of allergology, immunology and otorhinolaryngology. The diagnosis was made on personal and family history, physical examination of the patient, skin prick tests and laboratory parameters. Results: Out of 412 children enrolled in the study, 205 (55.1%) were male. All were diagnosed with allergic rhinitis, while 168 (40.78%) were, in addition to allergic rhinitis, diagnosed with bronchial asthma 66.26% (N=273). Hypersensitivity to the inhalant allergens according to positive skin prick test was found as follows: Dermatophagoides pteronyssinus (67.96%; N=280 subjects), Ambrosia artemisiifolia (62.87%; N=259 subjects), Betula (54.13%; N=223 subjects) Corylus (52.91%; N=218) and grass pollen (52.91%; N=218 subjects).Hypersensitivity to the inhalant allergens according to higher levels of specific IgE was found as follows: Dermatophagoides pteronyssinus (66.26%; N=273), Ambrosia artemisiifolia (66.02%; N=272), Betula (57.52%; N=237), Corylus (55.34%; N=228), Poa pratensis (45.39%; N=187), Artemisia vulgaris (27.67%; N=114), Phelum pratense (25.46%; N=105), cat dander (28.64%; N=118) and dog dander (23.54%; N=87). Conclusion: Our data suggest that sensitization on house dust mite has important role in development of allergic rhinitis. Most children have allergic rhinitis linked to asthma.

Gut microbiome signature and nasal lavage inflammatory markers in young people with asthma

BackgroundAsthma is a complex disease and a severe global public health problem resulting from interactions between genetic background and environmental exposures. It has been suggested that the gut microbiota may be related to asthma development, however, such relationships needs further investigation. ObjectiveThis study aimed to characterize the gut microbiota as well as the nasal lavage cytokine profile of asthmatic and non-asthmatic individuals. MethodsStool and nasal lavage samples were collected from 29 children and adolescents with Type 2-asthma (defined as asthma with >2.5% eosinophils in sputum, and a positive skin prick test) and 28 children without asthma in Brazil. Amplicon sequencing of the stool bacterial V4 region of the 16S rRNA gene was performed using Illumina MiSeq. Microbiota analysis was performed using QIIME2 and PICRUST. Type 2-asthma phenotype was characterized by high sputum eosinophil counts and positive skin prick tests for house dust mites, cockroaches, cat or dog dander. The nasal immune marker profile was assessed using a customized multiplex panel. ResultsThe stool microbiota differed significantly between asthmatic and non-asthmatic participants (p=0.001). Bacteroides was more abundant in participants with asthma (p<0.05), while Prevotella was more abundant in non-asthmatics (p<0.05). In asthmatics, the relative abundance of Bacteroides correlated with IL-4 concentration in nasal lavage. Inference of microbiota functional capacity identified differential fatty acid biosynthesis in asthmatics compared to non-asthmatics. ConclusionThe stool microbiota differed between asthmatics and non-asthmatics in young people in Brazil. Asthma was associated with higher Bacteroides which correlated with nasal IL-4 concentration.

Factors contributing to the diagnosis and onset prediction of perennial allergic rhinitis in high-risk children: A sub-analysis of the CHIBA study

BackgroundThis study aimed to clarify the diagnostic and predictive factors for perennial allergic rhinitis (PAR) onset in children by analyzing the results of the Chiba High-risk Birth Cohort for Allergy study, which examined newborns with a family history of allergies. MethodsOverall, 306 pregnant women were recruited. Their newborns were examined by otolaryngologists and pediatric allergists at 1, 2, and 5 years of age. Participants with clinical and laboratory data available at all consultation points were considered eligible. ResultsAmong 187 eligible participants, the prevalence rates of PAR were 2.1%, 4.3%, and 24.1% at 1, 2, and 5 years of age, respectively. AR-specific nasal local findings and eosinophils in nasal smear were observed in a substantial number of patients with PAR at 1 and 2 years of age. Factors present up to 2 years of age that were associated with PAR onset at 5 years of age, in descending order, were as follows: sensitization to house dust mites (HDM), nasal eosinophilia, and sensitization to cat dander. In 44 cases with HDM sensitization, nasal eosinophilia up to 2 years of age achieved a sensitivity of 76.0% and a specificity of 73.7% for predicting PAR onset at 5 years. ConclusionsRhinitis findings and nasal eosinophilia are useful auxiliary diagnostic items for pediatric PAR. Sensitization to HDM and nasal eosinophilia were the most influential factors associated with future PAR onset. A combination of these factors may facilitate the prediction of PAR onset.

Aerobiological study in Lima, Perú. ¿Tipuana-Tipu, perhaps a new allergen?

To report the Tipuana tipu pollen as a new allergen capable of triggering allergic symptoms. The pollen counts were made according to standardized technique with a Burkard seven days following the European Aerobiology Society´s Network Group recommendations.1 The trap was installed on the roof of Clinica SANNA, El Golf, San Isidro, which is 20 m high, 12°5'54"S 77°3'6"W in the west-south of the Lima urban area. The sampling period was performed from September 2020 to October 2021. Collection of Tipuana tipu pollens and Preparation of Tipuana tipu pollen extracts 1:20 w/v was done using a previously described method.2 We carried out systematic skin prick testing with Tipuana tipu pollen extract and other aeroallergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis), molds (Cladosporium herbarum, Alternaria alternata, Aspergillus fumigatus, Penicillium notatum), cat and dog danders, Periplaneta americana, grass six mix, weed mix (Inmunotek, Spain) on 80 patients (18 to 50 years old) seen in our allergy center, they suffering from november to january rhinitis and/or conjunctivitis symptoms. The majority living near avenues and large green areas, where Tipuana trees grew. We found a total of 952 grains/m3 of Tipuana tipu pollen between November 2020 to january 2021, with the maximum concentration of 37 grains/m3 on December 10th. We also found other airborne pollen Types: Poaceae, Myrtaceae, Compositae and Betulaceae. 14/80 patients (17,5%) showed positive skin prick test only to Tipuana tipu extract. Most of the patients with positive tests to Tipuana extract presented symptoms of rhinoconjunctivitis during the Tipuana pollination period. Four patients showed positive skin prick test to Tipuana tipu and grass 6 mix extracts, most of the rest of our patients were sensitized to dust mites' extracts (Dermatophagoides pteronyssinus). The west-south population of Lima urban city is exposed to Tipuana tipu pollen. We do not foud previous publications about Tipuana tipu allergy. Almost 18% of the patients tested in our sample were mono-sensitized to this pollen. The results of this study should be compared with data from the forthcoming years, to identify seasonal and annual fluctuations, extend the traps to other locations in Lima, and of course try to standardize and improve the Tipuana tipu pollen extract.

Aeroallergen sensitization patterns in children with allergic rhinitis from Guangzhou and Liuzhou in southern China

&lt;sec&gt;&lt;title&gt;Background&lt;/title&gt;&lt;p&gt;The sensitization patterns of allergic rhinitis (AR) to allergens exhibit global variations, influenced by diverse geographical, climatic, cultural, and genetic determinants. We aimed to contrast the allergen profiles among children belonging to distinct ethnic groups residing in two disparate provinces of China, with the objective of elucidating the impact of environmental and genetic factors on the types of allergens.&lt;/p&gt;&lt;/sec&gt;&lt;sec&gt;&lt;title&gt;Methods&lt;/title&gt;&lt;p&gt;A comparative analysis was conducted on allergen sensitizations among children with allergic rhinitis (AR) in Guangzhou and Liuzhou from 2019 to 2023. The specific IgE response to a range of inhalant allergens was evaluated utilizing the ImmunoCAP 100 system. Statistical analysis was conducted using the SPSS 20 software package. For comparisons, the Chi-square test or Fisher's exact test was employed, depending on the nature of the data and the assumptions of each test.&lt;/p&gt;&lt;/sec&gt;&lt;sec&gt;&lt;title&gt;Results&lt;/title&gt;&lt;p&gt;A total of 9684 AR children from Guangzhou and 1679 from Liuzhou were enrolled in the study. Notably, the sensitization rates toward D. &lt;italic&gt;farinae&lt;/italic&gt;, &lt;italic&gt;D. pteronyssinus&lt;/italic&gt;, cat dander, dog dander, common ragweed, and mugwort were significantly elevated in Guangzhou compared to Liuzhou. However, the sensitization rates to cockroaches exhibited no notable disparities between the two cities.&lt;/p&gt;&lt;/sec&gt;&lt;sec&gt;&lt;title&gt;Conclusions&lt;/title&gt;&lt;p&gt;The allergen composition in AR children is similar between Guangzhou and Liuzhou, with &lt;italic&gt;D. farina&lt;/italic&gt; and &lt;italic&gt;D. pteronyssinus&lt;/italic&gt; as the main allergens. However, the sensitization rates of all allergens except for cockroaches in Guangzhou are higher than those in Liuzhou. Our results suggest that the causes of allergen sensitization are complex, and genetic and environmental factors cannot be ignored.&lt;/p&gt;&lt;/sec&gt;

Retrospective Analysis of Allergen Distribution Dynamics in Central Taiwan.

Introduction: Allergy is a type Ⅰ hypersensitivity reaction to certain substances (allergens) such as environmental factors, food and drugs. Allergies are a significant public health issue, and therefore, understanding the distribution patterns of allergens in specific regions is important. This study aimed to retrospectively analyse allergen distribution patterns in Central Taiwan over a 5years period (2018-2022). Methods: Data of patients who had allergen sensitization testing using the OPTIGEN® Allergen-Specific IgE Assay from the 1st of January 2018 to the 31st of December 2022 were reviewed retrospectively. Statistical analyses were performed to determine the prevalence and distribution of allergens in our study population. Results: A total of 8,444 patients (3,784 males and 4,660 females) who attended the Asia University Hospital for allergen detection were enrolled in this study. Dermatophagoides farina (41.8%), Dermatophagoides pteronyssinus (37.9%), house dust (24.6%), cockroach mix (17.7%), crab (12.6%), clam (9.8%), shrimp (9.1%), cat dander (8.1%), pig weed (8%) and peanut (7.8%) were identified as the ten allergens that most commonly induced sensitization in our study population. Additionally, crab, clam, shrimp, peanut and beef were the five most common food allergens. Conclusion: In summary, our findings contribute significantly to the knowledge on allergen distribution in Central Taiwan. Our identification of prevalent allergens may contribute to an improved understanding of the epidemiology of allergies in this region.

Clinical characteristics in Japanese patients with chronic rhinosinusitis who underwent endoscopic sinus surgery

ObjectiveThere is heterogeneity in the pathophysiology of chronic rhinosinusitis (CRS). Obtaining a detailed understanding of patient profiles in specific regions can provide valuable information not only for clinical practice but also future research plans. The aim of this study was to investigate the characteristics of patients who underwent endoscopic sinus surgery (ESS) for CRS. MethodsThis retrospective, single-center study examined the features of 453 patients with CRS who underwent ESS in the Tokyo area of Japan. The study evaluated various factors in patients with CRS including sex and age, the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis (JESREC) score, the recurrence rate of CRS, comorbidities of asthma and/or allergic diseases, and IgE sensitization to 12 inhaled allergens. ResultsAge-related declines in the sensitization rate to inhaled allergens were observed, and the most notable age-related decrease in specific IgE antibodies was observed for house dust mites (HDM) (p = 8.3 × 10−7). Sensitization to HDM, cat dander, and various types of fungi, including Aspergillus, was frequently observed in the CRS with asthma group, with rates of 54%, 17%, and 17%, respectively. We found that 23% of the patients had recurrence. In the recurrence group, the positive rates of specific IgE antibodies for birch and cat dander were significantly higher than in the no recurrence group. Bronchial asthma was identified as an important factor for recurrence. Among male patients, the recurrence group was younger than the no-recurrence group (p = 0.0032). Severe eosinophilic CRS (ECRS) showed early recurrence after surgery, with over the half of the patients experiencing at least one recurrence within 2 years post-surgery. Among patients with ECRS, the recurrence rate for females was 1.92 times higher than for males. ConclusionOur study revealed the influences of age and sex on various clinical phenotypes of CRS patients undergoing ESS. There was a high sensitization rate to cat dander in both the recurrence and asthma groups. Further research on diverse disease etiologies is necessary to improve therapeutic strategies for patients with CRS.

B-058 Development and Evaluation of the Assay for Detection of Human Specific IgE Against Animal Dander Allergens on a Fully Automated Chemiluminescence Immunoassay Platform—Autolumo® A2000 Plus

Abstract Background The detection of specific IgE is a key method for diagnosing allergic diseases. An accurate, user friendly and cost-effective way to clinically diagnosing allergies is beneficial for the patients. Our detection kit together with the Autolumo A2000 Plus chemiluminescence fully automated platform provide a new and more effective (40 minutes) way for detection of specific IgE with simple operation, high sensitivity and specificity. Methods The Animal Dander Allergen Mix Assay kit detects specific IgE against cat dander (E1), horse dander (E3), cow dander (E4) and dog dander (E5). Performance evaluation of the animal dander mix, E1, E3, E4 and E5 assay kits for the detection of specific IgE in serum was performed on our automated chemiluminescence platform (Autolumo A2000 Plus) and compared to a well-characterized platform (ImmunoCAP, Phadia). During detection, magnetic particle suspension, antigen solution, patient sample, and enzyme conjugate were added sequentially. A streptavidin-biotinylated antigen-sIgE antibody-anti-IgE-HRP conjugate complex is formed, wherein the amount of the anti-IgE-HRP conjugate is positively correlated to the amount of sIgE antibodies in the patient sample. After the substrate is added, the HRP catalyze the chemical reaction to generate a recordable signal in the form of light. The intensities of the light were obtained by using a chemiluminescence quantitative analyzer, and the standard curve was generated according to the 7-point calibration, and then the sIgE antibody concentrations in the serum sample were analyzed. The overall agreement, method comparison, precision, linearity, and stability of our mixed and single assay kits were evaluated using serum samples (n &amp;gt; 140) that had been characterized with Phadia. Results The overall agreement for the animal dander mix assay is 91.84%, with the average intra-run and inter-run precision to be 1.97% and 4.21% respectively. The limit of blank (LoB) and limit of detection (LoD) for the animal dander mix assay is 0.019 kU/L and 0.045 kU/L respectively. The sensitivity for our single E1, E3, E4, and E5 assays are 97%, 85.6%, 70.8%, and 80.2%, respectively. All single assays have a specificity &amp;gt;90%, total precision &amp;lt;5% CV, and a linearity with R2 &amp;gt; 0.999. The LoB, LoD and recommended LoQ for all single assays are 0.019 kU/L, 0.037 kU/L, and 0.1 kU/L respectively. The average signal drifts after 10 days incubation in 37C is less than 10% indicating the assays are stable. Conclusion Autolumo A2000 Plus is a fully automated chemiluminescence Immunoassay platform that provides accurate and cost-effective screening for allergy diagnostics with excellent overall agreement, precision, and stability.

A study of allergen detection panel in Guangzhou, southern China based on real-world data from the past 7 years

This study aims to reduce the cost of allergen testing for Guangzhou, China by limiting the number of allergens for which patients are tested, and provide a testing panel to improve diagnostic and therapeutic efficiency. This retrospective study of real-world data from 2012 to 2019 included 39,570 patients with suspected allergies in Guangzhou, southern China. All the patients were tested for one or more of the following allergens serum specific immunoglobulin E (sIgE): Dermatophagoides pteronyssinus, Dermatophagoides farinae, cat dander, dog dander, Artemisia vulgaris, Aspergillus fumigatus, Alternaria alternata, Blattella germanica, egg whites, milk, wheat, peanuts, soybeans, Cancer pagurus, and Penaeus monodon by PhadiaCAP 1000. Totally, only the positive rates of allergens sIgE in D. farinae, D. pteronyssinus, milk, egg whites, B. germanica, C. pagurus, A. alternata, and P. monodon were > 10%, the other allergens were between 4–7%. Moreover, among the allergic diseases, dust mites exhibited the overall highest positive rate, followed by milk and B. germanica. In children, milk was the main allergen, whereas in adults, mites, cockroaches, shrimp, and crab allergens had higher positive rates. The optimal scale analysis shows that the multiple sensitization classification of patients can be divided into three categories: I D. farinae and D. pteronyssinus; II. C. pagurus, P. monodon, and B. germanica; III. Milk and egg whites. Generally, a panel including 4 allergens can detect > 90% of the potential allergy in this local population. In Guangzhou, southern China, D. farinae, milk, B. germanica, and A. alternata as a panel screening allergy for suspected allergic patients was suggested base on this study.

Allergen-specific IgE in the tear fluid of Chinese patients with common allergic conjunctivitis in autumn and winter.

In this study, we determined the positive rates of allergen-specific immunoglobulin E (IgE) in the tear fluid of Chinese patients with common allergic conjunctivitis (AC) in autumn and winter, compared systemic and ocular allergen tests, and explored the correlation between the numbers and categories of allergens and clinical AC features. This cross-sectional study recruited 44 patients with AC (86 eyes). Specific IgEs for allergens common in China (house dust mite, cat/dog dander, mugwort/ragweed pollen, cottonwood/willow/elm pollen, milk, egg whites, soybeans) were measured in collected tears using kits for allergen-specific IgE antibodies. AC signs and symptoms were graded according to severity. Specific IgE in tears was positive in 87.2% of eyes. House dust mite was the most common allergen (86.0%), followed by cat (24.4%) and dog (7.0%) dander; tree and grass pollen accounted for only 4.7% and 2.3%, respectively. Food allergens were not detected. The positive rates of the systemic allergen tests were lower than in tear fluid tests in both eyes, especially for house dust mites (P = 0.000). In patients with more allergens, itching was more severe (P = 0.035), while conjunctival hyperemia was milder (P = 0.002). In autumn and winter, the most common AC allergen in Chinese patients was house dust mites. Compared with systemic allergen tests, measuring specific IgE in tears may be a non-invasive method to diagnose and evaluate AC severity, which may be more suitable to reflect the local conditions of ocular surface inflammation due to its high positive rate and convenience.

TiO2-Photocatalyst-Induced Degradation of Dog and Cat Allergens under Wet and Dry Conditions Causes a Loss in Their Allergenicity.

Allergies to dogs and cats can cause enormous damage to human health and the economy. Dog and cat allergens are mainly found in dog and cat dander and are present in small particles in the air and in carpets in homes with dogs and cats. Cleaning houses and washing pets are the main methods for reducing allergens in homes; however, it is difficult to eliminate them completely. Therefore, we aimed to investigate whether a TiO2 photocatalyst could degrade dog and cat allergens. Under wet conditions, exposure to the TiO2 photocatalyst for 24 h degraded Can f1, which is a major dog allergen extracted from dog dander, by 98.3%, and Fel d1, which is a major cat allergen extracted from cat dander, by 93.6-94.4%. Furthermore, under dry conditions, the TiO2 photocatalyst degraded Can f1 and Fel d1 by 92.8% and 59.2-68.4%, respectively. The TiO2 photocatalyst abolished the binding of dog and cat allergens to human IgE by 104.6% and 108.6%, respectively. The results indicated that the TiO2 photocatalyst degraded dog and cat allergens, causing a loss in their allergenicity. Our results suggest that TiO2 photocatalysis can be useful for removing indoor pet allergens and improving the partnership between humans and pets.

Sensitization patterns to cat molecular allergens in subjects with allergic sensitization to cat dander.

The use of molecular allergology has increasingly become common in the diagnosis and management of allergic diseases. However, there is still a lack of data on cat molecular allergens in adults. Therefore, we aimed to uncover the sensitization patterns to cat molecular allergens. Participants were recruited from the West Asthma Sweden Study, a population-based study enriched with asthma subjects aged 16-75years. Of 1872, 361 individuals were positive for cat dander immunoglobulin E and were further analysed for cat molecular allergens (Fel d 1/2/4/7). Sensitization patterns were classified as monosensitization, polysensitization, and concomitant sensitization, and were related to demographic and clinical measurements. Among cat-sensitized subjects, 84.2% were sensitized to secretoglobin, while 42.4% were sensitized to lipocalins. Nearly half of the subjects were monosensitized to Fel d 1. Polysensitization was observed in 20.2%, and concomitant sensitization to protein families was seen in 7.2%. Asthma prevalence, cat exposure, and rural living were associated with poly- and concomitant sensitization to protein families. Concomitant sensitization to single allergens was more common in those with asthma than in those without, while concomitant sensitization to both Fel d 1 and Fel d 4 was the most common pattern in individuals with asthma. Sensitization patterns also differed according to cat ownership and the degree of urbanization. Sensitization to molecular allergens was observed in 90.9% of cat-sensitized subjects and showed variations across participants' background characteristics and the presence of asthma. Identification of sensitization patterns to cat allergens might provide better characterization of cat-allergic subjects.

Establishment of a homogeneous chemiluminescence immunoassay for cat dander sIgE antibody detection

Background In vitro specific IgE (sIgE) testing has become an important tool for the diagnosis of IgE-mediated allergic diseases. Current methods used to detect allergen sIgE are time consuming and/or expensive. Therefore, a new method was developed for rapid quantitative detection of cat dander-sIgE antibody based on homogeneous chemiluminescence immunoassay. Methods Selection of chemibeads with different chemical groups, and the best Light-initiated chemiluminescence assay (LiCA) analytical mode for cat dander-sIgE detection. To validate and eliminate the interference of IgE on the detection of cat dander-sIgE, concentration of biotinylated anti-human IgE antibody was optimized. For quantification of cat dander-sIgE, a calibration curve was established, and the performance of the assay was evaluated according to clinical guidelines. Results Indirect LiCA is the best mode of analysis and biotinylated anti-human IgE antibody at a dilution ratio of 1:250 minimizes IgE interference. The coefficient of variation of the developed LiCA was 1.49% to 4.66%, with an intermediate precision of 6.90% to 8.21%. The LoB, LoD, and LoQ of the assay were 0.023 kUA/L, 0.056 kUA/L and 0.185 kUA/L. The coefficient of correlation (r) between LiCA and ImmounoCAP was 0.9478. Conclusions A cat dander-sIgE quantitation assay based on homogeneous chemiluminescence immunoassay was established, which could be a new reliable analytical tool for the determination of cat dander-sIgE.

Indoor-air purification by photoelectrochemical oxidation mitigates allergic airway responses to aerosolized cat dander in a murine model

Portable air purifiers help improve indoor air quality by neutralizing allergens, including animal dander proteins. However, there are limited in-vivo models to assess the efficacy of these devices. Here, we developed a novel animal model of experimental asthma using aerosolized cat dander extract (CDE) exposure and compared the efficacy of select air purification technologies. Mice were exposed to CDE aerosols for 6 weeks in separate custom-built whole-body exposure chambers equipped with either a photoelectrochemical oxidative (PECO) Molekule filtration device (PFD) or a HEPA-assisted air filtration device (HFD) along with positive (a device with no filtration capability) and negative controls. Compared to the positive control group, the CDE-induced airway resistance, and plasma IgE and IL-13 levels were significantly reduced in both air purifier groups. However, PFD mice showed a better attenuation of lung tissue mucous hyperplasia and eosinophilia than HFD and positive control mice, indicating a better efficacy in managing CDE-induced allergic responses. Cat dander protein destruction was evaluated by LCMS proteomic analysis, which revealed the degradation of 2731 unique peptides on PECO media in 1 h. Thus, allergen protein destruction on filtration media enhances air purifier efficacy that could provide relief from allergy responses compared to traditional HEPA-based filtration alone.

Disease and Quality of Life Aspects of Cat Allergy in Non-Pet Owners with Allergic Rhinitis

Introduction: The severity of cat allergy-related symptoms varies widely. The rising prevalence of cat owning makes it a significant human health problem. The aim of this study was to evaluate disease severity and quality of life (QoL) aspects of cat sensitization and allergy in non-pet owners with allergic rhinitis (AR). Methods: In this study, 231 out of 596 patients with AR were enrolled. The disease severity and QoL measures of the non-pet owner patients were evaluated according to their demographics and allergen sensitizations. The data were re-gathered after cat exposure for cat-sensitized patients (n = 53). Results: The median age of the patients (174 females, 57 males) was 33 (18–70). The overall frequency of cat sensitization was 12.6% (75/596). The frequency of cat allergy in this cohort was 13.9% (32/231). Family history of atopy and multi-allergen sensitization were more common in the cat-sensitized patients. Disease severity and QoL scores were higher in the cat allergy group after cat exposure. Cat allergy was the major independent risk factor for the severity of AR and QoL measures. Conclusion: Due to the fact that indirect exposure to cat dander allergens can occur anywhere, even where cats are not present, cat-sensitized people should be aware of cat allergy. Cat allergy appears to be an independent risk factor for disease severity and QoL effects for non-pet owner patients with AR.

Evaluating Non-IgE-Mediated Allergens’ Immunoreactivity in Patients Formerly Classified as “Intrinsic” Asthmatics with Help of the Leukocyte Adherence Inhibition Test

Background: The ancient concept of “intrinsic” and “extrinsic” asthma has evolved in line with growing scientific knowledge and the use of new clinical diagnostic tools. Objective: The present study aims to evaluate the non-IgE-mediated immunoreactivity against common allergens, in asthmatic patients without evidence of IgE-mediated hypersensitivity against these allergens. Methods: A group of 127 “intrinsic” asthmatic outpatients, were submitted to ex vivo Leukocyte Adherence Inhibition Tests (LAIT) with extracts of Dermatophagoides pteronyssinus, Hevea brasiliensis latex, dog dander, cat dander, cow’s milk proteins, beekeeping pollen and a mixture of fungal extracts. Results: Cascade graphs were assembled according to the distribution of the LAIT results among the range of results of Leukocyte Adherence Inhibition (LAI) inside each group. A column graph was plotted with the mean LAI results for each antigen. The non-parametric Wilcoxon-Mann-Whitney U-test performed between the results of each test was significant only between the results of the LAIT performed with the dog extract and the mixed fungal extract (U = 1,179.5; the z-score was -2.64109; the p-value was 0.0083). All other Wilcoxon-Mann-Whitney U-test calculations between LAIT performed with the other allergens were not significant at p &lt; 0.01. Conclusion: The evidence of non-IgE-mediated immunoreactivity in allergic patients has been reported in the medical literature since the beginning of the 19th century and has been increasing since then. This descriptive article presents the contribution of the LAIT as a tool to quantify the overall non-IgE-mediated cellular/humoral immunoreactivity against common allergens in patients formerly classified inside the “intrinsic” asthma endotype.