Cat Dander Research Articles

Clinical profile and skin prick test analysis in children with allergic rhinitis of North Kerala, India

Background: Allergic rhinitis (AR) is increasing in prevalence among children globally and in India. Allergens are factors which trigger allergic rhinitis. Skin prick test (SPT) is a rapid, sensitive and cost effective test to detect IgE- mediated allergic diseases. Identification of common aeroallergens in an area is necessary, in order to educate the patient on what allergens to avoid and also help find the best formulation of allergen immunotherapy for effective AR treatment. This study was done to find the clinical profile and skin sensitivity to common allergens by skin prick test in children with allergic rhinitis between six and fifteen years.Methods: This cross-sectional study was conducted for a period of one year from January 2016 to December 2016. All children between 6 to 15 years with allergic rhinitis were included in the study. Skin prick test was done with seven most common allergens.Results: A total of 60 children with allergic rhinitis were studied and 42 patients (70%) tested positive for SPT. The major symptoms were persistent sneezing (68%), nasal itching (33%), rhinorrhea (85%) and nasal congestion (42%). The proportion of sneezers-runners was higher than blockers (64% versus 36). We tested seven common allergens and house dust mite allergen yielded the highest number of positive responses (33%) followed by cockroach (25%), alternaria (16.66%), parthenium (10%), cat dander (8.35%), sorghum (5%) and dog dander (5%). Among patients with SPT positivity; eight were positive to one allergen, thirteen were positive to two allergens, sixteen to three allergens and five to four allergens.Conclusions: Allergic Rhinitis with a number of allergic co morbidities has a significant impact on the quality of life and scholastic performance in children. Skin prick test which is a standardized, most rapid, sensitive and cost-effective test to detect IgE-mediated allergic diseases is helpful in identifying the common allergens. House dust mite is the commonest allergen tested positive in our study in children.

Cat dander extract directly stimulates BAFF-dependent class switch recombination to IgE in B cells without T-cell help

Cat dander extract directly stimulates BAFF-dependent class switch recombination to IgE in B cells without T-cell help

Development of a Method to Evaluate Cat Dander Levels by Safranin-O Staining

Development of a Method to Evaluate Cat Dander Levels by Safranin-O Staining

Fel d1 and Fel d4 Fur, Urine and Saliva Levels in Domestic Cats

Introduction: Sensitization to cat dander is associated with an increased risk of asthma and rhinitis. The majority of patients with cat allergy have IgE to Fel d1 but recent reports indicate that some react to Fel d4. There is little information about Fel d4 levels in cats. Objectives: The purpose of this study was to evaluate Fel d4 in fur, saliva and urine of cats in comparison with Fel d1. Methods: Cats coming for general surgical procedures at a local animal hospital were recruited for this study. Owners volunteered their cats and signed an informed consent prior to any sample collection. Fur, urine and saliva samples were obtained from male and female cats of various breeds and ages. Commercially available ELISA kits were used to measure Fel d1 and Fel d4. Results: The study included 26 cats, 13 male, 13 female, age 5.6 ± 4.3 years (mean ± SD). Fur was obtained from all cats; urine and saliva from 20 and 17 cats, respectively. Urine Fel d1 (0.02, 0.065-0.071 ug/ml, median, 25-75 percentile) and Fel d4 ( Conclusions: This study demonstrates that, in cats, saliva is the main source of Fel d4 while fur is the main source for Fel d1. It is possible that levels of Fel d4 in fur arise from saliva deposited when grooming rather than from secretion from the sebaceous glands.

Development and characterization of an allergoid of cat dander for immunotherapy

BackgroundAllergy to cats is a frequent cause of sensitization to indoor allergens and currently there are few alternatives to specific immunotherapy with cat native extracts. The objective is to develop and characterize a new allergoid to increase the tools available for use in clinical practice. MethodsThe allergoid cat dander extract (ACD) was developed from a native cat dander extract (NCD) by modification with glutaraldehyde, and the optimal process control was determined by SDS-PAGE, DOT BLOT and determination of free amine groups. The ACD was characterized in protein profile by SDS-PAGE, size exclusion chromatography (SEC) and peptide footprint. The allergenic profile of ACD was determined by immunoblot, IgE CAP inhibition and IgG competition ELISA. The major allergen content in NCD was obtained by the ELISA sandwich protocol and was extrapolated to ACD. ResultsThe control process determined the optimal development of the allergoid. The ACD obtained contains 182.28μg/mg of protein and 11.90μg/mg of Fel d 1. SDS-PAGE and SEC confirmed the presence of high molecular weight proteins in ACD, and the peptide footprint showed the presence of Fel d 1 and Fel d 7. The high degree of polymerization was evidenced with the determination of the reduction of lysine residues in the allergoid, resulting 91.96%. The ACD showed a significant loss of allergenicity respect to NCD, while the IgG-binding capacity was maintained. ConclusionsThe ACD obtained presents a good safety profile, so would be a good alternative for treatment of cat allergy.

The importance of specific IgE antibodies in epidemiology of allergic rhinitis and asthma - the Epidemiology of Allergic Diseases in Poland (ECAP) survey: part one. Influence of allergy risk factors on concentration of specific IgE antibodies in serum.

IntroductionSpecific immunoglobulins E (sIgE) are important parameters to estimate severity of allergic diseases.AimTo determine the influence of allergy risk factors on the concentration of specific IgE antibodies in serum.Material and methodsThe concentration of sIgE antibodies against allergens Dermatophagoides pteronyssinus, cat dander, timothy grass, Alternaria alternata were determined in serum of 4077 respondents randomly selected from 9 regions (ECAP study). The positive results of sIgE (≥ 0.35 IU/ml) were correlated to answers in questionnaires ECRHSII and ISAAC.ResultssIgE are more frequently detected in respondents declaring an allergic disease of a father than of a mother (D. pteronyssinus p < 0.05, A. alternata p < 0.01). An early beginning to attend school, kindergarten or nursery increases the frequency of sIgE detection (p < 0.05). If the number of children who slept in the same room as a respondent before the respondent was five years old, was lower, sIgE antibodies are more frequently detected (p < 0.05). Relating to: 1) all 4 allergens, sIgE are the most frequently detected in respondents declaring absence of a carpet/rug at home (p < 0.05), 2) cat dander – less frequently detected in respondents who have a cat at home at the age of 1–4 years (p < 0.005).ConclusionsCarpets/rugs capture a portion of mite, epidermal, mould allergens located at home, wherefore absence of a carpet or rug causes greater stimulation of an immune system by these allergens; as a consequence, IgE antibodies are the most frequently detected in respondents. Household contacts of the respondents, at the age of 1–4 years, with cats induced partial immune tolerance to cat dander.

Accuracy of serum-specific IgE test with microfluidic array enzyme-linked immunosorbent assay for diagnosing inhalant allergen sensitization in asthma and/or rhinitis allergy patients in Jakarta, Indonesia.

BackgroundAsthma and allergic rhinitis are a global health burden. Inhalant allergens worsen the symptoms and clinical manifestations of asthma and allergic rhinitis. Skin prick test is the gold standard for diagnosing allergen sensitization but is associated with some limitations. In contrast, in vitro serum-specific immunoglobulin E (SSIgE) test is convenient and is not associated with an anaphylactic risk.ObjectiveThe present study compared the accuracy of the SSIgE test by using microfluidic array enzyme-linked immunosorbent assay (ELISA) with that of the skin prick test for diagnosing inhalant allergen sensitization in patients with asthma and/or allergic rhinitis.MethodsThis diagnostic study included patients with asthma and/or allergic rhinitis. Of these, 100 patients underwent the SSIgE test for diagnosing sensitization to house dust mites (Dermatophagoides pteronyssinus, Dermatophagoides farinae, and Blomia tropicalis), dog dander, cat dander, and cockroach allergen. All the patients also underwent the skin prick test for diagnosing allergen sensitization. The sensitivity, specificity, predictive value, and likelihood ratio (LR) of the SSIgE test were evaluated for each allergen.ResultsSensitivity of the SSIgE test for diagnosing house dust mite sensitization was 48%–77%, with the highest sensitivity (77%) observed for diagnosing D. farinae sensitization. Specificity of the SSIgE test for diagnosing house dust mite sensitization was 64%–95%, with the highest specificity (95%) observed for diagnosing B. tropicalis sensitization. Although the SSIgE test showed high specificity and LR+ for diagnosing cockroach allergen sensitization, it showed low sensitivity (12%). Moreover, the SSIgE test showed high specificity (89%) but low sensitivity (3%) for diagnosing dog dander sensitization and high specificity (88%) but low sensitivity (10%) for diagnosing cat dander sensitization.ConclusionThe SSIgE test using microfluidic array ELISA shows moderate accuracy for diagnosing house dust mite sensitization and low accuracy for diagnosing cockroach allergen and dog and cat dander sensitization.

Common aeroallergens among children with allergies in the United Arab Emirates

Aim: The aim of this study was to determine the most common allergens that cause sensitization in skin prick tests (SPTs). Subjects and Methods: The data for this retrospective cross-sectional study were collected from results in 180 patients referred to our clinic with allergic rhinitis (AR), asthma, or atopic dermatitis (AD). All participants underwent SPT during 2013–2015 in our clinic at University Hospital Sharjah. SPT was performed with 15 aeroallergens selected based on the most common identifiable allergens in the region. A mean wheal diameter of at least 3 mm greater than the negative control was considered positive. Statistical analysis was done through SPSS 21. Results: The patients' ages ranged from 12 months to 16 years. About 69.4% had AR, 52.2% had asthma, and 21.1% had AD. Among positive patients, 89.4% were polysensitized and 10.6% were single sensitized. House dust mites (HDMs) yielded the highest prevalence of sensitization, followed by cat dander and feather mix (both 17.2%). The least common of all indoor aeroallergens was cockroach (8.9%). Molds yielded the following sensitization rates: Alternaria alternata 26.1%, Cladosporium mix 20.00%, and Aspergillus mixture 17.8%. Among outdoor allergens, sensitization rates were 21.1% for Phleum pratense, 17.2% for Russian thistle, 14.4% for Chenopodium album, and 10.0% for date palm. The least common outdoor allergen was Bermuda grass with a percentage sensitization of 5.6%. Conclusions: The most common aeroallergens identified by SPT in our allergy clinic were HDMs in all allergic diseases, which is consistent with results from similar studies in our region. The most common allergic disease in our population was AR.

Allergen-specific IgE and IgG4 patterns among patients with different allergic diseases

Background In addition to allergen-specific IgE (sIgE), allergen-specific IgG4 (sIgG4) antibodies are also involved in the immune response resulting from an allergen exposure. The aim of our study was to analyze sIgE and sIgG4 patterns in the most common allergic disorders: bronchial asthma, upper airway disorders and atopic dermatitis.Methods In this study a screening analysis of blood serum samples from 673 patients aged from 6 months to 17 years with different allergic entities was performed on microarrays. sIgE and sIgG4 levels to the most common allergens were estimated.Results sIgE response to most pollen allergens is more strongly associated with respiratory diseases than with atopic dermatitis, while sIgE responses to cat and dog dander are more strongly associated with bronchial asthma than with atopic dermatitis and upper airway disorders such as rhinosinusitis and allergic rhinitis. A lower prevalence of sIgG4 to pollen allergens in cases of atopic dermatitis is observed compared with that in cases of asthma and upper airway disorders. Analyzing all the allergic disorders, one can see that sIgG4 response to inhalant allergens is strongly associated with sensitization to the corresponding allergen.Conclusion Allergen-specific IgE and IgG4 patterns that are relevant to concrete allergic diseases differ by sIgE and sIgG4 prevalences to defined allergens.

Component-resolved microarray analysis of IgE sensitization profiles to Felis catus major allergen molecules in Russian cat-allergic patients

We aimed to determine the profile of IgE reactivity to three major cat allergens, Fel d 1, Fel d 2 and Fel d 4, in cat-allergic patients in the Moscow region in Russia. sIgE levels to recombinant proteins expressed in Escherichia coli (Fel d 1 and Fel d 4) and to Fel d 2 protein purified from cat serum were measured using a microarray method developed in our laboratory. Sera from 174 anonymous subjects with a positive reaction (≥0.35 IU/mL) to cat dander extract (e1, ImmunoCAP) and 56 negative controls were used for IgE testing. Fel d 1 was recognized by 92.5%, Fel d 2 by 29.9% and Fel d 4 by 39.1% of the tested patient sera. The sensitivity to these three proteins was approximately 98% compared to cat dander extract (correlation coefficient to ImmunoCAP is 0.94 with PPV = 0.99 and NPV = 0.95). These predictive values appeared to be even more statistically significant than the divergence between the ISAC IgE test and the extract-based singleplex ImmunoCAP. The combination of the three investigated proteins (Fel d 1, Fel d 2 and Fel d 4) is suitable for in vitro molecular (serological) diagnosis of cat allergy in this region as a complement to cat dander extract. Moreover, with this method, we found distinction between Fel d 2 and other Feline sIgEs formation.

Marijuana use is associated with hypersensitivity to multiple allergens in US adults

BackgroundThe recent legalization of marijuana use for both medical and recreational purposes in several states of the United Sates is expected to further increase the already high prevalence of marijuana use. Although allergic reactions are uncommon, the potential of marijuana use and cultivation to cause allergy should be considered. We aimed to investigate whether marijuana use is associated with the prevalence of sensitization to specific allergens. MethodsA total of 2671 adults (aged 20–59 years) who participated in the 2005–2006 National Health and Nutrition Examination Survey were included. Participants completed a questionnaire on marijuana use and underwent sensitization tests to 19 specific allergens. Those who reported marijuana use for at least 1 day in the past 30 days were considered marijuana users. ResultsNo difference was found in the history of allergy between marijuana users and non-users. Compared with marijuana non-users as a reference group, the adjusted odds ratio (AOR) of sensitization to a specific allergen among marijuana users was significantly greater for antibodies against the following: Alternaria alternata (AOR=1.67; 95% confidence interval (CI), 1.04−2.70), D. farinae (AOR=1.68; 95% CI, 1.27−2.22), D. pteronyssin (AOR=1.65; 95% CI, 1.32-2.06), ragweed (AOR=1.84; 95% CI, 1.30-2.59), rye grass (AOR=1.49; 95% CI, 1.12−1.97), Bermuda grass (AOR=1.55; 95% CI, 1.03−2.33), oak (AOR=1.76; 95% CI, 1.14−2.70), birch (AOR=2.09; 95% CI, 1.23−3.55), peanut (AOR=1.91; 95% CI, 1.25−2.92), and cat dander (AOR=1.51; 95% CI=1.13−2.03). ConclusionsWe provide preliminary findings to suggest that marijuana use is associated with sensitization to specific allergens, including molds, dust mites, plants, and cat dander.

P079 Anatomic distribution of Feld1 and Feld4 in domestic house cats

Cat dander is one of the most potent allergens. Subjects may be sensitized to several allergens in dander, but 80% of individuals have IgE antibodies to Feld1 and/or Feld4. Our purpose was to measure Feld1 and Feld4 in cat saliva, fur and urine and determine if differences depend on breed, gender, or age.

High exposure to endotoxin in farming is associated with less new-onset pollen sensitisation

ObjectivesLittle is known about risk factors for new onset and loss of atopic sensitisation in adulthood. The aim is to examine the longitudinal effect of quantitatively assessed endotoxin exposures on...

Cockroach allergen exposure and plasma cytokines among children in a tropical environment

BackgroundLittle is known about the effects of socioeconomic status or cockroach allergen on immune responses in school-age children, particularly in tropical environments. ObjectiveTo examine whether cockroach allergen and/or socioeconomic status is associated with plasma cytokine levels in Puerto Rican children. MethodsThis was a cross-sectional study of 532 children (6–14 years old) with (n = 272) and without (n = 260) asthma in San Juan (Puerto Rico). House dust allergens (cockroach [Bla g 2], dust mite [Der p 1], cat dander [Fel d 1], dog dander [Can f 1], and mouse urinary protein [Mus m 1]) were quantified using monoclonal antibody arrays. A panel of 14 cytokines (interleukin [IL]-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, interferon-γ, and tumor necrosis factor-α) was measured in plasma samples. Low household income was defined as less than $15,000 per year (below the median income for Puerto Rico in 2008–2009). Linear regression was used for the analysis of cockroach allergen and plasma cytokines. ResultsIn a multivariable analysis adjusting for low income and other allergen levels, cockroach allergen was significantly associated with decreased IL-17A and with increased levels of 8 cytokines (IL-4, IL-10, IL-17F, IL-21, IL-25, IL-31, interferon-γ, and tumor necrosis factor-α). After stratifying this analysis by cockroach allergy (ie, having a cockroach positive immunoglobulin E reaction), our findings remained largely unchanged for children sensitized to cockroach but became weaker and statistically nonsignificant for non-sensitized children. ConclusionCockroach allergen has broad effects on adaptive immune responses in school-age children in a tropical environment, particularly in those sensitized to cockroach.

Innate mechanism of pollen- and cat dander–induced oxidative stress and DNA damage in the airways

Innate mechanism of pollen- and cat dander–induced oxidative stress and DNA damage in the airways

Household pet exposure, allergic sensitization, and rhinitis in the U.S. population.

The effect of animal dander exposure on allergic sensitization may be age-dependent. A comparison between the association of the levels of exposure to pet allergen with rhinitis symptoms and allergic sensitization in children and adults is yet to be performed in the U.S. Cross-sectional study of 3034 adults (age, 20 to 85 years) and 2104 children (age, 6 to 19 years) in the National Health and Nutrition Examination Survey, 2005-2006. Samples of household dust were collected to measure the amounts of indoor allergens in the participants' homes. Self-reported rhinitis was based on symptoms during the past 12 months, and allergen sensitization was defined as a positive response to any of the 19 specific immunoglobulin E (IgE) antigens tested. Higher levels of exposure to dog dander were associated with a higher prevalence of any allergic sensitization in adults (prevalence ratio [PR] 1.19; 95% confidence interval [CI], 1.01 to 1.39), but a lower prevalence in children (PR 0.84; 95% CI, 0.73 to 0.096), p-interaction by age group 0.02. Cat exposure was associated with an increased prevalence of rhinitis symptoms in adults (PR for the 3rd vs lowest tertile of cat dander concentrations: 1.14; 95% CI, 1.05 to 1.23) but not in children (PR for the 3rd vs lowest tertile of cat dander IgE concentrations: 0.86; 95% CI, 0.70 to 1.07), p-interaction 0.01. Allergic sensitization and symptomatic response to pet dander exposure may vary based on age. Further studies are necessary to assess the mechanisms for these apparent differences.

Climate and Allergic Sensitization to Airborne Allergens in the General Population: Data from the French Six Cities Study

Background: The results of international epidemiological surveys show large geographical variations in skin test reactivity but do not provide a rationale for such variations. Objective: To assess the relationship between climate and allergic sensitization in schoolchildren. Methods: In the present study, we analyzed data from a multicenter, epidemiological survey that included 6,461 schoolchildren, aged 9-11 years, living in 6 French cities scattered around France. The protocol also included a battery of skin prick tests to common airborne allergens. The crude prevalence of sensitization to each allergen was estimated for each city and then adjusted for potential confounding factors. This analysis was repeated for monosensitization and for allergens grouped into 2 categories: indoor allergens, i.e., house dust mite (HDM), cat, and cockroach allergens, and outdoor allergens, i.e., birch pollen, grass pollen, and Alternaria. We also grouped cities according to their location on the coast, i.e., Marseille and Bordeaux, or inland, i.e., Créteil, Clermont-Ferrand, Reims, and Strasbourg. Results: A difference in prevalence of sensitization to each airborne allergen or allergens grouped into indoor and outdoor categories was found between cities, even after adjusting for potential confounding factors. Also, a higher prevalence of sensitization to HDM, cat dander, and, broadly speaking, indoor allergens, was found in children living on the coast than in those living inland, whereas they showed a lower prevalence of sensitization to birch pollen. Between-city differences in the prevalence of monosensitization were also statistically significant. Children living in coastal cities had a higher rate of monosensitization to indoor allergens and a lower prevalence of sensitization to birch pollen. The higher prevalence of allergic sensitization in children from coastal cities is most likely due to climatic conditions, such as proximity from sea and humidity. Differences in sensitization to birch allergens could be due to differential exposure to these pollen. Conclusion: These results indicate a role of environmental exposure in sensitization to perennial as well as seasonal allergens.

In vitro evidence of efficacy and safety of a polymerized cat dander extract for allergen immunotherapy

BackgroundAllergy to cat epithelia is highly prevalent, being the major recommendation for allergy sufferers its avoidance. However, this is not always feasible. Allergen specific immunotherapy is therefore recommended for these patients. The use of polymerized allergen extracts, allergoids, would allow to achieve the high allergen doses suggested to be effective while maintaining safety.ResultsCat native extract and its depigmented allergoid were manufactured and biochemically and immunochemically characterized. Protein and chromatographic profiles showed significant modification of the depigmented allergoid with respect to its corresponding native extract. However, the presence of different allergens (Fel d 1, Fel d 2, Fel d 3, Fel d 4 and Fel d 7) was confirmed in the allergoid. Differences in IgE-binding capacity were observed as loss of biological potency and lower stability of the IgE-allergen complex on surface plasmon resonance. The allergoid induced production of IgG antibodies able to block IgE-binding to native extract. Finally, studies carried out with peripheral-blood mononuclear cells from cat allergic patients showed that the allergoid induced IFN-γ and IL-10 production similar to that induced by native extract.ConclusionsCat depigmented allergoid induced production of cytokines involved in a Th1 and Treg response, was able to induce production of IgG-antibodies that blocks IgE-binding to cat native extract, and showed reduced interaction with IgE, suggesting greater safety than native extract while maintaining in vitro efficacy.

High prevalence of food sensitization among adults with allergic diseases who live in the Guadalajara metropolitan area

The prevalence of food sensitization in adults shows differences owing to geographic, regional and cultural circumstances. To identify the prevalence and factors associated with food sensitization in adults with allergic diseases. Cross-sectional study, where medical records of adult patients with any allergic disease and who tested positive to airborne allergens on at least one skin test were reviewed. Age, sex, underlying allergic disease and skin test result were recorded. Statistical analyses included food sensitization prevalence with the corresponding 95 % confidence intervals (CI), as well as a multivariate analysis to determine associated factors. We included 258 patients with a mean of 36 years of age; 75 % were of the female sex. The most common underlying condition was allergic rhinitis (59 %). The prevalence of food sensitization was 37 % (95 % CI, 31.5-43.3) and it did not vary significantly according to sex or allergic disease in question. The most sensitizing food was soybeans (44.8 %), and associated factors were sensitization to cat dander (OR = 1.8; 95 % CI, 1.03-3.2) and 5 or more positive skin tests (OR = 4.3, 95 % CI 2.3-8.1). The prevalence of food sensitization in people with allergic disease was 40 %. Further studies are required to determine its prevalence in the general population.

Prevalence of allergen sensitization in 1000 adults in Saskatchewan

BackgroundThe prevalence of sensitization varies geographically based on multiple environmental factors including humidity. The aim of this study was to determine the prevalence of atopy in symptomatic adults. More importantly we aimed to obtain a regional statistic of sensitization to common allergens given Saskatchewan’s dry climate.MethodsOne thousand consecutive symptomatic adults were screened for atopy via skin prick test over 10 years (2006–2016) in the Division of Respirology. An atopic screen was performed with twenty common aeroallergens by a single investigator, Dr. D. Cockcroft. A positive test was considered to be a wheal ≥3 mm and markedly positive reactions ≥8 mm were also documented.ResultsThe prevalence of atopy by means of a positive skin test (≥3 mm) was 45.5%. The prevalence of one or more markedly positive reactions (≥8 mm) was 29.5% of the total population. The most frequent sensitization was to cat dander (58.2%), followed by mixed grass (32.1%), and birch (26.8%). Dust mite sensitization was 22.4% and mouse 6.2%. A positive epidemiology screen for cat/grass/mite would have incorporated 82.0% (n = 373) of subjects with positive skin tests. Those who failed the cat/grass/mite screen were mainly sensitized to trees (n = 34), molds (n = 22), weeds (n = 7), and animals (n = 8).ConclusionsThere is a high prevalence of cat sensitization in Saskatchewan, much higher than recorded in other centers internationally. This is likely due to a high proportion of cat ownership. The prevalence of mite sensitization is lower than those mentioned at other centres likely due to Saskatchewan’s dry climate. The significance of the rate of markedly positive reactions (≥8 mm wheal) when compared to humid areas with higher burden of mite is unknown. There is a low prevalence of roach also likely due to the dry climate and mouse sensitization was low but still identified as a significant indoor allergen. A cat/grass/mite screen may be useful with a 82.0% sensitivity.