RESUMO
Studies about thymic B cells are scarce in the literature, but it was suggested that they can exert modulatory and regulatory functions on the immune system. Thymic B cells can play some role in regulating the most frequent allergic background worldwide, the atopy induced by the mite Dermatophagoides pteronyssinus (Der p). Here, we aimed to evaluate if the polyclonal IgG repertoire produced by Der p-atopic individuals can influence the homing and cytokine profile of human thymic B derived from non-atopic children aged less than seven days. With this purpose, we produced polyclonal IgG formulations and cultivated human thymocytes in their presence. We also assessed IgG subclasses and the direct interaction of IgG with thymic B cell membranes. Our results could demonstrate that Der p-atopic IgG could not reduce the expression of α4ß7 homing molecule as observed in response to the other IgG formulations and could reduce the frequency of IFN-γ- and IL-9-producing thymic B cells compared to the mock condition. Der p-atopic IgG could also induce thymic IL-10-producing B cells compared to control conditions. The IgG derived from Der p-atopic individuals failed to diminish the population of IL-13-producing thymic B cells, unlike the reduction observed with other IgG formulations when compared to the mock condition. All IgG formulations had similar levels of IgG subclasses and directly interacted with thymic B cell membranes. Finally, we performed experiments using peripheral non-atopic B cells where IgG effects were not observed. In conclusion, our observation demonstrates that IgG induced in allergic individuals can modulate non-atopic thymic B cells, potentially generating thymic B cells prone to allergy development, which seems to not occur in mature B cells.
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Hipersensibilidade Imediata , Hipersensibilidade , Animais , Criança , Humanos , Interleucina-10 , Dermatophagoides pteronyssinus , Interleucina-9 , Interferon gama/metabolismo , Imunoglobulina G , Fenótipo , Antígenos de Dermatophagoides , AlérgenosRESUMO
BACKGROUND: Allergen-specific immunotherapy (AIT) is the only clinical approach that can potentially cure some allergic diseases by inducing immunological tolerance. Dermatophagoides pteronyssinus is considered as the most important source of mite allergens worldwide, with high sensitization rates for the major allergens Der p 1, Der p 2 and Der p 23. The aim of this work is to generate a hypoallergenic hybrid molecule containing T-cell epitopes from these three major allergens. METHODS: The hybrid protein termed Der p 2231 containing T-cell epitopes was purified by affinity chromatography. The human IgE reactivity was verified by comparing those with the parental allergens. The hybrid was also characterized immunologically through an in vivo mice model. RESULTS: The hybrid rDer p 2231 stimulated in peripheral blood mononuclear cells (PBMCs) isolated from allergic patients with higher levels of IL- 2, IL-10, IL-15 and IFN-γ, as well as lower levels of IL-4, IL-5, IL-13, TNF-α and GM-CSF. The use of hybrid molecules as a therapeutic model in D. pteronyssinus allergic mice led to the reduction of IgE production and lower eosinophilic peroxidase activity in the airways. We found increased levels of IgG antibodies that blocked the IgE binding to the parental allergens in the serum of allergic patients. Furthermore, the stimulation of splenocytes from mice treated with rDer p 2231 induced higher levels of IL-10 and IFN-γ and decreased the secretion of IL-4 and IL-5, when compared with parental allergens and D. pteronyssinus extract. CONCLUSIONS: rDer p 2231 has the potential to be used in AIT in patients co-sensitized with D. pteronyssinus major allergens, once it was able to reduce IgE production, inducing allergen-specific blocking antibodies, restoring and balancing Th1/Th2 immune responses, and inducing regulatory T-cells.
Assuntos
Antígenos de Dermatophagoides , Epitopos de Linfócito T , Hipersensibilidade , Animais , Humanos , Camundongos , Alérgenos , Antígenos de Dermatophagoides/imunologia , Antígenos de Dermatophagoides/farmacologia , Antígenos de Dermatophagoides/uso terapêutico , Proteínas de Artrópodes , Dermatophagoides pteronyssinus , Epitopos de Linfócito T/química , Epitopos de Linfócito T/uso terapêutico , Hipersensibilidade/tratamento farmacológico , Imunoglobulina E , Interleucina-10 , Interleucina-4 , Interleucina-5 , Leucócitos Mononucleares , Pyroglyphidae , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Imunoterapia/métodosRESUMO
The outer-membrane-derived proteoliposome (PL) of Neisseria meningitidis has been reported as a potent vaccine adjuvant, inducing a Th1-skewed response. This work aimed to assess the immunogenicity of a novel anti-allergic vaccine candidate based on allergens from Dermatophagoides siboney house dust mite and a combination adjuvant containing PL and Alum. In a preventative experimental setting, BALB/c mice were administered with three doses containing 2⠵g of Der s1 and 0.4⠵g Der s2 allergen, PL and Alum, at 7 days intervals, by subcutaneous route. Furthermore, mice were subjected to an allergen aerosol challenge for 6 consecutive days. Serum IgE, IgG1, and IgG2a allergen-specific antibodies were assessed by ELISA. Cytokine levels in supernatants of D. siboney stimulated lymphocyte cultures and in bronchoalveolar lavage (BAL) were measured by ELISA. Lung tissues were subjected to histological examination. The vaccine prevented the development of both, systemic (IgE) and local allergic responses (featuring lower IL-4, and IL-5 levels in BAL) upon allergen exposure by the inhalant route. Histological examination showed also a diminished allergic inflammatory response in the lungs. After the allergen challenge, cytokine levels in stimulated lymphocyte cultures showed lower values of IL-13 and augmented IFN-γ and IL-10. The vaccine induced a mixed IgG2a/IgG1 antibody response; although only IgG2a was PL-dependent. Both, IgG1/IgE and IgG2a/IgE ratios, showed significantly greater values in vaccinated mice. The findings support a preventative anti-allergic effect associated with the induction of a Th1-like IFN-γ/IL-10 response. IgG1/IgE and IgG2a/IgE ratios could be useful biomarkers for translation into clinical trials.
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Blomia tropicalis and Dermatophagoides pteronyssinus play an important role in triggering allergy. Glycycometus malaysiensis causes IgE reaction in sensitive people, but is rarely reported in domestic dust, because it is morphologically similar to B. tropicalis making the identification of these species difficult. The identification of mites is mostly based on morphology, a time-consuming and ambiguous approach. Herein, we describe a multiplex polymerase chain reaction (mPCR) assay based on ribosomal DNA capable to identify mixed cultures of B. tropicalis, D. pteronyssinus and G. malaysiensis, and/or to identify these species from environmental dust. For this, the internal transcribed spacer 2 (ITS2) regions, flanked by partial sequences of the 5.8S and 28S genes, were PCR-amplified, cloned and sequenced. The sequences obtained were aligned with co-specific sequences available in the GenBank database for primer design and phylogenetic studies. Three pairs of primers were chosen to compose the mPCR assay, which was used to verify the frequency of different mites in house dust samples (n = 20) from homes of Salvador, Brazil. Blomia tropicalis was the most frequent, found in 95% of the samples, followed by G. malaysiensis (70%) and D. pteronyssinus (60%). Besides reporting for the first time the occurrence of G. malaysiensis in Brazil, our results confirm the good resolution of the ITS2 region for mite identification. Furthermore, the mPCR assay proved to be a fast and reliable tool for identifying these mites in mixed cultures and could be applied in future epidemiological studies, and for quality control of mite extract production for general use.
Assuntos
Dermatophagoides pteronyssinus , Ácaros , Animais , Antígenos de Dermatophagoides , Brasil , Poeira , Humanos , Reação em Cadeia da Polimerase Multiplex , FilogeniaRESUMO
Cryptococcosis (caused, for example, by Cryptococcus neoformans) and allergic asthma (caused, for example, by Dermatophagoides pteronyssinus) target the respiratory tract (the lung and bronchial epithelium). C. neoformans and D. pteronyssinus can coexist in the same indoor environment, and exposure to both can cause alterations in the local airway inflammatory milieu and exacerbation of airway inflammatory diseases. Here, we evaluated the effects of the association between C. neoformans and D. pteronyssinus in the modulation of airway inflammatory responses in an in vitro experimental model using human bronchial epithelial cells. BEAS-2B cells were cultivated and stimulated with D. pteronyssinus (10 µg/mL) and/or C. neoformans (MOI 100) for 24 h. No cytotoxic effect was observed in cells stimulated by C. neoformans and/or D. pteronyssinus. The production of IL-8, IL-6, and/or CCL2, but not IL-10, as well as the activation of NF-kB, STAT3, STAT6, and/or ERK1/2 were increased in cells stimulated by C. neoformans or D. pteronyssinus compared to controls. C. neoformans in association with D. pteronyssinus inhibited the CCL2ERK1/2 signaling pathway in cells treated with both pathogens compared to cells stimulated by D. pteronyssinus alone. In addition, their association induced an additive effect on the IL-6/STAT3 signaling pathway in cells compared to cells stimulated with D. pteronyssinus or C. neoformans only. D. pteronyssinus increased the internalization and growth of C. neoformans in BEAS-2B cells. D. pteronyssinus in association with C. neoformans promoted pro- and anti-inflammatory responses, which can modulate cryptococcal infection and asthmaticus status.
Assuntos
Criptococose , Cryptococcus neoformans , Animais , Anti-Inflamatórios/farmacologia , Brônquios , Quimiocina CCL2/metabolismo , Criptococose/metabolismo , Cryptococcus neoformans/metabolismo , Dermatophagoides pteronyssinus/metabolismo , Regulação para Baixo , Células Epiteliais/metabolismo , Humanos , Interleucina-6/metabolismo , Sistema de Sinalização das MAP Quinases , Fator de Transcrição STAT3/metabolismoRESUMO
BACKGROUND: Allergic diseases figure among the most common immune-mediated diseases worldwide, affecting more than 25% of the world's population. Allergic reactions can be triggered by house dust mite (HDM) allergens, of which the so-called group 21 of allergens is considered as clinically relevant. METHODS: Herein, we used a structural bioinformatics and immunoinformatics approach to design hypoallergenic mutant variants of the Der p 21 allergen of Dermatophagoides pteronyssinus, which were then recombinantly expressed in bacteria and tested for their IgE-reactivities. For this, we scanned the wild-type Der p 21 protein for all possible single amino acid substitutions in key IgE-binding regions that could render destabilization of the major epitope regions. RESULTS: Four main substitutions (D82P, K110G, E77G, and E87S) were selected to build mutant variants of the Der p 21 allergen, which were produced in their recombinant forms; two of these variants showed reduced reactivity with IgE. Molecular dynamic simulations and immune simulations demonstrated the overall effects of these mutations on the structural stability of the Der p 21 allergen and on the profile of immune response induced through immunotherapy. CONCLUSIONS: When produced in their recombinant forms, two of the Der p 21 mutant variants, namely proteins K110G and E87S, showed significantly reduced IgE reactivities against sera from HDM-allergic individuals (n = 20; p < 0.001). GENERAL SIGNIFICANCE: This study successfully translated a rational in silico mutagenesis design into low IgE-binding mutant variants of the allergen rDer p 21. These novel hypoallergens are promising to compose next-generation allergen-immunotherapy formulations in near future.
Assuntos
Hipersensibilidade , Imunoglobulina E , Alérgenos/genética , Animais , Antígenos de Dermatophagoides/química , Antígenos de Dermatophagoides/genética , Proteínas de Artrópodes/genética , Humanos , Hipersensibilidade/genética , Imunoglobulina E/genética , Pyroglyphidae/genética , Pyroglyphidae/metabolismoRESUMO
RESUMEN Fundamento: La inmunoterapia consiste en la administración de dosis crecientes del alérgeno para controlar la sensibilidad hacia este. Objetivo: Describir el comportamiento de la inmunoterapia por vía subcutánea o sublingual a ácaros. Metodología: Estudio retrospectivo realizado en Cabaiguán, periodo de 2010 a 2019, el universo de 267 pacientes con pruebas positivas a ácaros y la muestra de 53 pacientes. Los datos se obtuvieron del registro de datos. Resultados: Usó la vía sublingual el 60.4 %, predominó el grupo de edad entre 5-18 años (41.5 %), la vía subcutánea se utilizó en un 39.6 %, fue más frecuente en el sexo masculino (58.5 %). La vía subcutánea se indicó mayoritariamente en la rinitis alérgica (20.7 %) y la sublingual en el asma (32.1 %); para ambas, fue el Dermatofagoide pteronyssinus el ácaro de mayor sensibilidad y utilización (43.4 %), el tiempo de administración dominante fue de 3 años (67.9 %). El control de los síntomas se alcanzó con la vía sublingual (37.7 %). En la vía sublingual no se presentaron eventos adversos en el 43.3 %, con la vía subcutánea 11.3 % de los eventos adversos fueron locales y 7.6 % sistémicos leves. Conclusiones: La vía sublingual fue la más utilizada, la de mayor control de los síntomas y menos eventos adversos en el estudio.
ABSTRACT Background: Immunotherapy consists of the administration of the allergen increasing doses to control sensitivity towards it. Objective: To describe the behavior of subcutaneous or sublingual immunotherapy to mites. Methodology: Retrospective study carried out in Cabaiguán, from 2010 to 2019, the universe of 267 patients with positive tests to mites and the sample 53 patients. Data were obtained from the data record. Results: 60.4 % used sublingual, the age group between 5-18 years prevailed (41.5 %), the subcutaneous was used in 39.6 %, and it was more frequent in males (58.5 %). The subcutaneous was indicated mainly in allergic rhinitis (20.7 %) and sublingual in asthma (32.1 %); for both, Dermatofagoide pteronyssinus was the highest sensitivity and use mite (43.4 %) the dominant administration time was 3 years (67.9 %). Symptom control was achieved by sublingual (37.7 %). In sublingual, there were no adverse events in 43.3 %, with the subcutaneous, 11.3 % of the adverse events were local and 7.6 % were mild systemic. Conclusions: Sublingual was the most used, the one with the highest control of symptoms and the fewest adverse events in the study.
Assuntos
Testes Cutâneos , Antígenos de Dermatophagoides , Imunoterapia Sublingual , Injeções Subcutâneas , ÁcarosRESUMO
Canine demodicosis is a common inflammatory parasitic skin disease caused by Demodex mites. House dust mites, such as Dermatophagoides spp., play an important role in the pathogenesis of canine atopic dermatitis (AD). The goal of this experimental work was to investigate whether demodectic dogs could be previously exposed/sensitized to house dust mites' antigens. First the prevalence of demodicosis in a southeastern region of Brazil was investigated by analyzing clinical files of dogs that were admitted to a Veterinary Hospital. Subsequently, the IgG responses to Dermatophagoides pteronyssinus (Dp) and Dermatophagoides farinae (Df) and IgE to D.pteronyssinus (Dp) were evaluatedin two groups, AD or demodicosis dogs. Additionally, the major IgE-binding Dp proteins that are recognized by sera from dogs with demodicosis and AD were evaluated. A total of 2,599 clinical files were analyzed to identify the major parasitic skin diseases in dogs from this region, considering the age, sex and breed of the animals. The epidemiological study identified 111 animals with skin diseases; from these 20.7% presented demodicosis. Afterwards, serum samples were obtained from another groups of demodicosis, AD, and healthy dogs, and analyzed for Dp and Df-specific IgG, and IgE antibody levels, Dp IgG avidity by ELISA and IgE-binding Dp-specific proteins by immunoblot. IgG and IgE antibodies to Dp were detected in sera from additional groups of dogs with AD, demodicosis or healthy, with higher IgE levels to Dp in AD than demodectic or healthy dogs. IgG to Df was detected, despite with smaller levels compared to Dp in sera from demodectic dogs, and also in healthy dogs. Immunoblot showed IgE-binding to Dp proteins in sera of dogs with demodicosis and AD; with strong reactivity for the 72 and 116 kDa antigens detected by sera from demodicosis dogs. However, sera from healthy dogs >12 months old also presented reactivity to these bands. In conclusion, the detection of Dp-IgG and IgE antibodies in sera from demodectic dogs indicates previous exposure and sensitization to the house dust mite, respectively, more than cross-reactivity between demodex mites and Dp antigens detected by canine antibodies. Additionally, higher Dp-specific IgE levels were found in dogs with AD compared with those with demodicosis or healthy, suggesting that Dp-specific IgE could better discriminate dogs with AD from healthy ones or even those with demodicosis.
Demodicose canina é uma doença inflamatória comum da pele causada por ácaros do gênero Demodex. Ácaros da poeira doméstica como Dermatophagoides spp. desempenham papel importante na patogênese da dermatite atópica canina (DA). O objetivo desse trabalho experimental foi investigar se cães com demodicose poderiam ser previamente expostos/sensibilizados com antígenos de ácaros da poeira doméstica. A princípio, investigou-se a prevalência de demodicose em uma região sudeste do Brasil, analisando-se prontuários clínicos de cães admitidos em um Hospital Veterinário. Posteriormente, as respostas de IgG a Dermatophagoides pteronyssinus (Dp) e D. farinae (Df) e IgE a D. pteronyssinus (Dp) foram avaliadas em dois grupos, DA ou demodicose. Também foram avaliadas as principais proteínas Dp reconhecidas por anticorpo IgE presente em soros de cães com demodicose e DA. Um total de 2.599 prontuários clínicos foram analisados para identificar as principais doenças parasitárias da pele em cães dessa região, considerando a idade, sexo e raça dos animais. O estudo epidemiológico detectou 111 animais com doenças de pele e destes, 20,7% apresentavam demodicose. Posteriormente, amostras de soro foram obtidas de outros grupos de cães com demodicose, DA ou saudáveis, e analisadas quanto aos níveis de IgG e IgE específicos para Dp e Df, avidez de IgG a Dp por ELISA e proteínas específicas de Dp reconhecidas por IgE por immunoblot. Anticorpos IgG e IgE para Dp foram detectados em soros de grupos adicionais de cães com DA, demodicose ou saudáveis, com níveis mais altos de IgE para Dp na DA do que no soro de animais saudáveis. Níveis de IgG específicos para Df foram detectados, apesar serem menores em comparação com os detectados para Dp em soros de cães demodéticos, e também em cães saudáveis. A análise de immunoblot demonstrou detecção de IgE para proteinas de Dp em soros de cães com demodicose e DA; com forte reatividade para os antígenos de 72 e 116 kDa detectados por soros de cães com demodicose. No entanto, soros de cães saudáveis > 12 meses de idade também apresentaram reatividade a essas bandas. Em conclusão, a detecção de anticorpos Dp-IgG e IgE específicos em soros de cães demodéticos indica exposição prévia e sensibilização aos ácaros, respectivamente, mais do que reatividade cruzada entre ácaros Demodex e antígenos Dp detectados por anticorpos caninos. Além disso, níveis de Dp-IgE específicos mais elevados encontrados em cães com DA, sugerem que esses anticorpos poderiam discriminar melhor cães com DA daqueles saudáveis ou mesmo demodéticos.
Assuntos
Imunoglobulina E , Imunoglobulina G , Dermatophagoides pteronyssinus , CãesRESUMO
BACKGROUND: Sensitization to Blomia tropicalis (Bt) is very frequent in the tropics, and particularly in Cuba, being a significant cause of allergic asthma. Allergen immunotherapy (AIT) with Bt can be a therapeutic option, however, placebo-controlled clinical trials have not been reported. OBJECTIVE: To assess the therapeutic effect and safety of AIT for asthma using a standardized allergen vaccine of B. tropicalis by subcutaneous route, in allergic asthmatic patients exposed and sensitized to this mite species. METHODS: A double-blind, placebo-controlled Phase II trial was conducted in 35 adults (18 with treatment and 17 with placebo), with mild to moderate asthma, predominantly sensitized to Bt. AIT was administered subcutaneously in increasing doses from 4 to 6000 Biological Units using a locally manufactured standardized extract (BIOCEN, Cuba). Patient assessment was performed using symptom-medication score (SMS), peak expiratory flow and skin reactivity relative to Histamine as measured by skin prick test (SPT). RESULTS: The 12-month treatment achieved a significant (p < 0.001) decrease of SMS. Symptom score showed only 41% (CI: 26-61) of placebo values, whereas medication was 34.5% (22.4%-63.3%). Treatment was regarded clinically effective in 67% of patients (OR 32; 95%CI: 17 to 102). The effect size on symptoms and medication was higher than has been reported with equivalent allergen dosages of D. pteronyssinus and D. siboney in Cuban asthmatic patients. Skin reactivity to Bt was also significantly reduced (p = 0.0001), increasing 148-fold the allergen threshold to elicit a positive skin test. This desensitization effect was specific to Bt and did not modify the reactivity to Dermatophagoides. The change of specific skin reactivity was significantly (p < 0.05) correlated to clinical improvement. All adverse events were local with a frequency of 2.4% of injections. CONCLUSIONS: Subcutaneous AIT with Blomia tropicalis was effective and safe in asthmatic adults exposed and sensitized to this mite species in a tropical environment. TRIAL REGISTRATION: Cuban Public Registry of Clinical Trials: RPCEC00000026 (WHO International Clinical Trial Registry Platform ICTRP).
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BACKGROUND: The skin prick test is recognized as the gold standard for the specific diagnosis of allergy. OBJECTIVE: To determine the sensitivity and specificity of the epicutaneous patch test that has been modified for the diagnosis of respiratory allergy to Dermatophagoides pteronyssinus. METHODS: An observational, interpretative, prolective, and transversal study. The included patients were between 6 and 49 years old, with symptoms of a respiratory allergy, and a skin test was performed on them by using the European standardized prick test and a modified epicutaneous patch test with the variable of the scarification that occurred before the antigen was applied, and its homogenization with a wooden applicator, which occurred after the antigen was applied. The levels of sensitivity, specificity, and prevalence influence and positive and negative predictive values were calculated. RESULTS: 104 patients were included, of which 72 (69.2%) were women. The age category of the patients was 24 ± 11.3 years of age. 78.9% of the patients were diagnosed with allergic rhinitis, 1.9% were diagnosed with asthma, and 19.2% were diagnosed with both rhinitis and asthma. The prevalence of the respiratory allergy to Dermatophagoides pteronyssinus was of 62.5%; 94.23% with a correct diagnosis. The sensitivity and specificity of the test was of 93.85% and 94.87%; the positive and negative predictive values were of 96.83% and 90.24%, and the positive and negative likelihood ratios were of 18.30 and 0.06. CONCLUSIONS: The modified epicutaneous patch test was highly sensitive and specific; it decreased the risk of allergen carryover and it lowered the cost of the material that was used.
Antecedentes: La prueba por punción cutánea es el estándar de oro en el diagnóstico específico de alergia. Objetivo: Determinar sensibilidad y especificidad de la prueba epicutánea modificada para el diagnóstico de alergia respiratoria a Dermatophagoides pteronyssinus. Métodos: Estudio observacional, interpretativo, prolectivo y transversal. Se incluyeron pacientes de seis a 49 años de edad, con cuadro clínico de alergia respiratoria, en quienes se realizó punción cutánea con técnica europea y prueba epicutánea con la variante de escarificación previa a la aplicación del antígeno y posterior homogenización del mismo con aplicador de madera. Se calculó sensibilidad, especificidad, influencia de la prevalencia, valores predictivos positivo y negativo. Resultados: Se incluyeron 104 pacientes, 72 (69.2 %) del sexo femenino. La edad fue de 24 ± 11.3 años, 78.9 % tuvo diagnóstico de rinitis alérgica, 1.9 % de asma y 19.2 % de rinitis y asma. La prevalencia de alergia respiratoria a Dermatophagoides pteronyssinus fue de 62.5 %; 94.23 % estaba correctamente diagnosticado. La sensibilidad y especificidad de la prueba fue de 93.85 y 94.87 %, los valores predictivos positivo y negativo de 96.83 y 90.24 % y los cocientes de probabilidades positivo y negativo de 18.30 y 0.91. Conclusiones: La prueba epicutánea modificada fue altamente sensible y específica, disminuyó el riesgo de contaminación por arrastre de alérgenos y los costos en el material utilizado.
Assuntos
Asma/diagnóstico , Asma/imunologia , Dermatophagoides pteronyssinus/imunologia , Testes do Emplastro/métodos , Rinite Alérgica/diagnóstico , Rinite Alérgica/imunologia , Adolescente , Adulto , Animais , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto JovemRESUMO
BACKGROUND: The aim of this study was to evaluate the positivity rates of atopy patch tests for Dermatophagoides pteronyssinus, Dermatophagoides farinae and Blomia tropicalis in patients with respiratory diseases such as asthma and allergic rhinitis with or without atopic dermatitis. METHODS: The patients' clinical histories were collected, and the patients were subjected to skin prick and patch tests with the three different house dust mites on the same day. The patch tests were examined 48 hours later, and then patients were divided into two groups: I- patients with respiratory diseases, such as asthma and/or rhinitis, and atopic dermatitis and II-patients with only respiratory diseases. A total of 74 patients ranging in age from 2 to 60 years were included in this study; 16 patients were included in group I and 58 were included in group II. This study was approved by the human ethics committee of the Faculty of Medical Science and Health SUPREMA (number 2.007.135), and written informed consent was collected from each patient or their parents prior to enrollment. RESULTS: In the skin prick tests, the most prevalent mite that evoked a reaction was Dermatophagoides pteronyssinus, followed by Dermatophagoides farinae and Blomia tropicalis. Regarding the atopy patch tests, the mite that most frequently induced a positive reaction was Dermatophagoides farinae (78.4%), followed by Dermatophagoides pteronyssinus (77%) and Blomia tropicalis (52.7%). A comparison of the skin prick and atopy patch tests revealed that 53 patients (71.6%) were positive on both tests, and 30 (56.6%) patients were positivite for the same mite. We found six patients (8%) who had a positive clinical history of allergy and only exhibited positivity on the atopy patch test. DISCUSSION: Most studies have been performed with atopic dermatitis patients, but in this study, most of the patients had respiratory conditions. Blomia tropicalis is a mite that is prevalent in tropical areas, such as Brazil, and only two publications include these three mites, wich are present in Brazil. The APT may produce positive results in concordance with the SPT resuts, but may also be the only positive test ( 8%) as we observed in our study. These results suggest that the mite atopy patch test is relevant and should be considered as an additional test for patients with clinical histories of allergic respiratory disease who have negative prick test results. CONCLUSION: The APT should be considered as an additional test when the SPT and specific serum IgE tests are negative in patients with clinical histories of allergies.
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BACKGROUND: High-dose aqueous subcutaneous immunotherapy is a validated and effective administration route for house dust mite and pollen allergens. OBJECTIVE: A proof-of-concept study using intradermal immunotherapy (IDIT) with low-dose house dust mite allergens (Dermatophagoides pteronyssinnus/Dermatophagoides farinae [Dp/Df] and Blomia tropicalis [Bt]) was carried out in children with allergic rhinitis symptomatic upon exposure to house dust. METHODS: Eight immunotherapy-naïve patients with positive prick skin tests and specific serum IgE to a Dp/Df mixture and to Bt were weekly administered 0.05 mL of an IDIT consisting of a phenolyzed albumin-saline preparation containing low-dose dust mites (8.3 AU [5 ng] of Dp/Df and 2.5 DBU of Bt), for 3 months. Nasal (Total Nasal Symptom Score) and facial symptoms (Visual Analog Scale) were recorded 2 weeks prior to treatment and once weekly during its course. Serial dilutions skin prick tests (1/100-1/1.000.000) and serum allergen-specific IgG4 determinations were performed at baseline and at treatment conclusion. RESULTS: Values on the scales suggested clinical improvement. There was a significant decrease in serial dilutions skin prick tests' wheal diameters, as well as an increase in serum IgG4 values at treatment completion. IDIT was well tolerated. CONCLUSION: If the present results are confirmed by further studies, allergen-specific immunotherapy wider use could be promoted.
Antecedentes: La inmunoterapia subcutánea acuosa a altas dosis es una ruta validada y efectiva de administración de alérgenos para el ácaro del polvo doméstico y alergias al polen. Objetivos: Estudio de definición conceptual empleando inmunoterapia intradérmica (ITID) con alérgenos de ácaros (Dermatophagoides pteronyssinus/Dermatophagoides farinae [Dp/Df] y Blomia tropicalis [Bt]) a bajas dosis; se llevó a cabo en niños con rinitis alérgica sintomáticos a la exposición de polvo de casa. Métodos: A ocho pacientes sin uso previo de inmunoterapia, con pruebas de punción cutánea positivas e IgE sérica específica a una mezcla de Dp/Df y Bt, se les administraron por tres meses 0.05 mL de ITID semanalmente, provenientes de una preparación fenolizada albúmino-salina y contentiva de bajas dosis de ácaros (8.3 AU= 5 ng de Dp/Df y 2.5 DBU de Bt). Los síntomas nasales (Total Nasal Symptom Score) y los faciales (Escala Análoga Visual) fueron registrados dos semanas antes del tratamiento y en el transcurso una vez a la semana. Al comienzo y al final se realizaron pruebas cutáneas diluidas y seriadas (1/100-1/1.000.000) y determinaciones de IgG4 en el suero para los alérgenos. Resultados: Los valores de las escalas sugirieron mejoría clínica. Existió disminución significativa de los diámetros de las pápulas de las pruebas diluidas y seriadas, así como aumento de los valores de la IgG4 sérica al final del tratamiento. La ITID fue bien tolerada. Conclusión: Si estudios ulteriores confirman los presentes hallazgos, se podría promover una mayor utilización de la inmunoterapia alérgeno-específica.
Assuntos
Alérgenos/administração & dosagem , Dessensibilização Imunológica/métodos , Pyroglyphidae/imunologia , Rinite Alérgica/terapia , Adolescente , Animais , Criança , Feminino , Humanos , Injeções Intradérmicas , Masculino , Projetos Piloto , Estudo de Prova de ConceitoRESUMO
The proteoliposome (PL) of Neisseria meningitidis serogroup B has been reported as a safe and potent vaccine adjuvant, inducing a TH1-skewed response. The present study describes a pre-clinical safety evaluation of an allergy therapeutic vaccine candidate based on purified allergens from Dermatophagoides siboney house dust mite and PL as adjuvant, both components adsorbed onto aluminum hydroxide gel. Two separate studies of acute toxicity evaluation were performed in mice and rabbits, and two repeat-dose studies were conducted in non-sensitized and allergen-sensitized Balb/c mice, respectively. The study in sensitized mice intends to model a therapeutic setting. Aerosolized allergen challenge was used in both settings to model natural respiratory exposure. In the therapeutic setting, mice were administered with three doses containing 2 µg allergen at weekly intervals [subcutaneous route] and subsequently challenged with aerosolized allergen for 6 consecutive days. Parameters of general toxicity effects were assessed via measures of behavior, body weight, food and water consumption, and macroscopic evaluation of organs. Histological examination of organs and the injection site was performed. Potential immunotoxicity effects at the systemic level were assessed by blood eosinophil counting and serum allergen specific IgE by ELISA The vaccine did not produce general or functional toxic effects of significance, at a dose up to 100 µg allergen per kg body weight. An expected local reaction at the injection site was observed, which could be attributed mostly to the immunological effect of aluminum hydroxide. The models implemented here suggest an acceptable safety profile of this vaccine for testing in clinical trials of allergy immunotherapy.
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Antígenos de Dermatophagoides/imunologia , Dessensibilização Imunológica/métodos , Hipersensibilidade/terapia , Neisseria meningitidis/metabolismo , Proteolipídeos/administração & dosagem , Vacinas/imunologia , Adjuvantes Imunológicos/efeitos adversos , Hidróxido de Alumínio/administração & dosagem , Animais , Eosinófilos/imunologia , Hipersensibilidade/imunologia , Imunoglobulina E/sangue , Camundongos , Proteolipídeos/efeitos adversos , Proteolipídeos/metabolismo , Pyroglyphidae , CoelhosRESUMO
Bronchial epithelial cells are essential to airways homeostasis; however, they are also involved in exacerbation of airway inflammatory responses of patients with conditions such as asthma. Dermatophagoides pteronyssinus (Dp), the most important allergen, and lipopolysaccharide (LPS), both of which are present in house dust mites (HDM), can activate immune and structural cells (such as bronchial epithelial cells) and modulate the airway inflammation in asthma patients. Resolvin D1 (RvD1) and its epimer aspirin-triggered-resolvin D1 (AT-RvD1) are lipid mediators that are produced during the resolution of inflammation and demonstrate anti-inflammatory and pro-resolution effects in several experimental models including experimental models of allergic airway inflammation. Here, we evaluated the effects of AT-RvD1 (10-12-10-10 M) on human bronchial epithelial cells (BEAS-2B) stimulated with LPS (2µg/ml) or Dp (10µg/ml). After 24h, the C-C motif chemokine ligand 2 (CCL-2) production was increased in cells that had been stimulated with LPS and Dp compared to the control. However, AT-RvD1 (10-11 and 10-10 M) significantly reduced the concentration of CCL-2 in a manner that was dependent on the N-formyl peptide receptor 2 (FPR2/ALX) and nuclear factor kappa B (NF-κB) pathways in cells stimulated with LPS or Dp compared to controls. In addition, AT-RvD1 reduced the phosphorylation of signal transducer and activator of transcription (STAT)6 and STAT1 in cells stimulated with Dp and LPS, respectively. In conclusion, AT-RvD1 demonstrated significant anti-inflammatory effects in bronchial epithelial cells that were stimulated with LPS or Dp, which provides new perspectives for therapeutic strategies to control inflammatory airway diseases.
Assuntos
Aspirina/farmacologia , Brônquios/citologia , Dermatophagoides pteronyssinus/fisiologia , Ácidos Docosa-Hexaenoicos/farmacologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Animais , Aspirina/química , Linhagem Celular , Relação Dose-Resposta a Droga , Humanos , EstereoisomerismoRESUMO
BACKGROUND: In spite of allergen-specific immunotherapy (SIT) multiple benefits, its use is restricted in some countries owing to concerns about severe adverse reactions. OBJECTIVE: To evaluate systemic adverse reactions in patients with atopic dermatitis, allergic asthma, allergic rhinitis and allergic conjunctivitis who received subcutaneous immunotherapy with tyrosine-adsorbed Dermatophagoides and Glycyphagoides dust mites extracts. METHODS: Retrospective study of the 2010-2015-period that included 773 patients diagnosed with IgE-mediated diseases, where the safety of allergen-specific immunotherapy was described according to the World Organization of Allergy subcutaneous immunotherapy-induced systemic reactions classification system. RESULTS: 79.7 % of patients had rhinitis, 54.9 % asthma, 34.5 % conjunctivitis and 16.4 % atopic dermatitis. Out of 12,546 tyrosine-adsorbed extract doses, 45 systemic reactions were recorded: 12 were grade 1 (30 %), 27 grade 2 (67.5 %) and 1 was grade 3 (2.5 %); the reaction rate was 0.35 per 100 administered injections, for an incidence rate of 5.8 %. No fatal reactions occurred. CONCLUSION: The frequency of systemic reactions with subcutaneous immunotherapy with Dermatophagoides farinae, Dermatophagoides pteronyssinus and Blomia tropicalis tyrosine-adsorbed extracts was similar to that reported with other extracts.
Antecedentes: Pese a los múltiples beneficios de la inmunoterapia alérgeno-específica, en algunos países se restringe su uso por temor a las reacciones adversas severas. Objetivo: Evaluar las reacciones sistémicas adversas en pacientes con dermatitis atópica, asma, rinitis y conjuntivitis alérgicas, que recibieron inmunoterapia subcutánea con extractos tirosinados para ácaros Dermatophagoides y Glycyphagoides. Métodos: Estudio retrospectivo del periodo 2010-2015 en el que se incluyó a 773 pacientes con diagnóstico de enfermedades mediadas por IgE. Se describió la seguridad de la inmunoterapia alérgeno-específica conforme al sistema de clasificación de las reacciones sistémicas con inmunoterapias subcutánea de la Organización Mundial de Alergias. Resultados: 79.7 % de los pacientes presentó rinitis, 54.9 % asma, 34.5 % conjuntivitis y 16.4 % dermatitis atópica. De 12 546 dosis subcutánea con extractos tirosinados se registraron 45 reacciones sistémicas: 12 grado 1 (30 %), 27 de grado 2 (67.5 %) y 1 grado 3 (2.5 %); la tasa de reacción fue de 0.35 por cada 100 inyecciones administradas, que representó una incidencia de 5.8 %. No se registraron reacciones fatales. Conclusión: Con la inmunoterapia subcutánea con extractos tirosinados de Dermatophagoides farinae, Dermatophagoides pteronyssinus y Blomia tropicalis se presentó una frecuencia de reacciones sistémicas similar a la informada con otros extractos.
Assuntos
Antígenos de Dermatophagoides/efeitos adversos , Dessensibilização Imunológica/efeitos adversos , Adolescente , Adsorção , Animais , Antígenos de Dermatophagoides/administração & dosagem , Antígenos de Dermatophagoides/química , Antígenos de Dermatophagoides/uso terapêutico , Asma/terapia , Criança , Pré-Escolar , Conjuntivite Alérgica/terapia , Dermatite Atópica/terapia , Dermatophagoides pteronyssinus/imunologia , Relação Dose-Resposta Imunológica , Feminino , Humanos , Masculino , Estudos Retrospectivos , Rinite/terapia , TirosinaRESUMO
BACKGROUND: House dust mites are a ubiquitous air allergen in the human habitat. It has been shown that exposure to them is a fundamental factor in sensitisation and development of atopic disease. The objective of the study was to analyse changes in sensitisation to Dermatophagoides pteronyssinus (Der p.) in children treated in a tertiary level care hospital in Mexico City for a period of 11 years and compare with other studies carried out in Mexico. METHODS: A retrospective study was performed at the Hospital Infantil de México Federico Gómez (HIMFG). Information was gathered from skin tests for Der p. performed in the Allergy Laboratory from January 2004 to April 2015. Patients 2-18 years old who presented for examination of some type of allergic condition and who had immediate hypersensitivity tests to Der p. were included in the study. Results were compared with prior reports from other institutions. Descriptive analysis and χ2 statistics were used. RESULTS: A total of 8794 patients were included in the study; 49.3% of the tests (95% CI 48-50) were positive for Der p. The percentage of monosensitised to mites was 2.7% for Der p. (95% CI 2-3). A significant difference was found between the results of older patients and those <6 years old. The frequency of sensitisation had a tendency to decrease during the 11 years analysed in all age groups. CONCLUSIONS AND CLINICAL RELEVANCE: The frequency of sensitisation to Der p. increased with age until reaching adolescence. In the last 11 years a decrease in sensitisation to this air allergen was observed.
Assuntos
Antígenos de Dermatophagoides/imunologia , Dermatophagoides pteronyssinus/imunologia , Hipersensibilidade/epidemiologia , Adolescente , Animais , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Hipersensibilidade/imunologia , Imunização , Masculino , México , Estudos Retrospectivos , Centros de Atenção Terciária , Fatores de TempoRESUMO
BACKGROUND: Asthma is a common chronic disease worldwide and Ascaris lumbricoides infection (ascariasis) is frequent in tropical regions. However, the effect of ascariasis on asthma severity has not been sufficiently explored. We sought to evaluate the influence of the IgE immune response to Ascaris extract and purified house dust mites (HDM) and Ascaris allergens on indicators of asthma severity in patients living in the tropics. METHODS: Asthmatic patients from Cartagena, Colombia were recruited. Clinical assessment included questionnaires, physical examination, allergy skin tests, spirometry, parasite stool examination and IgE antibody measurements. Asthma was diagnosed by a physician according to validated criteria. Indicators of severity were occurrence of severe dyspnea episodes, night awakenings events, > 4 emergency room (ER) visits and hospitalizations during the last year. Specific IgE to Der p 2, Ascaris spp., Blomia tropicalis and Dermatophagoides pteronyssinus extracts was determined by ImmunoCap. IgE to tropomyosins (Asc l 3, Blo t 10 and Der p 10), Blo t 5 and Asc s 1 was detected by ELISA. Logistic regression analyses were used to explore the relationships between sensitization and indicators of asthma severity. RESULTS: After adjustment for HDM sensitization, Ascaris sensitization remained associated with severe dyspnea (aOR: 1.90, 95% CI: 1.08 - 3.34, p = 0.03) and > 4 ER visits (aOR: 2.23, 95% CI: 1.15 - 4.30, p = 0.02). We also found that sensitization to the species specific markers Blo t 5 and Asc s 1, as well as the cross-reactive tropomyosins of D. pteronyssinus and Ascaris were associated with > 4 ER visits. Der p 2 sensitization was associated with bronchodilator responsiveness (aOR: 2.24: 1.25-4.02, p = 0.01). Remarkably, significantly higher IgE levels to HDM species specific allergens were found in Ascaris sensitized patients. CONCLUSIONS: In this tropical population, IgE sensitization to Ascaris and the cross-reactive tropomyosins was frequent and associated with clinical indicators of asthma severity. The significant relationship between sensitization to the nematode-specific marker Asc s 1 and ER attendance supports these findings. Moreover, ascariasis increases the human IgE responses to HDM specific allergens.
RESUMO
Introdução: Asma e rinite alérgicas são doenças inflamatórias crônicas das vias aéreas cuja principal etiopatogenia é a reação de hipersensibilidade ao ácaro da poeira. O único tratamento específico que modifica a história natural da doença é a imunoterapia alérgeno-específica (ITAE). Porém, as reações adversas ainda são uma dificuldade na consolidação da ITAE como forma de tratamento. Um meio de minimizar as reações e maximizar os efeitos terapêuticos é o uso de adjuvantes, entre eles vacinas e lipopolissacárides bacterianos, que objetivam aumentar o desvio da resposta imune de perfil T-helper (TH) 2 para TH1. A vacina de Bordetella pertussis de célula inteira (Pw) mostrou ter um papel protetor em modelos experimentais de asma induzida por ovalbumina. Porém, seu papel na alergia respiratória induzida por ácaros ainda não é conhecido. Nosso objetivo foi avaliar os efeitos da vacina tríplice bacteriana (difteria-tétano-coqueluche - DTPw) em um modelo murino de alergia respiratória crônica induzida pelo ácaro Dermatophagoides pteronyssinus (Derp). Métodos: O protocolo teve duração de 30 dias. Camundongos BALB/c foram divididos em 6 grupos, os quais foram sensibilizados por via subcutânea com solução salina ou Derp 50mcg, em três injeções. Três grupos foram imunizados com Derp, apenas com o ácaro ou associado as vacinas de difteria-tétano (DT) e DTPw, respectivamente. Os outros três receberam soro fisiológico, com ou sem vacinas DT e DTPw. Os animais, posteriormente, sofreram desafio intranasal com soro fisiológico ou Derp por 7 dias e foram sacrificados 24 horas após o último desafio. Medimos IgE, IgG1 e IgG2a séricas específicas anti-Derp; resistência, elastância e hiperresponsividade das vias aéreas; densidade de leucócitos polimorfonucleares (PMN) e área de muco ácido no epitélio nasal; celularidade no lavado bronco-alveolar (BAL); e remodelamento das vias aéreas inferiores. Resultados: Os animais sensibilizados com Derp produziram altos níveis de...
Background: Asthma and allergic rhinitis are chronic inflammatory diseases of the airways whose primary etiology is hypersensitivity reaction to house dust mite (HDM). The only specific treatment which modifies the natural history of the disease is the allergen specific immunotherapy (ASIT). However, adverse reactions are still a difficulty in consolidating ASIT as a good treatment option. One way to minimize adverse reactions and maximize therapeutic effects is the use of adjuvants, including bacterial lipopolysaccharide and vaccines that aim to shift immune response profile from T helper (TH) 2 to TH1. Bordetella pertussis whole-cell vaccine (Pw) has shown to have a protective role in experimental models of ovalbumin-induced asthma. Nevertheless, its role in respiratory allergy induced by HDM is unknown. Our objective was to evaluate the effects of diphtheria-tetanus-pertussis (DTPw) vaccine in a murine model of respiratory allergy induced by the HDM Dermatophagoides pteronyssinus (Derp). Methods: The protocol lasted 30 days. BALB/c mice were divided into 6 groups, which were sensitized subcutaneously (s.c.) with saline solution or Derp 50mcg, in three injections. Three groups were submitted to Derp alone or associated with diphtheria-tetanus (DT) vaccine and DTPw, respectively. The other three received saline solution with or without DT and DTPw vaccines. Subsequently mice underwent intranasal challenge with saline or Derp for 7 days and were sacrificed 24h after the last challenge. We measured serum specific IgE, IgG1 and IgG2a anti-Derp, airway resistance, elastance and hyperresponsiveness, density of polymorphonuclear (PMN) leukocytes infiltration in nasal mucosa, acidic nasal mucus content, cellularity in bronchoalveolar lavage (BAL) and lower airways remodeling. Results: HDM sensitized mice produced high levels of specific immunoglobulins, increased density of PMN leukocytes and acidic mucus in nasal mucosa, inflammatory cells in BAL due to...
Assuntos
Animais , Masculino , Adulto , Camundongos , Remodelação das Vias Aéreas , Asma , Dermatophagoides pteronyssinus , Imunoglobulina E , Inflamação , Modelos AnimaisRESUMO
Dermotophagoides farinae lives in the indoor environment of houses, where it is source of allergens; therefore its control is a priority in preventing respiratory allergies. The aim of this study was to evaluate the acaricidal activity of essential oil of Croton malambo H. Karst bark and their components methyl-eugenol and methyl-isoeugenol against Dermatophagoides farinae. The essential oil was obtained through hydro-distillation assisted by microwave radiation and analyzed by GC-MS. Acaricidal activity was assessed by dose- response bioassay, at different times, using benzyl benzoate as a positive control. The relative amount of methyl-eugenol and methyl- isoeugenol in the essential oil was 68.4 percent and 4.9 percent, respectively. The acaricidal activity was: essential oil > methyl-eugenol > benzyl benzoate > methyl-isoeugenol. The acaricidal properties of essential oil of Croton malambo bark and methyl-eugenol against Dermatophagoides farinae were established...
Dermatophagoides farinae habita en el interior de las casas, donde es fuente importante de alérgenos, por tanto su control es una prioridad en la prevención de alergias respiratoria. El objetivo de este estudio fue evaluar la actividad acaricida del aceite esencial de la corteza de Croton malambo H. Karst y sus componentes metil-eugenol y metil-isoeugenol contra Dermatophagoides farinae. El aceite esencial se obtuvo por hidrodestilación asistida por radiación de microondas y se analizó por CG-EM. La actividad acaricida se evaluó mediante bioensayo de dosis-respuesta a diferentes tiempos, usando benzoato de bencilo como control. La cantidad relativa de metil-eugenol y metil-isoeugenol en el aceite fue 68.4 por ciento y 4.9 por ciento, respectivamente. La actividad acaricida fue: aceite esencial > metil-eugenol > benzoato de bencilo > metil-isoeugenol. Se establecieron las propiedades acaricidas del aceite esencial de la corteza de Croton malambo y metil-eugenol contra Dermatophagoides farinae...