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BACKGROUND AND OBJECTIVE: Sensitization to Blomia tropicalis is associated with asthma in various tropical and subtropical countries; however, information about the specific molecular components associated with this disease is scarce. Using molecular diagnosis, we sought to identify B tropicalis allergens associated with asthma in Colombia. METHODS: Specific IgE (sIgE) to 8 B tropicalis recombinant allergens (Blo t 2, 5, 7, 8, 10, 12, 13, and 21) was determined using an in-house ELISA system in asthma patients (n=272) and controls (n=298) recruited in a national prevalence study performed in several Colombian cities (Barranquilla, Bogotá, Medellín, Cali, and San Andrés). The study sample included children and adults (mean [SD] age, 28 [17] years). Cross-reactivity between Blo t 5 and Blo t 21 was evaluated using ELISA-inhibition. RESULTS: Specific IgE (sIgE) to 8 B tropicalis recombinant allergens (Blo t 2, 5, 7, 8, 10, 12, 13, and 21) was determined using an in-house ELISA system in asthma patients (n=272) and controls (n=298) recruited in a national prevalence study performed in several Colombian cities (Barranquilla, Bogotá, Medellín, Cali, and San Andrés). The study sample included children and adults (mean [SD] age, 28 [17] years). Cross-reactivity between Blo t 5 and Blo t 21 was evaluated using ELISA-inhibition. CONCLUSION: Although Blo t 5 and Blo t 21 are considered common sensitizers, this is the first report of their association with asthma. Both components should be included in molecular panels for diagnosis of allergy in the tropics.
Assuntos
Alérgenos , Asma , Imunoglobulina E , Humanos , Asma/imunologia , Asma/diagnóstico , Asma/epidemiologia , Imunoglobulina E/imunologia , Imunoglobulina E/sangue , Adulto , Masculino , Feminino , Estudos de Casos e Controles , Criança , Adolescente , Colômbia/epidemiologia , Alérgenos/imunologia , Adulto Jovem , Pessoa de Meia-Idade , Antígenos de Plantas/imunologia , Reações Cruzadas , Clima Tropical , Prevalência , Pré-EscolarRESUMO
OBJECTIVE: To evaluate the IgE reactivity of sera in patients suffering from type 1 diabetes (T1D), lupus nephritis (LN) and juvenile idiopathic arthritis (JIA) against a molecule constructed from T epitopes of A. lumbricoides allergens. METHODS: We designed and expressed a synthetic multi-epítope protein named MP1 from A. lumbricoides and house dust mites allergens. By indirect ELISA, we evaluated IgE-reactivity to MP1 and to the whole-body extract of Ascaris lumbricoides in 45 sera from Colombian Caribbean patients with lupus nephritis (LN; n=25), type 1 diabetes (T1D; n=10) and Juvenil idiopathic arthritis (JIA; n=10). Individuals with poly autoimmunity were excluded. All patients were referred to the study by their specialist doctor. RESULTS: IgE to whole-body extract of A. lumbricoides showed the following median concentrations.484.2 ng/ml (IQR: 203.4) in JIA patients, 325.6 ng/ml (IQR: 179.3) in individuals with LN, and 424.7 ng/ml (IQR: 80.1) in the T1D group. On the other hand, IgE-reactivity to MP1 was 126.4 ng/ml (IQR: 90.9) in JIA patients, 130.7 ng/ml (IQR: 94.8) in an individual with LN, and 148.8 ng/ml (IQR: 102.1) in the T1D group. Although no statistical differences were observed between patient groups, the IgE to MP1 in all patients (n: 45) (IgE median: 134.2 ng/ml; IQR: 100) were significantly less compared to Ascaris extract (IgE median: 380.7 ng/ml; IQR: 175.8); (W: 0.732; p-value: 1.034x10-7). CONCLUSIONS: These preliminary results suggest that MP1 showed antigenic properties with low IgE- reactivity, compared to Ascaris lumbricoides extracted in individuals with autoimmune diseases. Further studies are needed to understand better the immune response induced by this molecule.
OBJETIVO: Evaluar la reactividad IgE de sueros en pacientes que padecen diabetes tipo 1 (DT1), nefritis lúpica (NL) y artritis idiopática juvenil (AIJ) frente a una molécula construida a partir de epítopes T de alérgenos de A. lumbricoides. MÉTODOS: Se diseñó y expresó una proteína multi-epítopes sintética (MP1), a partir de alérgenos de A. lumbricoides y ácaros del polvo doméstico. Mediante ELISA indirecto, se evaluaron las reactividades IgE anti-MP1 y al extracto de cuerpo entero de Ascaris lumbricoides, en sueros de pacientes con nefritis lúpica (NL; n=25), diabetes tipo 1 (T1D; n=10) y artritis idiopática juvenil (AIJ; n=10), procedentes del Caribe colombiano. Se excluyeron los individuos con poliautoinmunidad. Todos los pacientes fueron remitidos al estudio por su médico especialista. RESULTADOS: La IgE frente al extracto de cuerpo completo de A. lumbricoides mostró concentraciones de 484,2 ng/ml (RIQ: 203,4) en pacientes con AIJ; 325,6 ng/ml (RIQ: 179,3) en individuos con NL; y 424,7 ng/ml (RIQ: 80,1) en el grupo con DT1. Por otra parte, la reactividad de IgE anti-MP1 fue de 126,4 ng/ml (RIQ: 90,9) en los pacientes con AIJ; 130,7 ng/ml (RIQ: 94,8) en los individuos con NL; y 148,8 ng/ml (RIQ: 102,1) en el grupo con DT1. Aunque no se observaron diferencias estadísticas entre los grupos de pacientes, la reactividad IgE anti- MP1 en todos los pacientes (n: 45) (mediana de IgE: 134,2 ng/ml; RIQ: 100), fue significativamente inferior en comparación con el extracto de Ascaris (mediana de IgE: 380,7 ng/ml; RIQ: 175,8); (W: 0,732; p-valor: 1,034x10-7). CONCLUSIONES: Estos resultados preliminares sugieren que MP1 mostró propiedades antigénicas con baja reactividad IgE, en comparación con el extracto de Ascaris lumbricoides en individuos con enfermedades autoinmunes. Se necesitan más estudios para comprender mejor la respuesta inmunitaria inducida por esta molécula.
Assuntos
Alérgenos , Ascaris lumbricoides , Imunoglobulina E , Humanos , Animais , Ascaris lumbricoides/imunologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Alérgenos/imunologia , Feminino , Masculino , Doenças Autoimunes/imunologia , Doenças Autoimunes/sangue , Adolescente , Criança , Epitopos de Linfócito T/imunologia , AdultoRESUMO
OBJECTIVE: The objective of the present study was to design a multi-epitope protein from A. lumbricoides and APD allergens and to evaluate its IgE reactivity preliminarily. METHODS: Using computational tools, a molecule containing multiple "T" epitopes of allergens derived from A. lumbricoides and APD was designed "in silico" This multi-epitope protein (MP1) was expressed using an E. coli system and purified by affinity chromatography using Ni-NTA agarose. Anti-MP1 and anti-HDM extract IgE reactivity was evaluated by Dot-Blot and indirect ELISA from sera of HDM-allergic patients and non-allergic individuals from Barranquilla-Colombia. Allergic individuals had a positive skin test to a standardized battery of inhaled allergens (EUROLINE - Ref: DP 3704-1601-1 E) and mite- specific IgE. RESULTS: Multi-epitope (MP1) protein was expressed and purified with high purity. Dot-Blot result showed that all sera from allergic patients showed lower IgE reactivity to MP1 compared to HDM extract. By ELISA, significantly lower concentrations of anti-MP1 IgE (Median: 270.86 ng/ml; IQR: 90.3) were observed in contrast to anti-HDM IgE levels (Median: 988.5 ng/ml; IQR: 1117.6) in sera of patients allergic to HDM. CONCLUSIONS: A protein composed of multiple epitopes of A. lumbricoides and HDM allergens was designed, expressed, and purified. Preliminary Dot-Blot results suggest that this molecule shows hypoallergenic properties with very low IgE reactivity compared to mite extract. Further functional studies are needed to understand better the immune response induced by this molecule.
OBJETIVO: Diseñar una proteína multiepítope a partir de alérgenos de A. lumbricoides y APD; y evaluar preliminarmente su reactividad IgE. MÉTODOS: Mediante herramientas computacionales se diseñó In Silico, una molécula que contiene múltiples epítopos T, de alérgenos derivados de A. lumbricoides y APD. Esta proteína multiepítope (MP1) se expresó utilizando un sistema de E. coli, y se purificó mediante cromatografía de afinidad, empleando agarosa Ni-NTA. La reactividad IgE anti-MP1 y anti-extracto de APD, se evaluó mediante Dot-Blot y ELISA indirecta, a partir de suero de pacientes alérgicos a APD, e individuos no alérgicos procedentes de Barranquilla, Colombia. Los individuos alérgicos contaron con prueba cutánea positiva a una batería estandarizada de alérgenos inhalados (EUROLINE - Ref: DP 3704-1601-1 E) e IgE específica para ácaros. RESULTADOS: La proteína multiepítope MP1 se expresó y purificó con alta pureza. El resultado del Dot-Blot, mostró que todos los sueros de pacientes alérgicos tuvieron una reactividad IgE menor a MP1 en comparación al extracto de APD. Por ELISA, se observaron concentraciones significativamente menores de IgE anti-MP1 (Mediana: 270,86 ng/ml; RIQ: 90,3), en contraste a los niveles de IgE anti-APD (Mediana: 988,5 ng/ml; RIQ: 1117,6), en suero de pacientes alérgicos a APD. CONCLUSIONES: Se diseñó, expresó y purificó una proteína compuesta por múltiples epítopes de alérgenos de A. lumbricoides y APD. Los resultados preliminares de Dot-Blot sugieren que esta molécula muestra propiedad hipoalergénica con una reactividad IgE muy baja, en comparación con el extracto de ácaros. Se necesita continuar con estudios funcionales para comprender mejor la respuesta inmune inducida por esta molécula.
Assuntos
Alérgenos , Epitopos , Imunoglobulina E , Proteínas Recombinantes , Humanos , Imunoglobulina E/imunologia , Imunoglobulina E/sangue , Alérgenos/imunologia , Epitopos/imunologia , Proteínas Recombinantes/imunologia , Feminino , Masculino , Animais , Adulto , Clima Tropical , Adulto Jovem , Adolescente , Hipersensibilidade/imunologia , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To evaluate the risk of IgE sensitization and symptoms to shrimp in a population that has received AIT with polymerized mite extract. METHODS: Patients with allergic rhinitis sensitized to dust mites (Dermatophogides spp) with an indication for mite AIT were included. Those patients who had not yet received AIT or had received less than 6 doses were included as controls and those who had received more than 24 doses of AIT were included as cases. Sensitization to shrimp was assessed by skin prick test with complete shrimp extract and/or shrimp-specific IgE. RESULTS: A total of 68 patients were included; 47 cases and 21 controls. When calculating the odds ratio of sensitization according to time with immunotherapy we observed that there were no differences between the group of cases and controls (OR 0.76 95% CI 0.26 to 2.22 p 0.7 by MacNemar technique). Factors such as consumption or not of shrimp and frequency of consumption do not seem to be related to the outcome. CONCLUSION: In contrast to what was reported with aqueous extracts, we observed that AIT with polymerized extracts is not a risk factor for shrimp sensitization. It is necessary to reproduce these results with a larger sample size to explore other factors.
OBJETIVO: Evaluar el riesgo de sensibilización IgE y síntomas a camarón en una población que ha recibido AIT con extracto polimerizado para ácaros. MÉTODOS: Se incluyeron pacientes con rinitis alérgica sensibilizados a ácaros del polvo (Dermatophogides spp) con indicación de AIT para ácaros. Aquellos pacientes que no habían aún recibido AIT o llevaban menos de seis dosis, fueron incluidos como controles, y aquellos que llevaban más de 24 dosis de AIT, fueron incluidos como casos. Se evaluó la sensibilización a camarón mediante prueba cutánea con extracto completo de camarón y/o IgE específica a camarón. RESULTADOS: En total, 68 pacientes fueron incluidos; 47 casos y 21 controles. Al calcular el odds ratio de la sensibilización de acuerdo al tiempo con la inmunoterapia, observamos que no había diferencias entre el grupo de casos y controles (OR 0,76 95% IC 0,26 a 2,22 p 0,7 por técnica de MacNemar). Factores como el consumo o no de camarón y la frecuencia de consumo, no parecen estar relacionados con el desenlace. CONCLUSIÓN: A diferencia de lo reportado con extractos acuosos, observamos de AIT con extractos polimerizados para no es un factor de riesgo para la sensibilización a camarón. Es necesario reproducir estos resultados con un mayor tamaño de muestra que permita explorar otros factores.
Assuntos
Dessensibilização Imunológica , Penaeidae , Pyroglyphidae , Humanos , Animais , Masculino , Feminino , Pyroglyphidae/imunologia , Adulto , Penaeidae/imunologia , Adolescente , Adulto Jovem , Criança , Pessoa de Meia-Idade , Polimerização , Rinite Alérgica/terapia , Antígenos de Dermatophagoides/imunologia , Imunoglobulina E/imunologiaRESUMO
PURPOSE OF REVIEW: Helminth infections modify the natural history of allergic diseases, by either decreasing or increasing their symptoms. Several helminth components are involved in the increasing of the allergic response and symptoms, overcoming the concomitant immunosuppression of helminthiases. However, the role of individual IgE-binding molecules in this process remains to be defined. RECENT FINDINGS: We updated the list of helminth allergens and IgE-binding molecules, their effects on asthma presentation, and their impact on allergy diagnosis. Data from genetic and epigenetic studies of ascariasis are analyzed. A new species-specific A. lumbricoides allergen has been discovered, with potential use in molecular diagnosis. Most helminth IgE-binding components are not officially classified as allergens in the WHO/IUIS database, although there is evidence of their influence increasing allergic manifestations. Further immunological characterization of these components is needed to better understand their mechanisms of action and evaluate the ways in which they can influence the diagnosis of allergy.
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Asma , Hipersensibilidade , Parasitos , Animais , Humanos , Alérgenos , Imunoglobulina E , Hipersensibilidade/diagnóstico , Asma/diagnósticoRESUMO
Only few allergens derived from house dust mite (HDM) species have been evaluated in terms of their potential to induce allergic inflammation. In this study, we aimed to evaluate different aspects of the allergenicity and allergenic activity of Blo t 2, a Blomia tropicalis allergen. Blo t 2 was produced as a recombinant protein in Escherichia coli. Its allergenic activity was tested in humans by skin prick test and basophil activation assays, and in mice, by passive cutaneous anaphylaxis and a model of allergic airway inflammation. Sensitization rate to Blo t 2 (54.3%) was similar to that found to Blo t 21 (57.2%) and higher than to Der p 2 (37.5%). Most Blo t 2-sensitized patients showed a low intensity response (99.5%). Blo t 2 elicited CD203c upregulation and allergen induced skin inflammation. Additionally, immunized animals produced anti-Blo t 2 IgE antibodies and passive transfer of their serum to non-immunized animals induced skin inflammation after allergen exposure. Immunized animals developed bronchial hyperreactivity and a strong inflammatory lung reaction (eosinophils and neutrophils). These results confirm the allergenic activity of Blo t 2 and supports its clinical relevance.
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Alérgenos , Pyroglyphidae , Humanos , Camundongos , Animais , Dermatophagoides pteronyssinus , Imunoglobulina E , Inflamação , Antígenos de DermatophagoidesRESUMO
Sublingual immunotherapy (SLIT) is used worldwide to treat house dust mites (HDM) allergy. Epitope specific immunotherapy with peptide vaccines is used far less, but it is of great interest in the treatment of allergic reactions, as it precludes the drawbacks of allergen extracts. The ideal peptide candidates would bind to IgG, blocking IgE-binding. To better elucidate IgE and IgG4 epitope profiles during SLIT, sequences of main allergens, Der p 1, 2, 5, 7, 10, 23 and Blo t 5, 6, 12, 13, were included in a 15-mer peptide microarray and tested against pooled sera from 10 patients pre- and post-1-year SLIT. All allergens were recognized to some extent by at least one antibody isotype and peptide diversity was higher post-1-year SLIT for both antibodies. IgE recognition diversity varied among allergens and timepoints without a clear tendency. Der p 10, a minor allergen in temperate regions, was the molecule with more IgE-peptides and might be a major allergen in populations highly exposed to helminths and cockroaches, such as Brazil. SLIT-induced IgG4 epitopes were directed against several, but not all, IgE-binding regions. We selected a set of peptides that recognized only IgG4 or were able to induce increased ratios of IgG4:IgE after one year of treatment and might be potential targets for vaccines.
Assuntos
Alergia a Ácaros , Imunoterapia Sublingual , Humanos , Animais , Alérgenos , Epitopos , Imunoglobulina G , Imunoglobulina E , Peptídeos , Antígenos de Dermatophagoides , PyroglyphidaeRESUMO
BACKGROUND AND OBJECTIVES: Blomia tropicalis sensitization is associated with asthma in different tropical and sub-tropical countries; however, information about the specific molecular components associated with this disease is scarce. Using molecular diagnosis, we sought to identify B. tropicalis allergens associated with asthma in Colombia. METHODS: Specific IgE (sIgE) to eight B. tropicalis recombinant allergens (Blo t 2/5/7/8/10/12/13 and 21) was determined using an in-house developed ELISA system in asthmatic patients (n=272) and control subjects (n=298) recruited in a national prevalencestudy performed in Colombian cities (Barranquilla, Bogotá, Medellín, Cali and San Andrés). Sample study included children and adults (mean age: 28±SD 17 years old). Cross-reactivity between Blot 5 and Blo t 21 was evaluated by ELISA-inhibition. RESULTS: Sensitization to Blo t 21 (aOR: 1.9; 95% CI: 1.2 - 2.9) and Blo t 5 (aOR: 1.6; 95%CI: 1.1 - 2.5), but not Blo t 2, was associated with asthma. sIgE levels to Blo t 21 and to Blo t 5 were significantly higher in the disease group. Cross-reactivity between Blo t 21 and Blo t 5 is on average moderate; however, individual analysis indicates that may be high (>50%) in some cases. CONCLUSIONS: Although Blo t 5 and Blo t 21 has been described as common sensitizers, this is the first report of their association with asthma. Both components should be included in molecular panels for allergy diagnosis in the tropics.
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Background: Allergen Immunotherapy (AIT) is an effective treatment of allergic respiratory diseases induced by the inhalation of house dust mite allergens. Objectives: To evaluate the efficacy and safety of glutaraldehyde polymerized allergen extracts using a mixture of Dermatophagoides pteronyssinus, D. farinae and Blomia tropicalis in mite allergic individuals residing in Colombia. Methods: Two hundred and fifty (250) patients with allergic rhinoconjunctivitis with, or without asthma and sensitized to D. pteronyssinus, D. farinae and B. tropicalis were included. A glutaraldehyde-modified extract containing a mixture of D. pteronyssinus, D. farinae and B. tropicalis was employed, using a cluster up-dosing schedule followed by a monthly maintenance dose. The primary endpoints to evaluate the clinical impact were the Combined Symptom and Medication Scores (CSMS) for allergic rhinitis, the Asthma Control Test (ACT) and the reduction in medication consumption. Results: Significant improvement was found after 3 months of treatment regarding CSMS (p < 0.0001) and ACT (p < 0.0001). Additionally, a significant decrease in medication consumption was found after 3 months of treatment (p < 0.0001). Adverse reactions, either local or systemic were mild and no severe reactions related to the vaccines were observed. Conclusion: After 12 months of allergen immunotherapy, glutaraldehyde-modified mixture of D. pteronyssinus, D. farinae and B. tropicalis proved to be safe and effective in the treatment of patients with rhinoconjunctivitis with or without asthma due to allergy to mites.
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BACKGROUND: Atopic dermatitis is associated with the production of IgE antibodies against environmental allergens and allergens of the house dust miteDermatophagoides farinae are frequently implicated in the disease. OBJECTIVES: We aimed to observe the allergen-specific IgE against crudeD. farinae, Der f 2 and Zen 1 in dogs with atopic dermatitis and report if these dogs are in contact with material that could shelter mite allergens. METHODS: 100 dogs with clinical diagnosis of atopic dermatitis were included after exclusion of other forms of pruritic skin disease and dogs that already received specific or non-specific immunotherapy. These dogs were of different breeds and ages and they were presented at a veterinary teaching hospital and a private service of veterinary dermatology, both located in Curitiba, Southern Brazil. At the time of anamnesis, some questions were applied to know the possibility of these dogs having had contact with furniture and textile material which could shelter house dust mites. Sera samples were obtained and further analyzed by ELISA assay to measure serum IgE levels against these allergens with an established cut-off of 0.200 IgE optical density. RESULTS: The allergen-specific IgE positivity against crudeD. farinae (92 %) and Zen 1 (77 %) was higher than Der f 2 (56 %). There was a correlation in sensitization to crude D. farinae and Zen 1 that was not observed between crude D. farinae and Der f 2 and Der f 2 and Zen 1. The sensitization to D. farinae and its allergens was associated with an unrestricted exposition to furniture and textile material. CONCLUSION & CLINICAL RELEVANCE: dogs with atopic dermatitis are frequently sensitized to D. farinae and its allergens, Der f 2 and Zen 1, may be considered major allergens in these dogs. Zen 1 may be the main allergen responsible for the sensitization to crude D. farinae.
Assuntos
Alérgenos/imunologia , Dermatite Atópica/veterinária , Dermatophagoides farinae/imunologia , Doenças do Cão/imunologia , Imunização/normas , Imunoglobulina E/sangue , Alérgenos/administração & dosagem , Alérgenos/classificação , Animais , Antígenos de Dermatophagoides/administração & dosagem , Antígenos de Dermatophagoides/imunologia , Proteínas de Artrópodes/administração & dosagem , Proteínas de Artrópodes/imunologia , Brasil , Misturas Complexas/administração & dosagem , Misturas Complexas/imunologia , Dermatite Atópica/imunologia , Dermatophagoides farinae/química , Cães , Feminino , Hospitais Veterinários , Imunização/métodos , MasculinoRESUMO
INTRODUCTION: Aqueous allergen injections, an effective and century-old technique, is considered a second-line approach in daily clinical practice. Inconveniences still surround conventional subcutaneous immunotherapy (SCIT) administration, such as a need for frequent injections, prolonged up-dosing schedules, elevated costs, and the unlikely possibility of a systemic reaction. The intradermal immunotherapy route (IDR) might favorably impact many of the aforementioned issues (Table 1). House dust mite (HDM) allergens are the main perennial sensitizers in the tropics, and as such, are solely employed in immunotherapy treatments. METHODS: We carried out a year-long real-life study in 25 perennial allergic rhinitis children, symptomatic on exposure to house dust, employing an intradermal low-dose allergen mix consisting of 50 ng of Dermatophagoides pteronyssinus/Dermatophagoides farinae and 120 ng of Blomia tropicalis, under a unique cost-wise protocol. Basal symptoms/signs and face Visual Analog Scale (fVAS) scores were recorded for 2 weeks and later compared with those registered throughout the 1-year treatment. Serum-specific IgG4 and IL-10 levels were employed in the assessment of the immune responses. RESULTS: Symptoms/signs and fVAS scores were significantly reduced from days 42 and 49, respectively, and remained so until treatment completion. Increases in specific IgG4's and IL-10 levels reflected significant immune responses. Injections were well tolerated and families reported improved health status (quality of life, QoL). CONCLUSIONS: A unique cost-effective immunotherapy alternative for deprived allergic communities in tropical settings is depicted; further research is needed.
Assuntos
Alérgenos/administração & dosagem , Antígenos de Dermatophagoides/administração & dosagem , Dessensibilização Imunológica/economia , Rinite Alérgica Perene/terapia , Adolescente , Alérgenos/imunologia , Animais , Antígenos de Dermatophagoides/imunologia , Criança , Pré-Escolar , Análise Custo-Benefício , Dermatophagoides farinae/imunologia , Dermatophagoides pteronyssinus/imunologia , Dessensibilização Imunológica/métodos , Países em Desenvolvimento , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Injeções Intradérmicas , Interleucina-10/sangue , Interleucina-10/imunologia , Masculino , Qualidade de Vida , Rinite Alérgica Perene/sangue , Rinite Alérgica Perene/diagnóstico , Rinite Alérgica Perene/imunologia , Índice de Gravidade de Doença , Testes Cutâneos , Resultado do Tratamento , Clima TropicalRESUMO
Background: In autoimmune vasculitis, autoantibodies to Human Proteinase 3 (PR3), a human serine protease, seems to have a role on the inception of c-ANCA associated vasculitis. The origin of this autoreactive response remains unclear. However, for several autoreactive responses, molecular mimicry between environmental antigens and human proteins is key to trigger autoantibodies and finally autoimmunity manifestations. Considering that PR3 is a serine protease and house dust mite (HDM) group 3 allergens share this biochemical activity, the aim of this study was to identify cross-reactive epitopes between serine proteases from human and mites using an in silico approach. Methods: Multi alignment among amino acid sequences of PR3 and HDM group 3 allergens was performed to explore identity and structural homology. ElliPro and BepiPred in silico tools were used to predict B and T cell epitopes. Consurf tool was used to conduct identification of conserved regions in serine proteases family. Results: PR3 and HDM group 3 allergens shared moderate identity and structural homology (root mean square deviation < 1). One B cell cross reactive epitope among serine proteases was identified (29I, 30V, 31G, 32G, 34E, 36K, 37A, 38L, 39A and 54C) and two T cell epitopes. Conclusions: PR3 have structural homology and share cross reactive epitopes with HDM group 3 allergens.
Assuntos
Alérgenos , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Anticorpos Anticitoplasma de Neutrófilos , Autoanticorpos , Autoantígenos , Epitopos de Linfócito B , Epitopos de Linfócito T , Humanos , Mieloblastina , Serina ProteasesRESUMO
Background: Epigenetic changes in response to allergen exposure are still not well understood. The aim of this study was to evaluate histone acetylation levels in peripheral blood leukocytes from humans naturally infected by intestinal parasites and perennially exposed to house dust mites (HDM). Methods: Peripheral blood mononuclear cells (PBMCs) were isolated by gradient centrifugation from 20 infected and 21 non-infected individuals living in a rural/village in Colombia. Histone 3 acetylation (H3Ac) and histone 4 acetylation (H4Ac) levels were measured in six immune genes previously associated with helminth immunity by chromatin immunoprecipitation (ChIP)-quantitative PCR. Then we analyzed the association between histone acetylation levels with total parasite egg burden and IgE levels. Results: We found an inverse correlation between H4Ac levels in the IL13 gene and egg worm burden that remained significant after adjustment by age [-0.20 (-0.32 to -0.09), p < 0.0001]. Moreover, we found significant associations between H4Ac levels in IL4 [0.32 (0.05-0.60), p = 0.02] and CHI3L1 [0.29 (0.08-0.51), p = 0.008] with the IgE levels to Ascaris lumbricoides. In addition, the levels of specific IgE antibodies to HDM were associated with H4Ac levels in the gene TNFSF13B encoding the B cell activating factor (BAFF) [0.51 (0.26-0.76), p < 0.001]. All values are presented as beta (95% CI). Conclusion: Histone acetylation levels at key type-2 immune genes in humans were modified by nematode infection and HDM allergens and are associated with the intensity of the IgE response.
Assuntos
Anticorpos Anti-Helmínticos/imunologia , Antígenos de Dermatophagoides/imunologia , Ascaríase/imunologia , Ascaris/imunologia , Fator Ativador de Células B/genética , Proteína 1 Semelhante à Quitinase-3/genética , Histonas/metabolismo , Imunoglobulina E/imunologia , Interleucina-4/genética , Pyroglyphidae/imunologia , Acetilação , Adolescente , Adulto , Animais , Ascaríase/sangue , Ascaríase/epidemiologia , Ascaríase/parasitologia , Criança , Pré-Escolar , Estudos de Coortes , Colômbia/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Cross-reactivity between allergens and human proteins could have a clinical impact in allergic diseases. Blo t 13 is an allergen from the mite Blomia tropicalis, which belongs to the fatty acid binding protein (FABP) family and has structural homology with human FABPs. This work aimed to map B cell epitopes on Blo t 13 and to identify epitopes involved in cross-reactivity with human heart FABP (FABP3) and adipocyte FABP (FABP4). Sera from 25 patients with house dust mite (HDM) allergy that were sensitized to Blo t 13 were used for testing the reactivity of immunoglobulin E (IgE) and IgG to FABP. The epitope mapping of Blo t 13 was performed using overlapping peptides, and cross-reactivity between Blo t 13 and human FABP was analyzed using human sera and anti-Blo t 13 monoclonal antibodies. IgE antibodies to all FABPs were detected in 14/25 serum samples, and IgG was detected in 25/25 serum samples. The cross-reactivity of Blo t 13 was 42% with FABP3 and 48% with FABP4. Two IgE-binding regions were identified in Blo t 13; one between residues 54 and 72 (the main cross-reacting region) and another between residues 111 to 129. Our results suggest that exposure to the Blo t 13 allergen could induce an auto-reactive response to endogenous FABP in allergic patients sensitized to Blo t 13.
Assuntos
Alérgenos/metabolismo , Epitopos de Linfócito B/imunologia , Proteína 3 Ligante de Ácido Graxo/imunologia , Proteínas de Ligação a Ácido Graxo/imunologia , Proteínas de Ligação a Ácido Graxo/metabolismo , Adipócitos/metabolismo , Alérgenos/genética , Alérgenos/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Reações Cruzadas , Mapeamento de Epitopos , Proteína 3 Ligante de Ácido Graxo/química , Proteína 3 Ligante de Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/química , Proteínas de Ligação a Ácido Graxo/genética , Feminino , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/patologia , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Masculino , Ácaros/metabolismo , Miocárdio/metabolismo , Estrutura Terciária de Proteína , Alinhamento de SequênciaRESUMO
Environmental variations induced by industrialization and climate change partially explain the increase in prevalence and severity of allergic disease. One possible mechanism is the increase in allergen production leading to more exposure and sensitization in susceptible individuals. House dust mites (HDMs) are important sources of allergens inducing asthma and rhinitis, and experimentally they have been demonstrated to be very sensitive to microenvironment modifications; therefore, global or regional changes in temperature, humidity, air pollution or other environmental conditions could modify natural HDM growth, survival and allergen production. There is evidence that sensitization to HDMs has increased in some regions of the world, especially in the subtropical and tropical areas; however, the relationship of this increase with environmental changes is not so clear as has reported for pollen allergens. In this review, we address this point and explore the effects of current and predicted environmental changes on HDM growth, survival and allergen production, which could lead to immunoglobulin E (IgE) sensitization and allergic disease prevalence. We also assess the role of adjuvants of IgE responses, such as air pollution and helminth infections, and discuss the genetic and epigenetic aspects that could influence the adaptive process of humans to drastic and relatively recent environmental changes we are experiencing.
RESUMO
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
Canine atopic dermatitis (CAD) is a common dermatosis, defined as a genetic-related disease which predisposes to skin inflammation and pruritus, associated to a IgE-specific response in most of cases. Clinical diagnosis may be later complemented by skin allergy and/or serological tests. The aim of these tests is to identify possible allergens in order to enable the clinicians to select candidate antigens for allergen specific immunotherapy. In the present study 58 CAD positive animals were tested. All were submitted to the intradermal test (IDT) and screened for the presence of antibodies against different antigens using ELISA. The obtained results show a high prevalence of sensitization among the tested dogs to house dust mites and to pollen ofC. dactylon. With this work it was possible to identify the main allergens involved in immunological response of dogs with CAD living in central area of Rio Grande do Sul(AU)
A dermatite atópica canina (DAC) é uma dermatose comum, definida como doença de cunho genético que predispõe à inflamação e ao prurido cutâneo, associados à resposta IgE específica na maior parte dos casos. O diagnóstico da DAC é clínico e pode ser posteriormente complementado por testes alérgicos cutâneos e/ou sorológicos. O objetivo desses testes é identificar possíveis alérgenos e, com isso, possibilitar ao clínico a seleção de antígenos candidatos para a imunoterapia alérgeno-específica. No presente estudo, foram testados 58 animais diagnosticados para DAC. Todos os animais foram submetidos ao teste cutâneo intradérmico (TID), e amostras de sangue foram coletadas para a realização de testes sorológicos. Os resultados obtidos demonstraram elevada prevalência de sensibilização aos ácaros domiciliares e ao pólen da gramínea C. dactylon nos cães testados. Com este trabalho, foi possível identificar os principais alérgenos envolvidos na resposta imunológica de cães atópicos residentes na região central do Rio Grande do Sul(AU)
Assuntos
Animais , Cães , Dermatite Atópica/imunologia , Dermatite Atópica/veterinária , Pyroglyphidae/imunologia , Acaridae/imunologia , Testes Intradérmicos/veterinária , Testes Sorológicos/veterinária , Ensaio de Imunoadsorção Enzimática/veterináriaRESUMO
Canine atopic dermatitis (CAD) is a common dermatosis, defined as a genetic-related disease which predisposes to skin inflammation and pruritus, associated to a IgE-specific response in most of cases. Clinical diagnosis may be later complemented by skin allergy and/or serological tests. The aim of these tests is to identify possible allergens in order to enable the clinicians to select candidate antigens for allergen specific immunotherapy. In the present study 58 CAD positive animals were tested. All were submitted to the intradermal test (IDT) and screened for the presence of antibodies against different antigens using ELISA. The obtained results show a high prevalence of sensitization among the tested dogs to house dust mites and to pollen ofC. dactylon. With this work it was possible to identify the main allergens involved in immunological response of dogs with CAD living in central area of Rio Grande do Sul.
A dermatite atópica canina (DAC) é uma dermatose comum, definida como doença de cunho genético que predispõe à inflamação e ao prurido cutâneo, associados à resposta IgE específica na maior parte dos casos. O diagnóstico da DAC é clínico e pode ser posteriormente complementado por testes alérgicos cutâneos e/ou sorológicos. O objetivo desses testes é identificar possíveis alérgenos e, com isso, possibilitar ao clínico a seleção de antígenos candidatos para a imunoterapia alérgeno-específica. No presente estudo, foram testados 58 animais diagnosticados para DAC. Todos os animais foram submetidos ao teste cutâneo intradérmico (TID), e amostras de sangue foram coletadas para a realização de testes sorológicos. Os resultados obtidos demonstraram elevada prevalência de sensibilização aos ácaros domiciliares e ao pólen da gramínea C. dactylon nos cães testados. Com este trabalho, foi possível identificar os principais alérgenos envolvidos na resposta imunológica de cães atópicos residentes na região central do Rio Grande do Sul.
Assuntos
Animais , Cães , Acaridae/imunologia , Dermatite Atópica/imunologia , Dermatite Atópica/veterinária , Pyroglyphidae/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Testes Intradérmicos/veterinária , Testes Sorológicos/veterináriaRESUMO
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
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...