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1.
Life (Basel) ; 14(6)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38929634

RESUMEN

Allergic conjunctivitis is an allergen-induced immune response secondary to the binding of immunoglobulin-E (IgE) to sensitized mast cells. Approximately 40% of North Americans and 20% of the world's population are impacted by some form of allergy and it continues to increase in prevalence, especially among children. Specified IgE antibodies can be found in almost all cases of exposure to seasonal or perennial allergens. Activation and degranulation of mast cells lead to increased tear levels of histamine, tryptase, leukotrienes, cytokines, and prostaglandins. The release of these factors initiates the recruitment of inflammatory cells in the conjunctival mucosa, which causes the late-phase reaction. Signs and symptoms of ocular allergies include itching, tearing, chemosis, and hyperemia, which can lead to decreased productivity and poor quality of life. Many treatment options are available to improve symptoms, including, mast cell stabilizers, antihistamines, dual-acting agents, steroids, nonsteroidal anti-inflammatory drugs (NSAIDS), and other off-label treatment modalities. This review article provides an overview of different types of allergic conjunctivitis, its pathology and immunology, and recommended methods of treatment.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38768897

RESUMEN

BACKGROUND: Assessment of IgE-mediated sensitization to flour allergens is widely used to investigate flour-induced occupational asthma. The diagnostic efficiency of detecting specific IgE antibodies (sIgEs) against wheat and rye flour, however, has not been thoroughly compared with other diagnostic procedures. OBJECTIVE: We sought to evaluate the diagnostic accuracy of sIgE against wheat and rye compared with specific inhalation challenge (SIC) with flour as the reference standard. METHODS: This retrospective multicenter study included 264 subjects who completed an SIC with flour in eight tertiary centers, of whom 205 subjects showed a positive SIC result. RESULTS: Compared with SIC, sIgE levels of 0.35 kUA/L or greater against wheat and rye provided similar sensitivities (84% to 85%, respectively), specificities (71% to 78%), positive predictive values (91% to 93%), and negative predictive values (56% to 61%). Increasing the threshold sIgE value to 5.10 kUA/L for wheat and to 6.20 kUA/L for rye provided a specificity of 95% or greater and further enhanced the positive predictive value to 98%. Among subjects with a positive SIC, those who failed to demonstrate sIgE against wheat and rye (n = 26) had significantly lower total serum IgE level and blood and sputum eosinophil counts and a lesser increase in postchallenge FeNO compared with subjects with a detectable sIgE. CONCLUSION: High levels of sIgE against wheat and/or rye flour strongly support a diagnosis of flour-induced occupational asthma without the need to perform an SIC. The absence of detectable sIgE against wheat and rye in subjects with a positive SIC seems to be associated with lower levels of TH2 biomarkers.

3.
J Allergy Clin Immunol ; 153(1): 182-192.e7, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37748654

RESUMEN

BACKGROUND: Despite their central role in peanut allergy, human monoclonal IgE antibodies have eluded characterization. OBJECTIVE: We sought to define the sequences, affinities, clonality, and functional properties of human monoclonal IgE antibodies in peanut allergy. METHODS: We applied our single-cell RNA sequencing-based SEQ SIFTER discovery platform to samples from allergic individuals who varied by age, sex, ethnicity, and geographic location in order to understand commonalities in the human IgE response to peanut allergens. Select antibodies were then recombinantly expressed and characterized for their allergen and epitope specificity, affinity, and functional properties. RESULTS: We found striking convergent evolution of IgE monoclonal antibodies (mAbs) from several clonal families comprising both memory B cells and plasmablasts. These antibodies bound with subnanomolar affinity to the immunodominant peanut allergen Ara h 2, specifically a linear, repetitive motif. Further characterization of these mAbs revealed their ability to single-handedly cause affinity-dependent degranulation of human mast cells and systemic anaphylaxis on peanut allergen challenge in humanized mice. Finally, we demonstrated that these mAbs, reengineered as IgGs, inhibit significant, but variable, amounts of Ara h 2- and peanut-mediated degranulation of mast cells sensitized with allergic plasma. CONCLUSIONS: Convergent evolution of IgE mAbs in peanut allergy is a common phenomenon that can reveal immunodominant epitopes on major allergenic proteins. Understanding the functional properties of these molecules is key to developing therapeutics, such as competitive IgG inhibitors, that are able to stoichiometrically outcompete endogenous IgE for allergen and thereby prevent allergic cascade in cases of accidental allergen exposure.


Asunto(s)
Hipersensibilidad al Cacahuete , Humanos , Animales , Ratones , Epítopos Inmunodominantes , Antígenos de Plantas , Glicoproteínas , Inmunoglobulina E , Epítopos , Anticuerpos Monoclonales , Alérgenos , Arachis , Albuminas 2S de Plantas
4.
Front Allergy ; 4: 1270326, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37901762

RESUMEN

Introduction: Allergic reactions are mediated by human IgE antibodies that bind to and cross-link allergen molecules. The sites on allergens that are recognized by IgE antibodies have been difficult to investigate because of the paucity of IgE antibodies in a human serum. Here, we report the production of unique human IgE monoclonal antibodies to major inhaled allergens and food allergens that can be produced at scale in perpetuity. Materials and methods: The IgE antibodies were derived from peripheral blood mononuclear cells of symptomatic allergic patients, mostly children aged 3-18 years, using hybridoma fusion technology. Total IgE and allergen-specific IgE was measured by ImmunoCAP. Their specificity was confirmed through ELISA and immunoblotting. Allergenic potency measurements were determined by ImmunoCAP inhibition. Biological activity was determined in vitro by comparing ß-hexosaminidase release from a humanized rat basophilic cell line. Results: Human IgE monoclonal antibodies (n = 33) were derived from 17 allergic patients with symptoms of allergic rhinitis, asthma, atopic dermatitis, food allergy, eosinophilic esophagitis, or red meat allergy. The antibodies were specific for five inhaled allergens, nine food allergens, and alpha-gal and had high levels of IgE (53,450-1,702,500 kU/L) with ratios of specific IgE to total IgE ranging from <0.01 to 1.39. Sigmoidal allergen binding curves were obtained through ELISA, with low limits of detection (<1 kU/L). Allergen specificity was confirmed through immunoblotting. Pairs of IgE monoclonal antibodies to Ara h 6 were identified that cross-linked after allergen stimulation and induced release of significant levels of ß-hexosaminidase (35%-80%) from a humanized rat basophilic cell line. Conclusions: Human IgE monoclonal antibodies are unique antibody molecules with potential applications in allergy diagnosis, allergen standardization, and identification of allergenic epitopes for the development of allergy therapeutics. The IgE antibody probes will enable the unequivocal localization and validation of allergenic epitopes.

5.
Int Arch Allergy Immunol ; 184(9): 875-881, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37402353

RESUMEN

INTRODUCTION: Some grass species that are either common or widely spread in Thailand have not been used for pollen allergy diagnosis. In order to improve diagnostic accuracy, the aim of this pilot study was to identify the grass species responsible for pollen allergy in Thailand. METHODS: The skin sensitization of pollen extracts from six different grass species, including rice (Oryza sativa), corn (Zea mays), sorghum (Sorghum bicolor), para grass (Urochloa mutica), ruzi grass (Urochloa eminii), and green panic grass (Megathyrsus maximus), was evaluated by skin prick test (SPT). Serum's IgE specific to each pollen extract was analyzed by Western blot (WB). The ImmunoCAPTM test for Johnson grass was also evaluated. RESULTS: Of the thirty-six volunteers who participated in this study, eighteen tested positive for at least one of the diagnostic tests, namely SPT, WB analysis, or ImmunoCAPTM. Notably, skin reactivity to para grass, corn, sorghum, and rice was more commonly observed compared to ruzi grass and green panic grass. However, in the WB analysis, individuals with pollen-specific IgE were more frequently detected in sorghum, green panic grass, corn, rice, and ruzi grass than para grass. CONCLUSION: In this pilot investigation, our findings indicate that the pollen extracts of rice, corn, sorghum, and para grass are associated with pollen allergy in Thailand. These results contribute to the current knowledge on the identification of grass species that are associated with pollen allergy in Thailand and Southeast Asia.


Asunto(s)
Oryza , Rinitis Alérgica Estacional , Humanos , Rinitis Alérgica Estacional/diagnóstico , Proyectos Piloto , Alérgenos , Tailandia/epidemiología , Inmunoglobulina E , Pruebas Cutáneas/métodos , Extractos Vegetales , Poaceae
6.
Medicina (Kaunas) ; 58(6)2022 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-35744079

RESUMEN

Chronic spontaneous urticaria (CSU) considerably alters patients' quality of life, often for extended periods, due to pruriginous skin lesions, impaired sleep, unexpected development of angioedema, and failure of conventional treatments in properly controlling signs and symptoms. Recent research focused on the development of new therapeutic agents with higher efficacy. Although the production of specific immunoglobulin E (IgE) antibodies against certain allergens is not a characteristic of the disease, treatment with omalizumab, a monoclonal anti-IgE antibody, proved efficient and safe in patients with moderate to severe chronic spontaneous urticaria uncontrolled by H1-antihistamines. Ligelizumab, a high-affinity monoclonal anti-IgE antibody, may also efficiently relieve symptoms of unresponsive chronic urticaria to standard therapies. This comprehensive review aims to present recently acquired knowledge on managing chronic spontaneous urticaria with new anti-IgE antibodies. We conducted extensive research on the main databases (PubMed, Google Scholar, and Web of Science) with no restrictions on the years covered, using the search terms "anti-IgE antibodies", "omalizumab", "ligelizumab", and "chronic spontaneous urticaria". The inclusion criteria were English written articles, and the exclusion criteria were animal-related studies. ClinicalTrials.gov was also reviewed for recent relevant clinical trials related to CSU treatment. CSU is a challenging disease with a significant effect on patients' quality of life. Current therapies often fail to control signs and symptoms, and additional treatment is needed. New biologic therapies against IgE antibodies and FcεRIα receptors are currently under investigation in advanced clinical trials. We reviewed recently published data on CSU management using these novel treatments. The development of new and improved treatments for CSU will lead to a more personalized therapeutical approach for patients and provide guidance for physicians in better understanding disease mechanisms. However, some agents are still in clinical trials, and more research is needed to establish the safety and efficacy of these treatments.


Asunto(s)
Antialérgicos , Urticaria Crónica , Urticaria , Animales , Antialérgicos/uso terapéutico , Anticuerpos Antiidiotipos , Enfermedad Crónica , Urticaria Crónica/tratamiento farmacológico , Humanos , Inmunoglobulina E , Omalizumab/uso terapéutico , Calidad de Vida , Urticaria/tratamiento farmacológico
7.
Clin Exp Allergy ; 52(2): 324-333, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34570395

RESUMEN

BACKGROUND: Deaths attributed to Coronavirus Disease 2019 (COVID-19) are mainly due to severe hypoxemic respiratory failure. Although the inflammatory storm has been considered the main pathogenesis of severe COVID-19, hypersensitivity may be another important mechanism involved in severe cases, which have a perfect response to corticosteroids (CS). METHOD: We detected the serum level of anti-SARS-CoV-2-spike S1 protein-specific IgE (SP-IgE) and anti-SARS-CoV-2 nucleocapsid protein-specific IgE (NP-IgE) in COVID-19. Correlation of levels of specific IgE and clinical severity were analysed. Pulmonary function test and bronchial provocation test were conducted in early convalescence of COVID-19. We also obtained histological samples via endoscopy to detect the evidence of mast cell activation. RESULT: The levels of serum SP-IgE and NP-IgE were significantly higher in severe cases, and were correlated with the total lung severity scores (TLSS) and the PaO2 /FiO2 ratio. Nucleocapsid protein could be detected in both airway and intestinal tissues, which was stained positive together with activated mast cells, binded with IgE. Airway hyperresponsiveness (AHR) exists in the early convalescence of COVID-19. After the application of CS in severe COVID-19, SP-IgE and NP-IgE decreased, but maintained at a high level. CONCLUSION: Hypersensitivity may be involved in severe COVID-19.


Asunto(s)
Bronquios/inmunología , COVID-19/inmunología , Proteínas de la Nucleocápside de Coronavirus/inmunología , Duodeno/inmunología , Hipersensibilidad/inmunología , Inmunoglobulina E/inmunología , Mastocitos/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bronquios/metabolismo , Bronquios/patología , COVID-19/metabolismo , COVID-19/patología , COVID-19/fisiopatología , Estudios de Casos y Controles , Proteínas de la Nucleocápside de Coronavirus/metabolismo , Duodeno/metabolismo , Duodeno/patología , Femenino , Humanos , Hipersensibilidad/metabolismo , Hipersensibilidad/patología , Hipersensibilidad/fisiopatología , Pulmón/fisiopatología , Masculino , Mastocitos/metabolismo , Mastocitos/patología , Persona de Mediana Edad , Membrana Mucosa/inmunología , Membrana Mucosa/metabolismo , Membrana Mucosa/patología , Fosfoproteínas/inmunología , Fosfoproteínas/metabolismo , Recuperación de la Función , Hipersensibilidad Respiratoria/fisiopatología , Estudios Retrospectivos , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Glicoproteína de la Espiga del Coronavirus/metabolismo , Adulto Joven
8.
Allergol Int ; 71(1): 117-124, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34481729

RESUMEN

BACKGROUND: Measurement of allergen-specific IgE antibodies to inhaled allergens is important for the diagnosis and risk evaluation of allergic diseases such as asthma and allergic rhinitis. This study aimed to elucidate the prevalence of allergen sensitization among the healthy population in Japan using serum samples stocked in the Japanese Red Cross for blood donation. METHODS: Age- and gender-stratified serum samples (n = 800) from residents in Tokyo aged 20-59 years were randomly selected from the stocked serum obtained for blood donation in 2005. Total and specific IgE antibodies to 17 inhaled allergens were measured by the ImmunoCAP method. Individuals with positive (≥0.35 UA/mL) specific IgE antibodies to at least one inhaled allergen were defined as atopic. Stocked serums from donors aged 20-29 years in Sapporo, Osaka, Fukuoka, and Okinawa (n = 200 each) were also obtained for the measurement of IgE to six common inhaled allergens, to evaluate regional differences in the rate of positivity. RESULTS: Among residents in Tokyo, the prevalence of atopy was 78.0% and highest in men aged 20-29 years (94.0%), which decreased with age. The prevalence of specific IgE antibodies was highest for Japanese cedar pollen (66.8%), followed by cypress pollen (46.8%), Dermatophagoides pteronyssinus (38.3%), and moths (30.1%). Examination of IgE to Japanese cedar pollen, D. pteronyssinus, and moths identified 97.6% of atopic subjects in Tokyo. There were substantial regional differences in the prevalence of pollen IgE positivity. CONCLUSIONS: This study demonstrated an extremely high prevalence of positivity in inhaled allergen-specific IgE antibodies among healthy adults in Japan.


Asunto(s)
Alérgenos/inmunología , Inmunoglobulina E/inmunología , Hipersensibilidad Respiratoria/epidemiología , Adulto , Alérgenos/sangre , Femenino , Humanos , Inmunoglobulina E/sangre , Japón/epidemiología , Masculino , Persona de Mediana Edad , Polen/efectos adversos , Prevalencia
9.
Biomedicines ; 9(11)2021 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-34829798

RESUMEN

The increased incidence of allergies and asthma has sparked interest in IgE, the central player in the allergic response. Interaction with its high-affinity receptor FcεRI leads to sensitization and allergen presentation, extracellular membrane-proximal domain in membrane IgE can act as an antigen receptor on B cells, and the interaction with low-affinity IgE receptor CD23 additionally influences its homeostatic range. Therapeutic anti-IgE antibodies act by the inhibition of IgE functions by interfering with its receptor binding or by the obliteration of IgE-B cells, causing a reduction of serum IgE levels. Fusion proteins of antibody fragments that can act as bispecific T-cell engagers have proven very potent in eliciting cytotoxic T-lymphocyte-mediated killing. We have tested five anti-IgE Fc antibodies, recognizing different epitopes on the membrane-expressed IgE, for the ability to elicit specific T-cell activation when expressed as single-chain Fv fragments fused with anti-CD3ε single-chain antibody. All candidates could specifically stain the cell line, expressing the membrane-bound IgE-Fc and bind to CD3-positive Jurkat cells, and the specific activation of engineered CD3-overexpressing Jurkat cells and non-stimulated CD8-positive cells was demonstrated for 8D6- and ligelizumab-based bispecific antibodies. Thus, such anti-IgE antibodies have the potential to be developed into agents that reduce the serum IgE concentration by lowering the numbers of IgE-secreting cells.

10.
Open Access Rheumatol ; 12: 127-131, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32765129

RESUMEN

A 67-year-old Caucasian female presented in August 2019 to our rheumatology service, with 3 days history of severe neck pain and right-sided headache with aches in both shoulders and arms and mild stiffness. Other symptoms included mild jaw claudication. She had recently returned from Majorca after an uneventful two-week trip. She had a background of severe allergic asthma and allergic rhinitis, well controlled with omalizumab which was started in 2016, based on persistently high IgE. Her sister suffers from a type of vasculitis and is currently on steroids. The patient is an ex-smoker and drinks two bottles of wine a week. She had high inflammatory markers with raised eosinophilic count and was admitted for further work up to rule out infection and to commence steroid after for a likely diagnosis of eosinophilic granulomatosis with polyangiitis. Shortly after admission to the acute assessment unit, she became confused and febrile. An extensive work up ruled out infection, and she was started on steroids and treated for acute hyponatremia. Omalizumab was stopped. She improved and was discharged on a tapering dose of steroids and was weaned off completely within 4 months. Her inflammatory markers returned to normal as well as her eosinophilic count, with complete resolution of her presenting symptoms.

11.
Nutrients ; 12(8)2020 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-32784846

RESUMEN

BACKGROUND: Maternal diet has significant effects on development of childhood atopic disease and hypersensitivity development. However, the gestational dysfunctions demanding special diets are becoming a widespread phenomenon, their immunological implications can be manifested in the profile of antibodies in the offspring's serum. METHODS: 153 allergic and 150 healthy individuals were diagnosed for allergy using specific antibody and cytokine immunoassay tests. The medical history of subjects along with mothers' course of pregnancy was completed by allergologist's anamnesis. A self-organizing neural network and multivariate analyses to complex data and pick basic interactions were used. RESULTS: Two significant explanatory modules were determined. The first was formed by gestational diabetic and cholestatic diet, infant formula feeding type, probiotic supplementation and its BMI index, moderate IgE, increased IgG levels of antibodies and single or poly-food allergy type (7 clusters). The second was formed by gestational vegan/vegetarian and elimination diet, maternal probiotic supplementation, sex, high IgE total antibodies and food and mixed poly-allergy to aero- and food-origin allergens (19 clusters). CONCLUSIONS: Significant associations were observed between special gestational diet intake underlying foetal programming and the mechanisms of childhood allergy. The novelty is the positive association between diabetic and cholestatic diet intake and IgE/IgG-mediated food hypersensitivity.


Asunto(s)
Autoanticuerpos/sangre , Hipersensibilidad/inmunología , Fenómenos Fisiologicos Nutricionales Maternos/inmunología , Efectos Tardíos de la Exposición Prenatal/inmunología , Probióticos/uso terapéutico , Adulto , Autoanticuerpos/inmunología , Niño , Preescolar , Dieta/efectos adversos , Dieta/métodos , Femenino , Hipersensibilidad a los Alimentos/sangre , Hipersensibilidad a los Alimentos/inmunología , Humanos , Hipersensibilidad/sangre , Inmunoglobulina E/inmunología , Inmunoglobulina G/inmunología , Análisis Multivariante , Redes Neurales de la Computación , Embarazo , Efectos Tardíos de la Exposición Prenatal/sangre
12.
Klin Lab Diagn ; 65(7): 435-438, 2020 Jun 04.
Artículo en Ruso | MEDLINE | ID: mdl-32762182

RESUMEN

Personalized therapy for female infertility means determining of immune mechanisms, including allergic sensitization towards sperm antigens. In order to determine antisperm serum IgE antibodies in women with infertility suffering from pelvic inflammatory diseases, the modified Anti-Spermatozoa Antibody protocol was used (ASA Serum ELISA, Demeditec Diagnostisc, Germany). The modification of the protocol is designed to detect only serum antisperm IgE antibodies carrying Fab fragments to sperm antigens. Allergen-specific IgEs to a common panel of 176 respiratory and food allergenic molecules were determined using the MeDALL scientific chip developed as a part of the European project. Forty patients suffering from infertility of inflammatory etiology and 16 practically healthy women of reproductive age were examined. Specific IgE antibodies towards sperm antigens were detected in blood serum in 7/40 (17.5%) patients with infertility. The maximum level of sIgE was 4 times higher than the maximal value of fertile women. No correlation with total IgE was detected. Women with sIgE-ASA complained of burning and itching immediately after coition. Systemic and long-term allergic reactions were not noted. Women with positive sIgE-ASA values were 2 times more likely to suffer from chronic recurrent vaginal dysbiosis. The presence of specific anti-sperm IgE antibodies is likely to have pathogenetic significance in female infertility, and they should be taken into consideration for creating personalized therapy approaches.


Asunto(s)
Infertilidad Femenina , Enfermedad Inflamatoria Pélvica , Antígenos , Femenino , Humanos , Inmunoglobulina E/análisis , Infertilidad Femenina/inmunología , Masculino , Enfermedad Inflamatoria Pélvica/inmunología , Espermatozoides/inmunología
13.
J Allergy Clin Immunol Pract ; 8(10): 3311-3321, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32653647

RESUMEN

There is convincing evidence that tight relationships between the upper and lower airways also apply to the workplace context. Most patients with occupational asthma (OA) also suffer from occupational rhinitis (OR), although OR is 2 to 3 times more common than OA. OR most often precedes the development of OA, especially when high-molecular-weight protein agents are involved, and longitudinal cohort studies have confirmed that OR is associated with an increased risk for the development of OA. The level of exposure to sensitizing agents at the workplace is the most important determinant for the development of IgE-mediated sensitization and OR. Atopy is a risk factor for the development of IgE-mediated sensitization only to high-molecular-weight agents. In workers with work-related rhinitis symptoms, documentation of IgE-mediated sensitization to a workplace agent via skin prick testing or serum specific IgE confirms a diagnosis of probable OR, whereas specific nasal provocation testing in the laboratory remains the reference method to establish a definite diagnosis of OR. Complete avoidance of exposure to the causal agent is the most effective therapeutic option for controlling work-related nasal symptoms and preventing the development of OA. If complete elimination of exposure is expected to induce meaningful adverse socioeconomic consequences, reduction of exposure can be considered as an alternative approach, but it is important to consider the individual risk factors for the development of OA to implement a more personalized management of OR.


Asunto(s)
Asma Ocupacional , Enfermedades Profesionales , Exposición Profesional , Rinitis , Asma Ocupacional/diagnóstico , Asma Ocupacional/epidemiología , Humanos , Inmunoglobulina E , Estudios Longitudinales , Enfermedades Profesionales/diagnóstico , Enfermedades Profesionales/epidemiología , Exposición Profesional/efectos adversos , Rinitis/diagnóstico , Rinitis/epidemiología
14.
Ann Biol Clin (Paris) ; 78(3): 329-342, 2020 06 01.
Artículo en Francés | MEDLINE | ID: mdl-32420887

RESUMEN

Accreditation of an in vitro diagnostic assay according to the NF/EN/ISO 15189 standard requires to analyze its technical performance before implementation for routine use, and annually when reviewing effectiveness of quality controls. Performance is evaluated through repeatability, intermediate fidelity, accuracy and uncertainty of measurement. The coefficients of variation (CV) of the intra-assay and inter-assay precision tests must be compared with those of "peers" (results from laboratories employing the same method) and also with those obtained with "all methods", i.e., results from all laboratories performing the same assay, irrespective of the method. To our best knowledge, there is currently no French or international recommendation on what the acceptable limits of performance for specific IgE and tryptase assays should be. Therefore, the AllergoBioNet network of hospital allergy laboratories set out to characterize the performance of their current methods as a basis for the development of recommendations. The results provided by 24 centers were analyzed and led to consensus recommendations for specific IgE, total IgE and tryptase assays.


Asunto(s)
Bioensayo/métodos , Inmunoglobulina E/análisis , Triptasas/análisis , Acreditación , Bioensayo/normas , Consenso , Pruebas Diagnósticas de Rutina/métodos , Pruebas Diagnósticas de Rutina/normas , Francia , Humanos , Laboratorios/normas , Control de Calidad , Reproducibilidad de los Resultados
15.
Clin Chim Acta ; 504: 119-124, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32035852

RESUMEN

Immediate drug hypersensitivity reactions (IDHRs) constitute a significant health problem that may be compounded by consequences of diagnostic error. In daily practice, IDHR diagnostic work up starts with drug-specific skin testing and/or quantification of specific IgE (sigE) antibodies in serum. Here we critically review the performance, i.e. potential and limitations of sIgE to ß-lactam antibiotics (ß-LABs), curarizing neuromuscular blocking agents (NMBAs), opiates and (semi)synthetic opioids, fluoroquinolones (FQs), poppy seed (papaver somniferum), chlorhexidine and finally Hevea latex. Quintessence of these studies is clear. Quantification of these drug-specific sIgE should not be used in isolation to document or exclude diagnosis of an IDHR. False negative results entail the risk for subsequent potentially life-threatening anaphylaxis upon re-exposure. False positive results lead to erroneous avoidance and unnecessary substitutions and fails to identify the true etiology.


Asunto(s)
Anafilaxia , Hipersensibilidad a las Drogas , Hipersensibilidad Inmediata , Hipersensibilidad a las Drogas/diagnóstico , Humanos , Hipersensibilidad Inmediata/inducido químicamente , Hipersensibilidad Inmediata/diagnóstico , Inmunoglobulina E , Pruebas Cutáneas
16.
Anal Bioanal Chem ; 412(8): 1901-1914, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32030491

RESUMEN

Immunoglobin E (IgE)-related allergy constitutes a high proportion in allergic diseases. The production of specific IgE is key to evoking serial cascades and pathological reactions. Thus, targeting IgE is a different therapeutic approach from symptomatic treatments. Monoclonal antibodies (mAbs) against IgE were developed and a humanized antibody, omalizumab, was approved by five countries. It could inhibit the binding of IgE with epsilon receptor I of crystallizable fragment (FcεRI), thus preventing anaphylactic reactions. However, no bioactivity assay, which is the critical quality attribute and should thoroughly reflect the clinical mechanism, has been established to date. In commercial lot release, only the enzyme-linked immunosorbent assay (ELISA) method was applied, which only reflects the binding of omalizumab to IgE but not the subsequent reaction. In scientific research works, human FcεRI-transfected RBL-2H3 cells were used to indicate degranulation based on the detection of ß-hexosaminidase. Nevertheless, this method needs much work to stabilize the response and, hence, is not suitable for routine usage in commercial production and control of antibodies. To evaluate the bioactivity of anti-IgE antibodies including omalizumab using a simple assay that reflects the following mechanism of actions (MOA) after binding, we established an RBL-2H3 cell line transfected with both the α subunit of human FcεRI and nuclear factor-activated T cell (NFAT) response elements, the latter is conjugated with a luciferase gene, which could shed luminescence when substrates exist. The method was proven to possess good specificity, accuracy, linearity, and precision and may be utilized as a supplement to anti-IgE antibody bioactivity assays in terms of development, lot release, stability, and comparability studies. Graphical abstract The mechanism sketch of reporter gene assay for bioactivity determination of anti-IgE antibodies by RBL-2H3/FcεRIα/NFAT-Luc cells (left) and representative curves generated by the reporter gene assay (right).


Asunto(s)
Anticuerpos Antiidiotipos/análisis , Bioensayo/métodos , Genes Reporteros , Animales , Línea Celular Tumoral , Ensayo de Inmunoadsorción Enzimática , Humanos
17.
Clin Immunol ; 209: 108268, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31669191

RESUMEN

The Basophil Activation Test (BAT) is a valuable allergy diagnostic tool but is time-consuming and requires skilled personnel and cumbersome processing, which has limited its clinical use. We therefore investigated if a microfluidic immunoaffinity BAT (miBAT) technique can be a reliable diagnostic method. Blood was collected from allergic patients and healthy controls. Basophils were challenged with negative control, positive control (anti-FcεRI), and two concentrations of a relevant and non-relevant allergen. CD203c and CD63 expression was detected by fluorescent microscopy and flow cytometry. In basophils from allergic patients the CD63% was significantly higher after allergen activation as compared to the negative control (p<.0001-p=.0004). Activation with non-relevant allergen showed equivalent CD63% expression as the negative control. Further, the miBAT data were comparable to flow cytometry. Our results demonstrate the capacity of the miBAT technology to measure different degrees of basophil allergen activation by quantifying the CD63% expression on captured basophils.


Asunto(s)
Basófilos/inmunología , Hipersensibilidad/inmunología , Alérgenos/inmunología , Femenino , Citometría de Flujo/métodos , Humanos , Inmunoensayo/métodos , Masculino , Microfluídica/métodos , Hidrolasas Diéster Fosfóricas/inmunología , Tetraspanina 30/inmunología
19.
Expert Rev Respir Med ; 12(9): 745-754, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30141696

RESUMEN

INTRODUCTION: Omalizumab is a monoclonal antibody that binds and inhibits free serum immunoglobulin E, a mediator involved in the clinical manifestations of allergic asthma. Evidence for its efficacy and safety in the treatment of moderate-to-severe allergic asthma is based primarily on studies in adolescents and adults. However, there is increasing evidence of its utility in children with allergic asthma aged 6-12 years. Areas covered: This article reviews efficacy, safety, and effectiveness of omalizumab in the treatment of moderate-to-severe allergic asthma in children aged 6-12 years in clinical trials and in studies in clinical practice. Pharmacoeconomic aspects of its use among this population and the positioning of omalizumab in pediatric asthma management guidelines are also discussed. Additionally, an algorithm for the management of poorly controlled severe pediatric asthma in children older than 6 years is proposed. Electronic databases, such as PubMed, were searched for terms Asthma and Omalizumab and for asthma management guidelines. Expert commentary: Add-on omalizumab is an effective maintenance therapy in children aged 6-12 years with poorly controlled moderate-to-severe allergic asthma treated with medium-high inhaled corticosteroids doses and inhaled long-acting ß2-agonists. Omalizumab appears safe in children in both clinical trials and real-life setting and may be cost-effective.


Asunto(s)
Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Omalizumab/uso terapéutico , Antiasmáticos/economía , Niño , Análisis Costo-Beneficio , Humanos , Omalizumab/economía
20.
Int Arch Allergy Immunol ; 176(3-4): 249-254, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29870996

RESUMEN

BACKGROUND: Wheat allergy is the third most common food allergy that develops during infancy in Japan. To identify factors associated with persistent wheat allergy, we assessed the rate of tolerance acquisition among Japanese children aged less than 6 years with an immediate-type wheat allergy using the oral food challenge (OFC) method. METHODS: This retrospective cohort study included 83 children (born in 2005-2006) who had a history of immediate-type allergic reaction to wheat and were followed until 6 years of age. The subjects were divided to form "tolerant" (n = 55; tolerance acquired by 6 years of age) and "allergic" (n = 28; tolerance not acquired by 6 years of age) groups based on their OFC results. RESULTS: The rates of tolerance acquisition to 200 g of udon noodles at 3, 5, and 6 years of age were 20.5% (17/83), 54.2% (45/83), and 66.3% (55/83), respectively. The total number of anaphylactic reactions experienced prior to 3 years of age in response to all foods (p < 0.01) and to wheat (p = 0.043) was significantly higher in the allergic than in the tolerant group. Wheat- and ω-5 gliadin-specific immunoglobulin E (IgE) levels were significantly higher in the allergic group than in the tolerant group (p < 0.01), and wheat-specific IgE levels were more likely to increase after infancy in the allergic group. CONCLUSIONS: A history of anaphylaxis to all foods including wheat and/or a high level of wheat- or ω-5 gliadin-specific IgE antibodies were identified as risk factors for persistent wheat allergy.


Asunto(s)
Hipersensibilidad al Trigo/etiología , Niño , Preescolar , Femenino , Humanos , Tolerancia Inmunológica , Inmunoglobulina E/sangre , Lactante , Masculino , Estudios Retrospectivos , Triticum/inmunología , Hipersensibilidad al Trigo/inmunología
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