Identification of an allergenic calmodulin from Amaranthus palmeri pollen.

INTRODUCTION: Pollens are an important source of allergens that trigger rhinitis or asthma. The allergenic extracts of pollens used to diagnose and treat allergies contain different allergenic antigens. Isolated allergenic proteins are employed in in vitro assays, skin tests and allergenic-specific immunotherapy. Calcium-binding allergens are clinically relevant antigens, and their allergenicity can be affected by Ca2+ binding. In this work, a calmodulin was identified as an allergen from Amaranthus palmeri pollen, an important source of pollinosis in Europe, Asia and North America. MATERIALS AND METHODS: Allergenic calmodulin from A. palmeri pollen was isolated by size-exclusion chromatography and reverse-phase chromatography and identified by mass spectrometry. Sensitization to isolated calmodulin was evaluated by skin prick tests in patients with allergy to A. palmeri pollen. RESULTS: Size-exclusion chromatography yielded two fractions that were recognized by the IgE of patients allergic to A. palmeri pollen. Mass spectrometry analysis of the fractions from reverse-phase chromatography showed peptide sequences that identified a calmodulin. Skin prick tests showed that the isolated calmodulin was recognized by 56% of patients allergic to A. palmeri pollen. CONCLUSION: A. palmeri pollen calmodulin could be a clinically relevant allergen in patients sensitized to this source.

[The prevalence of sensitization to cockroaches. Experience of an allergy service]. / Prevalencia de sensibilización a cucaracha. Experiencia de un servicio de alergia.

BACKGROUND: Allergy skin prick tests are important tools for the diagnosis of respiratory allergic diseases. Cockroach antigens have been identified as the cause of rhinitis, asthma, and other allergic diseases. OBJECTIVE: To show that the cockroach antigen participates in the cause of allergic diseases. METHODS: A retrolective and cross-sectional study was carried out, for which clinical records and history of atopy were reviewed; the results were obtained from blood biometry, nasal cytology, total IgE, and coproparasitoscopic serial tests. After prior informed consent, skin tests were applied in 3-74 year-old patients. RESULTS: 1,837 patients were studied; the prevalence of cutaneous reactivity to the cockroach antigen was of 17.90%; 56% of the patients had a diagnosis of allergic rhinitis, and only 6% had been diagnosed with asthma and rhinitis. CONCLUSION: The application of the cockroach antigen in skin tests must be considered in the practice of all allergists.

Antecedentes: Las pruebas cutáneas por técnica de punción son herramientas importantes para el diagnóstico de la alergia respiratoria. Se han identificado los antígenos de las cucarachas como responsables del desarrollo de rinitis, asma y otras enfermedades alérgicas. Objetivo: Demostrar la participación del antígeno de cucaracha en enfermedades alérgicas. Métodos: Se llevó a cabo un estudio retrolectivo y transversal, para el cual se revisaron historias clínicas y los antecedentes de atopia; se recolectaron los resultados de biometría hemática, citología nasal, IgE total y estudio coproparasitoscópico seriado. Previo consentimiento informado se aplicaron pruebas cutáneas en pacientes de tres a 74 años. Resultados: Se estudiaron 1837 pacientes, la prevalencia de reactividad cutánea al antígeno de cucaracha fue de 17.90 %; 56 % de los pacientes tenía diagnóstico de rinitis alérgica y solo 6 %, de asma y rinitis. Conclusión: Se debe considerar la aplicación del antígeno de cucaracha en las pruebas cutáneas en la práctica del alergólogo.