Airway Epithelium Plays a Leading Role in the Complex Framework Underlying Respiratory Allergy.

Airway epithelium is the cellular structure with the greatest surface exposed to a plethora of environmental airborne substances, including microorganisms, respiratory viruses, air pollutants, and allergens. In addition to being a protective physical barrier at the air-liquid interface, the airway epithelium acts as an effective chemical and immunological barrier that plays a crucial role in orchestrating the immune response in the lungs, by supporting the activation, recruitment, and mobilization of immune cells. Airway epithelium dysfunction has been clearly associated with various airway inflammatory diseases, such as allergic asthma. Although it is not fully understood why a person develops respiratory allergy, a growing body of evidence shows that the nature of the host's immune response is strongly determined by the state of the airway epithelium at the time of contact with the inhaled allergen. Our review highlights the physiological state of airway epithelium as a key element in the development of allergy and, particularly, in exacerbation of asthma. We review the role of physiological oxidants as signaling molecules in lung biology and allergic diseases and examine how high exposure to air pollutants (eg, cigarette smoke and diesel particles) can contribute to the increased incidence of respiratory allergy and exacerbation of the disease.

Egg proteins as allergens and the effects of the food matrix and processing.

Hen eggs are an important and inexpensive source of high-quality proteins in the human diet. Egg, either as a whole or its constituents (egg yolk and white), is a key ingredient in many food products by virtue of its nutritional value and unique functional properties, such as emulsifying, foaming, and gelling. Nevertheless, egg is also known because of its allergenic potential and, in fact, it is the second most frequent source of allergic reactions, particularly in children. This review deals with the structural or functional properties of egg proteins that make them strong allergens. Their ability to sensitize and/or elicit allergic reactions is linked to their resistance to gastroduodenal digestion, which ultimately allows them to interact with the intestinal mucosa where absorption occurs. The factors that affect protein digestibility, whether increasing it, decreasing it, or inducing a different proteolysis pattern, and their influence on their capacity to induce or trigger an allergic reaction are discussed. Special attention is paid to the effect of the food matrix and the processing practices on the capacity of egg proteins to modulate the immune response.

Airway epithelium plays a leading role in the complex framework underlying respiratory allergy

Airway epithelium is the cellular structure with the greatest surface exposed to a plethora of environmental airborne substances, including microorganisms, respiratory viruses, air pollutants, and allergens. In addition to being a protective physical barrier at the air-liquid interface, the airway epithelium acts as an effective chemical and immunological barrier that plays a crucial role in orchestrating the immune response in the lungs, by supporting the activation, recruitment, and mobilization of immune cells. Airway epithelium dysfunction has been clearly associated with various airway inflammatory diseases, such as allergic asthma. Although it is not fully understood why a person develops respiratory allergy, a growing body of evidence shows that the nature of the host's immune response is strongly determined by the state of the airway epithelium at the time of contact with the inhaled allergen. Our review highlights the physiological state of airway epithelium as a key element in the development of allergy and, particularly, in exacerbation of asthma. We review the role of physiological oxidants as signaling molecules in lung biology and allergic diseases and examine how high exposure to air pollutants (eg, cigarette smoke and diesel particles) can contribute to the increased incidence of respiratory allergy and exacerbation of the disease (AU)

El epitelio pulmonar constituye la barrera celular más susceptible a la acción deletérea de la multitud de agentes que se encuentran en el ambiente, incluidos los alérgenos. Además de prevenir su acceso al organismo, la barrera epitelial de las vías respiratorias juega un papel inmunomodulador crucial, regulando de forma local la acción de las células del sistema inmune subyacentes. Una disfunción epitelial, provocada tanto directa como indirectamente por la acción de los aeroalérgenos, parece ser una de las causas principales de desregulación de la homeostasis pulmonar, causando una respuesta proinflamatoria descontrolada que cada vez más autores atribuyen al origen de las reacciones alérgicas. En esta revisión se quiere destacar el papel de la barrera epitelial pulmonar como regulador de la respuesta inmune en el contexto de la alergia. Las enfermedades crónicas que afectan a las vías respiratorias, tales como el asma alérgica, muestran frecuentemente una función epitelial defectuosa, apoyando así la hipótesis antes mencionada que subyace al origen de la alergia. El impacto de otros contaminantes ambientales -como virus respiratorios, bacterias, humo del tabaco y partículas diésel- sobre la integridad epitelial, así como su influencia en la biología redox pulmonar relacionada con el desarrollo de la respuesta alérgica, también se abordarán en la presente revisión (AU)