Pulmonary Eosinophils at the Center of the Allergic Space-Time Continuum

Abstract

Eosinophils are typically a minority population of circulating granulocytes being released from the bone-marrow as terminally differentiated cells. Besides their function in the defense against parasites and in promoting allergic airway inflammation, regulatory functions have now been attributed to eosinophils in various organs. Although eosinophils are involved in the inflammatory response to allergens, it remains unclear whether they are drivers of the asthma pathology or merely recruited effector cells. Recent findings highlight the homeostatic and pro-resolving capacity of eosinophils and raise the question at what point in time their function is regulated. Similarly, eosinophils from different physical locations display phenotypic and functional diversity. However, it remains unclear whether eosinophil plasticity remains as they develop and travel from the bone marrow to the tissue, in homeostasis or during inflammation. In the tissue, eosinophils of different ages and origin along the inflammatory trajectory may exhibit functional diversity as circumstances change. Herein, we outline the inflammatory time line of allergic airway inflammation from acute, late, adaptive to chronic processes. We summarize the function of the eosinophils in regards to their resident localization and time of recruitment to the lung, in all stages of the inflammatory response. In all, we argue that immunological differences in eosinophils are a function of time and space as the allergic inflammatory response is initiated and resolved.

Potential Biomarkers of Resilience to Microgravity Hazards in Astronauts

“…Eosinophils, a type of white blood cell, are involved in the initiation and maintenance of allergic inflammation through the release of various mediators, such as cytokines, chemokines, and granule proteins. Elevated eosinophil counts are often associated with allergic diseases, such as asthma, allergic rhinitis, and atopic dermatitis [ 40 ]. Therefore, maintaining normal ranges of eosinophils could indicate resilience against hypersensitivity reactions in the microgravity environment.…”

Montelukast: results and prospects for applications in pediatric practice

“…[19], а затем и на людях [20]. Недавно была описана роль LTC4 в опосредовании транспорта эозинофилов из легких в паратрахеальные лимфатические узлы при экспериментальной аллергической БА [21]. Активация CysLT1 важна для эозинофильного воспаления, поскольку она усиливает экспрессию молекул эндотелиальной адгезии, индуцирует хемотаксис эозинофилов и снижает их апоптоз [12,22].…”

Emerging Roles of Platelets in Allergic Asthma

“…Eosinophilic infiltration of the airway has been established as a hallmark of allergic asthma. Mounting evidence indicates that eosinophils migrate to the bronchial tissue during the late-phase asthmatic response (62,63) and secrete large amounts of toxic proteins and proinflammatory mediators, leading to bronchoconstriction, airway hyperresponsiveness, and mucus overproduction (3). Importantly, eosinophil recruitment from the circulation requires their activation (64,65), which has been reported to be positively associated with platelet activation in asthmatic airways (66,67).…”