Type 2 immunity in asthma

Abstract

Type 2-immunity represents the typical adaptive response to allergen exposure in atopic individuals. It mainly involves Th2 cells and immunoglobulin E, as the main orchestrators of type 2-inflammation. Recently, it has been highlighted that allergens may be responsible for a Th2 response beside specific IgE activation and that a number of other environmental stimuli, such as viruses and pollutants, can trigger the same pattern of inflammation beyond atopy. Emerging data sustain a substantial role of the so-called epithelial dysfunction in asthma pathogenesis, both from anatomic and functional point of view. Furthermore an increasing amount of evidence demonstrates the relevance of innate immunity in polarizing a Th2 impaired response in asthmatic patients. Under this perspective, the complex cross-talking between airway epithelium, innate and adaptive immunity is emerging as a major determinant of type 2-inflammation beyond allergens.This review will include an update on the relevance of dysregulation of innate and adaptive type 2-immunity in asthma pathogenesis, particularly severe asthma, and on the role of the allergens that are associated with severe asthma. Type 2-immunity also will be reviewed in the light of the current and upcoming targeted treatments for severe asthma.

One year of mepolizumab. Efficacy and safety in real-life in Italy

“…In the last decade, several biological treatments were introduced and investigated in the field of severe asthma, with the aim of reducing exacerbations and OCS use. A more and more detailed knowledge of asthma pathophysiology paved the way to the development of targeted molecules, in particular within the frame of Th2 inflammation, which includes interleukin (IL) 4, IL-5, IL-9, IL-13 and airway epithelial cells or innate lymphoid cells-2 [14][15][16][17], In such case, the inflammatory background is responsive to ICS [18], which promote eosinophil apoptosis [19]. Eosinophils exert a pivotal role in bronchial inflammation and represent one of the main targets for biological drugs.…”

Protective activity of mogroside V against ovalbumin‐induced experimental allergic asthma in Kunming mice

“…The pathogenesis of asthma is associated with many factors such as heredity, an immune disorder, and environmental problems. In particular, the severe immune disorder is the main feature of the pathophysiological process of asthma (Caminati, Pham, Bagnasco, & Canonica, ). We first found that mogroside V can attenuate OVA‐induced AHR and decrease the number of inflammation‐related cells (eosinophils and macrophages) in the BALF of asthmatic mice in this study.…”

Monoclonal antibodies for the treatment of severe asthma

“…It is clear from the variation in symptoms, treatment response, impact on lung function and age at onset that the underlying mechanisms, involving many cell types and cytokines, vary between individuals as well as over time . Although these pathways and the interactions of mediators are complex, asthma can be roughly categorised into two types: eosinophilic asthma, the more common, which is associated with a type 2 immune response in which eosinophils and IgE are key contributors; and non‐type 2 non‐eosinophilic asthma, in which neutrophil airway infiltration is dominant or there is little infiltration.…”

“…IL‐4 is involved in the regulation of B cells and IgE synthesis; IL‐5 is essential for the survival and maturation of eosinophils; and the functions of IL‐13 include regulation of IgE synthesis and a role in airway hyper‐responsiveness. Eosinophils also promote the synthesis and release of these and other cytokines …”