Viruses and bacteria in Th2‐biased allergic airway disease

Abstract

Allergic airway diseases are typically characterized by a type 2-biased inflammation. Multiple distinct viruses and bacteria have been detected in the airways. Recently, it has been confirmed that the microbiome of allergic individuals differs from that of healthy subjects, showing a close relationship with the type 2 response in allergic airway disease. In this review, we summarize the recent findings on the prevalence of viruses and bacteria in type 2-biased airway diseases and on the mechanisms employed by viruses and bacteria in propagating type 2 responses. The understanding of the microbial composition and postinfectious immune programming is critical for the reconstruction of the normal microflora and immune status in allergic airway diseases.

Epithelial barrier dysfunctions in atopic dermatitis: a skin-gut-lung model linking microbiome alteration and immune dysregulation

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Tight junction, mucin, and inflammasome‐related molecules are differentially expressed in eosinophilic, mixed, and neutrophilic experimental asthma in mice

“…Patients with neutrophilic and mixed asthma respond poorly to corticosteroid therapy, and increased numbers of neutrophils with persistent eosinophilia are seen in severe asthma and sudden‐onset fatal asthma . In both types of complex phenotypes, other factors such as genetics, epithelial barrier dysfunction, innate immune response, environmental exposures, viral infections, and comorbidities may further modulate inflammation, bringing the stability of dominant physiopathological mechanisms to question . Therefore, better understanding of the characteristics of each inflammatory subgroup is crucial for extensive development of personalized/precision medicine .…”

Distinction between rhinovirus‐induced acute asthma and asthma‐augmented influenza infection

“…However, it is not clear whether this reflects the high frequency of RV infections or particular pathophysiological characteristics of the virus. Furthermore, the role of other respiratory viruses in asthma attacks is not as well documented . Influenza (IFV) is one of the most common respiratory pathogens and is associated with considerable morbidity and severe outcomes in patients with asthma …”

“…as well documented. [4][5][6] Influenza (IFV) is one of the most common respiratory pathogens 7 and is associated with considerable morbidity and severe outcomes in patients with asthma. [8][9][10][11] In this context, key questions arise as follows: Does each respiratory virus have a unique asthma-inciting capacity?…”