Respiratory system is a biological system for gas exchange in our body to make sure your breathing is working properly. The respiratory epithelium, starting from the nose to the lungs, also serves as barrier to protect from the foreign antigens, such as allergens and microorganisms. After the stimulation from allergens, the airway epithelial cells can rapidly release type 2 alarmins, such as interleukin 25(IL-25), interleukin 33(IL-33) and thymic stromal lymphopoietin (TSLP), which activate the type 2 immune cells, like type 2 innate lymphoid cells (ILC2s), T helper 2 cells (TH2 cells), and mast cells to produce type 2 cytokines, including IL-4, IL-5 and IL-13. Subsequently, the elevation of type 2 cytokines initiated eosinophilic inflammation and tissue remodeling in the respiratory diseases with type 2 inflammation, including asthma, allergic rhinitis, chronic rhinosinusitis, and chronic obstructive pulmonary disease (COPD). Recent clinical trials have demonstrated the potential of biologics targeting these type 2 alarmins for the treatment of type 2 inflammatory diseases.
Although promising efficacy of biologics targeting IL-33 and TSLP in allergic diseases has confirmed their role in the pathogenesis of allergic diseases, the regulatory mechanisms of their production in the respiratory epithelium remains unclarified, such as the transcription, translation or post-translational modifications of IL-25, IL-33 and TSLP in the physiologic or pathologic conditions. Moreover, the functional regulation of their effector cells including Th2 cells and ILC2 cells deserves further exploration. The regulation pathways of epithelial cell derived alarmins as well as their effector cells will not only give us a better understanding of the type 2 inflammatory diseases, but also provide new strategies to manage the diseases.
The aim of the current Research Topic is to cover the promising, recent, and novel research about the regulation of alarmins in respiratory and other systems. Areas to be covered in this Research Topic may include, but are not limited to:
• The transcription, translation or post-translation of IL-25, IL-33, TSLP and their receptors.
• The production and functional role of epithelial derived IL-25, IL-33, and TSLP in respiratory diseases with type 2 inflammation.
• Therapeutic approaches targeting IL-25, IL-33, and TSLP in respiratory diseases with type 2 inflammation.
• The regulation of Th2 and ILC2 cells by alarmins in type 2 inflammation.
• Alarmins in other systems, such as liver, brain, intestine etc.
• The function of other alarmins, such as HMGB1, Defensin, Cathelicidin in respiratory inflammation.
Keywords: Alarmins, type 2 inflammation, ILC2, Th2, biologics
Important note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.
