The role of allergy in the development of airway inflammation in children

The initiation of the allergic inflammation involves the presentation of the processed allergen to the naı̈ve T-cells by antigen-presenting cells (APC). In the presence of an appropriate cytokine milieu, a T-helper type 2 (Th2) cell polarisation is favoured. Re-exposure to allergen results in the cross-linking of IgE on mast cells and basophils, leading to the early response in which pro-inflammatory mediators and cytokines are released. This is followed by the recruitment of eosinophils, monocytes, neutrophils and other inflammatory cells, causing airway oedema and mucous plugging. Recurrent exposure to allergen leads to a state of chronic inflammation characterised by smooth muscle hypertrophy and tissue remodelling. TGF-β, transforming growth factor-beta; IL, interleukin; GM-CSF, granulocyte-macrophage colony-stimulating factor; Ag, antigen; STAT-6, signal transducer and activator of transcription; C-maf, transcription factors; GATA 3; MHC-II/Ag/TcR, Major Histocompatibility Complex, Antigen, T-cell receptor; CD.

Factors that promote and protect against the development of allergic airway inflammation. IFN-γ, interferon-gamma.