Fig. 1

Der p 1 (cystine protease) is a proteolytic trigger of an activation cascade involving several other allergenic proteins, including Der p 3 (trpypsin), Der p 6 (chymotrpypsin), and Der p 9 (Collagenolytic serine protease). These enzymatic activities facilitate the release of mite allergens into the digestive tract of the mite and affects the generation of protein fragments available to antigen processing. Microbial compounds from endosymbiotic bacteria also participate to the formation of fecel pellets, which are expelled onto the airway epithelium. Release of proinflammatory cytokines (IL-6, IL-8, GM-CSF, thymic stromal lymphopoietin, and IL-25), alarmins (IL-1α and IL-33) and chemoattractants (CCL2 and CCL20) by airway epithelial cells follows