Early growth response protein 1 and dual specificity protein phosphatase 1 are involved in down-regulation of allergic responses

Background The airway epithelium is accepted as an active player in immune responses. Besides its role as physical barrier towards invading pathogens and irritants, epithelium also affects the outcome of the immune response by the production of various pro-inflammatory mediators. We have previously shown that nasal epithelial cells are able to respond to exposure to house dust mite (HDM) allergen and that this response is different for epithelial cells isolated from healthy or from allergic individuals. Expression profiling in allergic individuals relative to healthy ones reveals genes that are permanently activated (e.g. NFKB-1, FOSL-1 and JUN) and genes that fail to be up-regulated (e.g. DUSP-1, EGR-1). As EGR-1 and DUSP-1 have been implicated in the down-regulation of inflammatory responses, we hypothesize that failure of up-regulation of DUSP-1/EGR-1 after exposure to HDM in allergic individuals could be responsible for the sustained activation of the allergic response.