Résumé : Knockout mice studies have revealed that NF-κB plays a critical role in Th2 cell differentiation and is therefore required for induction of allergic airway inflammation. However, the questions of whether NF-κB also plays a role in the effector phase of airway allergy and whether inhibiting NF-κB could have therapeutic value in the treatment of established asthma remain unanswered. To address these issues, we have assessed in OVA-sensitized wild-type mice the effects of selectively antagonizing NF-κB activity in the lungs during OVA challenge. Intratracheal administration of NF-κB decoy oligodeoxynucleotides to OVA-sensitized mice led to efficient nuclear transfection of airway immune cells, but not constitutive lung cells and draining lymph node cells, associated with abrogation of NF-κB activity in the airways upon OVA provocation. NF-κB inhibition was associated with strong attenuation of allergic lung inflammation, airway hyperresponsiveness, and local production of mucus, IL-5, IL-13, and eotaxin. IL-4 and OVA-specific IgE and IgG1 production was not reduced. This study demonstrates for the first time that activation of NF-κB in local immune cells is critically involved in the effector phase of allergic airway disease and that specific NF-κB inhibition in the lungs has therapeutic potential in the control of pulmonary allergy.