Peripheral blood neutrophil activity during Dermatophagoides pteronyssinus-induced late-phase airway inflammation in patients with allergic rhinitis and asthma.

Recent investigations suggest that neutrophils may play an important role in the late-phase allergen-induced inflammation in allergic airway diseases. The aim of this study was to evaluate neutrophil chemotaxis, phagocytic activity, and reactive oxygen species (ROS) production in patients with allergic rhinitis and asthma challenged with inhaled Dermatophagoides pteronyssinus. Eighteen patients with allergic rhinitis and 14 with allergic asthma, all sensitized to D. pteronyssinus, as well as 15 healthy individuals underwent bronchial challenge with D. pteronyssinus. Peripheral blood collection and neutrophil isolation were performed 24 h before as well as 7 and 24 h after bronchial challenge. Neutrophils chemotaxis, phagocytic activity, and ROS production were analyzed by flow cytometer. Neutrophil chemotaxis and ROS production were increased, while phagocytic activity was decreased 24 h before challenge in patient groups compared with healthy individuals. After challenge, neutrophil chemotaxis and phagocytic activity increased after 7 and 24 h, when ROS production, only after 24 h. Bronchial allergen challenge had no influence for neutrophils activity in healthy subjects. Activated chemotaxis, phagocytic activity, and ROS production of peripheral blood neutrophils after challenge with D. pteronyssinus reflect an enhanced systemic inflammation in allergic rhinitis and asthma patients with induced late-phase airway inflammation.