Allergen challenge‐induced acute exudation of IL‐8, ECP and α(2)‐macroglobulin in human rhinovirus‐induced common colds

Greiff, L.; Andersson, M.; Svensson, C; Linden, M; Myint, S; Persson, C.G.a

Rhinovirus infections cause exacerbations of eosinophilic airway disease. The acute effects of allergen‐challenge on nasal interleukin‐8 (IL‐8), eosinophil cationic protein (ECP), and α(2)‐macroglobulin were examined in atopic subjects with common cold symptoms. Twenty‐three patients with seasonal allergic rhinitis were inoculated with human rhinovirus 16 outside the pollen season. Diluent and allergen challenges, followed by nasal lavages, were carried out about 3 months before and 4 days after virus inoculation. Seventeen patients developed significant common cold symptoms with increased nasal lavage fluid levels of α(2)‐macroglobulin, IL‐8, and ECP at baseline (p<0.001–0.05 versus before inoculation), and were further increased by allergen challenge (p<0.001–0.05); IL‐8 and ECP levels were correlated (r=0.63, p<0.001). Before inoculation, the six patients who later did not develop common cold symptoms had high levels of IL‐8 and myeloperoxidase (MPO), and exhibited strong allergen‐induced plasma exudation responses (α(2)‐macroglobulin). After inoculation, IL‐8 and ECP did not increase in these symptomless subjects. In conclusion, high nasal interleukin‐8 and myeloperoxidase levels and exudative hyperresponsiveness may protect against infection. The association between nasal interleukin‐8 and eosinophil cationic protein in common cold, particularly that observed in nasal lavage fluids after allergen‐induced acute exudation of plasma, suggests the involvement of interleukin‐8 in exacerbation of airway mucosal eosinophil activity.