Japanese Cedar Pollen-Specific IgA in Nasal Secretions and Nasal Allergy Symptoms.

To our knowledge, this is the first study to show an association between nasal symptoms and rIgA in nasal secretions, suggesting that rIgA is useful as an antigen-specific biomarker for allergic rhinitis or pollinosis. Furthermore, rIgA values in nasal secretions do not increase in asymptomatic participants sensitized to Japanese cedar during the pollen season.