Proinflammatory cytokines in nasal secretions of allergic subjects after antigen challenge

To study the role of cytokines in allergic late-phase reactions (LPR), we measured cytokines (interleukins [IL]-1β, IL-2, IL-4, IL-5, IL-6, and granulocyte-macrophage colony-stimulating factor [GM-CSF]) in nasal secretions (NS) of eight allergic subjects following antigen or saline provocation. NS were collected hourly for 10 h after challenge by a newly developed matrix method. All subjects recorded hourly symptom scores. Cytokines were measured using specific enzyme-linked immunosorbent assays (ELISA). Compared with prechallenge values, significant levels of IL-1β were detected in all subjects during the immediate reaction (peak, 51.0 ± 22.4 pg/ml) and LPR (peak, 78.5 ± 22.6 pg/ml) after antigen challenges (p < 0.01) but not saline challenges. In contrast, GM-CSF and IL-6 showed a delayed rise (peak, 26.4 ± 1.3 pg/ml and 33.8 ± 10.0 pg/ml, respectively) at hour 4 in the antigen-challenge period (p < 0.01 versus saline). NS from 4 donors also showed detectable IL-5 (7.6 to 155 pg/ml) during the immediate reaction and LPR after allergen challenges (versus saline, p < 0.01). The levels of cytokine correlated (p < 0.05) with corresponding total symptom scores during the immediate reaction (IL-1β) and LPR (IL-1β, GM-CSF, and IL-6). IL-2 and IL-4 were not detected in any sample. Thus, IL-1β, IL-5, IL-6, and GM-CSF are present in the LPR of allergic rhinitis, and their correlation with clinical responses may suggest their role in allergic inflammation.