Nasal inflammatory mediator release in ragweed allergic rhinitis: correlation with cellular influx into nasal secretions.

Lipid-derived mediators are found in nasal secretions during the early and late phase of allergic responses. To explore this early response further, concentrations of inflammatory mediators were measured along with characterization of specific cell influx during dose-dependent ragweed challenges. Ten allergic rhinitis subjects underwent two unilateral nasal lavages using 3-fold concentrations of short ragweed antigen. Low doses of ragweed (0.016-0.114 units Amb a I) did not provoke cell influx (1 of 18 challenges), whereas moderate doses (0.432-1.3 units Amb a I) induced cell influxes in 7 of 18 and at high doses in 8 of 17 challenges (3.39-11.7 units Amb a I). The differential of the cellular influx was greater than 50% neutrophils in 7 challenges; greater than 50% eosinophils in 3, and a mixed pattern in 6. There was a significant association between the dose of antigen and the level of prostaglandin D2 (PGD2), leukotrienes (LTs) C4, D4 and E4. Challenges with an eosinophilic influx tended to be associated with higher concentrations of mediators than neutrophilic influxes. Similar to the immediate skin response, the early allergic response in the nose demonstrated a cell influx with release of PGD2, LTsC4, D4 and E4. Nasal cellular inflammation therefore can occur within minutes of allergen exposure.