IL-6 secretion by ex vivo whole blood cultures upon allergen stimulation

Allergen induced IL-6 synthesis by whole blood cultures was compared with skin prick allergen test results for the same group of individuals. Whole blood cultures from both allergic and non-allergic individuals secrete IL-6 at high allergen concentrations. When whole blood cultures from controls were incubated with serial dilutions of allergens it was found that IL-6 induction was abolished at lower allergen dilutions (allergen threshold concentration or ATC). When whole blood cultures from patients with allergic rhinitis were stimulated with ATC it was found that some allergens induced IL-6 secretion. The allergens inducing IL-6 and the level of IL-6 secreted were dependent on the patient. The induction of IL-6 secretion by the cultures at ATC correlated very significantly with the patient's skin prick test results (r = 0.71 1; p = 0.0003).