Effector cell signatures in peripheral blood after nasal allergen challenge: biomarkers of the allergic response

This study investigated temporal transcriptomic changes in response to nasal allergen challenge of titrated timothy grass pollen. This is an open single-center observational study conducted outside the pollen season. Twelve participants with seasonal allergic rhinitis underwent a control (diluent) challenge followed by nasal allergen challenge after an interval of 14 days. On each challenge day, nasal challenge with control or titrated timothy grass pollen (Aquagen, phleum pratense; ALK) was administered. Peripheral blood was collected before nasal challenge (baseline) and at 3, 6 and 24 hours following challenge. RNA was extracted from whole blood and CD4 cells for microarray experiment using Affymetrix Human Gene 1.0 ST arrays.