Comprehensive profiling of peripheral immune cells and subsets in patients with intermittent allergic rhinitis compared to healthy controls and after treatment with glucocorticoids.

Intermittent allergic rhinitis (IAR) is a common allergic disease, which is associated with local infiltration of T cells, eosinophils, and basophils. However, changes of circulating inflammatory cells may reflect local and systemic allergic inflammation and potentially, also the response to treatment with glucocorticoids (GCs). In this study, we comprehensively profiled peripheral blood immune cells and subsets from 12 patients with IAR during the birch pollen season before and after GC treatment and nine healthy controls by flow cytometry. Orthogonal partial least squares discriminant analysis (OPLS-DA) identified that peripheral immune cells and subsets markedly separated symptomatic patients and controls. Eosinophils, basophils, and Th2 cells contributed most to the separation. However, there was no good separation between patients before and after GC treatment. Local allergic inflammation in the nasal mucosa is associated with increased circulating Th2 cells, eosinophils, and basophils. Local GC treatment has limited effects on circulating immune cells.