Changes in serum hypoxia-inducible factor-1α and erythropoietin in allergic rhinitis patients: Correlation with the Th inflammatory profile and disease comorbidities.

Objectives: The balance between proinflammatory IFN-γ Th1 vs. the anti-inflammatory allergy-mediating IL-4-heralded Th2 reactions is pivotal in IgE-mediated allergic rhinitis (AR). Hypoxia-Inducible Factor (HIF)-1α is inducible by hypoxia and various cytokines.