IL5RA and allergic rhinitis: Our group and others have illustrated the involvement of Eo/B progenitors in allergic inflammatory disease in the following studies: i) increases in circulating Eo/B CFU in subjects with atopy and allergic rhinitis [1,4]; ii) increases in circulating Eo/B CFU during seasonal exposure to allergens [5,6]; iii) increases in circulating and bone marrow progenitors and upregulation of IL-5Rα expression after allergen inhalation challenge [7-10] and iv) increases in airway CD34+ cells expressing the IL-5Rα after allergen inhalation [11].