Increased Levels of IL-2 and IL-4 in Stimulated Adenoidal Lymphocytes of Atopic Children

Abstract

Background: The adenoid is involved in the defence against airway pathogens and its surface is also exposed to airborne allergens. The knowledge about reactions taking place in the lymphatic tissue of this organ is, however, limited. To elucidate the influence of atopy we investigated the cellular and cytokine profile of in vitro-stimulated adenoid lymphocytes. Methods: Adenoid tissue cells from 13 atopic and 8 non-atopic children were cultured and stimulated with ionomycin and 4β-phorbol 12-myristate 13-acetate. Supernatants were collected after 4 and 20 h of stimulation and interleukin-2 (IL-2), IL-4 and interferon-γ (IFN-γ) were analysed by ELISA. Flow cytometry was used to quantify the leukocyte markers CD3, CD19, CD25 and HLA-DR. Results: Increased levels of IL-2 and IL-4 but not IFN-γ were detected in the supernatants of adenoid cell cultures from atopic children after 20 h of stimulation (p < 0.05) and a significant correlation with a positive regression between IL-2 and IL-4 was found. Atopy was also associated with a greater increase in the percentage of CD19-positive B cells after stimulation (p < 0.05). Conclusions: A difference in the reactivity of adenoidal lymphoid cells in children was observed between atopic and non-atopic subjects. Atopy was associated with an increased production of IL-2 and IL-4 as well as a more pronounced increase of B cells.