PT - JOURNAL ARTICLE AU - Dubucquoi, S AU - Desreumaux, P AU - Janin, A AU - Klein, O AU - Goldman, M AU - Tavernier, J AU - Capron, A AU - Capron, M TI - Interleukin 5 synthesis by eosinophils: association with granules and immunoglobulin-dependent secretion. AID - 10.1084/jem.179.2.703 DP - 1994 Feb 01 TA - The Journal of Experimental Medicine PG - 703--708 VI - 179 IP - 2 4099 - http://jem.rupress.org/content/179/2/703.short 4100 - http://jem.rupress.org/content/179/2/703.full SO - J Exp Med1994 Feb 01; 179 AB - Interleukin 5 (IL-5) is the main factor that promotes the terminal differentiation of eosinophil progenitors (as indicated by colony formation assays), and enhances the effector capacity of mature eosinophils. IL-5 is produced by T lymphocytes, CD4-/CD8- and mast cells and recently, messenger (m)RNA of this cytokine has been identified in eosinophils from patients with coeliac disease, asthma, or eosinophilic heart diseases. In this study, IL-5 mRNA and immunoreactive IL-5 protein were detected in tissue and blood eosinophils from patients with eosinophilic cystitis or hypereosinophilic syndromes but not in Crohn's disease. By electron microscopy associated to immunogold staining, immunoreactive IL-5 was identified in eosinophilic granules. After stimulation with IgA-, IgE-, or IgG-immune complexes, blood eosinophils were shown, by immunocytochemistry and by enzyme-linked immunosorbent assay, to secrete IL-5. These observations demonstrate that eosinophils, under physiological stimulation, can release significant amounts of IL-5, which may contribute to local eosinophil recruitment and activation.