Kinetics of IL-10 production after segmental antigen challenge of atopic asthmatic subjects

• Published in: Journal of allergy and clinical immunology 2000-11, Vol.106 (5), p.880-886
• Main Authors: Colavita, Annette M., Hastie, Annette T., Musani, Ali I., Pascual, Rodolfo M., Reinach, Alan J., Lustine, H.Todd, Galati, Steve A., Zangrilli, James G., Fish, James E., Peters, Stephen P.
• Format: Article
• Language: English
• Subjects: Allergens - immunology; allergic asthma; Allergic diseases; Anti-Inflammatory Agents - pharmacology; Antigens, Plant; Asthma - immunology; Biological and medical sciences; bronchoalveolar lavage; Bronchoalveolar Lavage Fluid - cytology; Bronchoalveolar Lavage Fluid - immunology; Cells, Cultured; cytokines; Dexamethasone - pharmacology; eosinophils; Eosinophils - cytology; Eosinophils - immunology; glucocorticoids; Glucocorticoids - pharmacology; Humans; immunocytochemistry; Immunopathology; Interleukin-10; Interleukin-10 - biosynthesis; Kinetics; macrophages; Macrophages - cytology; Macrophages - drug effects; Macrophages - immunology; Medical sciences; Plant Proteins - immunology; Poaceae - immunology; Pollen - immunology; Respiratory and ent allergic diseases; segmental antigen challenge
• ISSN: 0091-6749; 1097-6825
• DOI: 10.1067/mai.2000.110475

Background: IL-10 is an anti-inflammatory cytokine made by lymphocytes, monocytes-macrophages, and eosinophils, and it may have an important role in regulating the asthmatic inflammatory response. IL-10 levels have been reported to be reduced in asthmatic airways, potentially contributing to more intense inflammation. Objective: We sought to determine whether IL-10 levels were deficient in patients with mild asthma compared with controls and to determine whether IL-10 levels were associated with the resolution of eosinophilic inflammation. Methods: We quantified IL-10 levels in the bronchoalveolar lavage (BAL) fluid (ELISA), BAL cells (quantitative immunocytochemistry), purified alveolar macrophages-monocytes studied ex vivo (ELISA), before (day 1) and after (24 hours [day 2], 1 week [day 9], and 2 weeks [day 16]) segmental antigen challenge (SAC), and investigated the effect of glucocorticoid treatment on ex vivo macrophage-monocyte IL-10 production. Results: IL-10 levels were significantly higher in the BAL fluid of mild asthmatic subjects who demonstrated a dual reaction (both early and late) after whole lung ragweed inhalation challenge compared with nonallergic, nonasthmatic control subjects before and 24 hours and 1 week after SAC. Macro-phages-monocytes obtained before and after SAC from asthmatic patients also secreted increased amounts of IL-10 ex vivo than those from controls. Dexamethasone did not significantly change spontaneous IL-10 secretion from macrophages-monocytes in vitro. Quantitative immunocytochemical analysis of BAL cells demonstrated increased IL-10 in macrophages 24 hours after SAC and a similar trend in eosinophils. Conclusion: IL-10 is not deficient in mild asthma. Furthermore, BAL IL-10 levels are significantly higher in asthmatic subjects with a dual response than in control subjects before and after SAC. The increase in IL-10 was coincident with the initial increase in BAL eosinophils, although BAL eosinophilia persisted after IL-10 levels had returned to baseline, suggesting that the increased IL-10 levels could not promptly terminate this localized eosinophilic response. (J Allergy Clin Immunol 2000;106:880-6.)