BACKGROUND: IL-17A and IL-19 are highly expressed in chronic inflammatory diseases, such as psoriasis and asthma. IL-19 plays a significant role in the enhancement of T(H)2 cytokine secretion in allergic diseases, but its cellular source in asthmatic patients remains unknown. OBJECTIVE: Our aims were to determine whether the epithelium is a major source of airway mucosal IL-19 and to elucidate the mechanism of gene expression regulation. METHODS: Immunofluorescent staining was used to determine IL-19 protein expression in tracheal tissue sections of various airway diseases. Well-differentiated primary human bronchial epithelial cultures and a corresponding cell line were used as in vitro models to study gene regulation. RESULTS: We found significantly higher IL-19 expression in airway epithelia of asthmatic patients than in epithelia of patients with other diseases. Using a cytokine panel, we demonstrated the upregulation of IL-19 expression in cultures by two T(H)2 cytokines, IL-4 and IL-13, in addition to the previously found T(H)17 cytokine IL-17A. Moreover, cotreatment of IL-17A and IL-4/IL-13 synergistically upregulated IL-19 expression. Using siRNA and chemical inhibitor approaches, we demonstrated a transcriptional regulation of IL-19 by nuclear factor kappaB and signal transducer and activator of transcription (STAT) 6. The addition of IL-13 to IL-17A stimulation triggers a shift from nuclear factor kappaB-dependent transcriptional regulation to one that is STAT6 based. Using chromatin immunoprecipitation assays, we demonstrated the presence of STAT6-binding elements in the IL-19 promoter region. CONCLUSION: We propose that an IL-17A- and IL-13-induced synergism in IL-19 stimulation in airway epithelia occurs through a STAT6-dependent pathway.
BACKGROUND:IL-17A and IL-19 are highly expressed in chronic inflammatory diseases, such as psoriasis and asthma. IL-19 plays a significant role in the enhancement of T(H)2 cytokine secretion in allergic diseases, but its cellular source in asthmatic patients remains unknown. OBJECTIVE: Our aims were to determine whether the epithelium is a major source of airway mucosal IL-19 and to elucidate the mechanism of gene expression regulation. METHODS: Immunofluorescent staining was used to determine IL-19 protein expression in tracheal tissue sections of various airway diseases. Well-differentiated primary human bronchial epithelial cultures and a corresponding cell line were used as in vitro models to study gene regulation. RESULTS: We found significantly higher IL-19 expression in airway epithelia of asthmatic patients than in epithelia of patients with other diseases. Using a cytokine panel, we demonstrated the upregulation of IL-19 expression in cultures by two T(H)2 cytokines, IL-4 and IL-13, in addition to the previously found T(H)17 cytokine IL-17A. Moreover, cotreatment of IL-17A and IL-4/IL-13 synergistically upregulated IL-19 expression. Using siRNA and chemical inhibitor approaches, we demonstrated a transcriptional regulation of IL-19 by nuclear factor kappaB and signal transducer and activator of transcription (STAT) 6. The addition of IL-13 to IL-17A stimulation triggers a shift from nuclear factor kappaB-dependent transcriptional regulation to one that is STAT6 based. Using chromatin immunoprecipitation assays, we demonstrated the presence of STAT6-binding elements in the IL-19 promoter region. CONCLUSION: We propose that an IL-17A- and IL-13-induced synergism in IL-19 stimulation in airway epithelia occurs through a STAT6-dependent pathway.
Authors: S Molet; Q Hamid; F Davoine; E Nutku; R Taha; N Pagé; R Olivenstein; J Elias; J Chakir Journal: J Allergy Clin Immunol Date: 2001-09 Impact factor: 10.793
Authors: M Humbert; S R Durham; P Kimmitt; N Powell; B Assoufi; R Pfister; G Menz; A B Kay; C J Corrigan Journal: J Allergy Clin Immunol Date: 1997-05 Impact factor: 10.793
Authors: Sara L Hall; Theresa Baker; Stephane Lajoie; Phoebe K Richgels; Yanfen Yang; Jaclyn W McAlees; Adelaide van Lier; Marsha Wills-Karp; Umasundari Sivaprasad; Thomas H Acciani; Timothy D LeCras; Jocelyn Biagini Myers; Melinda Butsch Kovacic; Ian P Lewkowich Journal: J Allergy Clin Immunol Date: 2016-06-11 Impact factor: 10.793
Authors: Michelle L Manni; Sivanarayana Mandalapu; Kevin J McHugh; M Merle Elloso; Paul L Dudas; John F Alcorn Journal: J Immunol Date: 2016-01-04 Impact factor: 5.422