IL-9-mediated induction of eotaxin1/CCL11 in human airway smooth muscle cells.
Recent work has shown the potential importance of IL-9 in allergic diseases. The development of transgenic mice overexpressing IL-9 has suggested a key role for this cytokine in the development of the asthmatic phenotype including airway eosinophilia. In this study, we evaluated the expression of the IL-9R and the effects of IL-9 on human ASM cells by examining the release of Th2-associated chemokines (eotaxin1/CCL11 and thymus- and activation-regulated chemokine (TARC)/CCL17). IL-9R alpha-chain mRNA and surface expression were detected in cultured human airway smooth muscle (ASM) cells. In addition, primary cultured ASM cells, as well as bronchial smooth muscle cells within biopsies of asthmatics and not control subjects, revealed IL-9R protein expression. IL-9 stimulation of human ASM cells resulted in release of eotaxin1/CCL11, but had no effect on the release of TARC/CCL17, in time- and dose-dependent manner. Moreover, in vitro chemotaxis assay demonstrated that conditioned medium from IL-9-stimulated ASM cells attracted human eosinophils. Neutralizing Abs to IL-9, but not to IL-4 or IL-13, reduced significantly IL-9-induced production of eotaxin1/CCL11 from ASM cells. Interestingly, real-time RT-PCR showed that IL-9 up-regulated eotaxin1/CCL11 mRNA expression, but had no effect on TARC/CCL17. Treatment with Act D abrogates IL-9-induced eotaxin1/CCL11 mRNA and protein release by ASM cells. Finally, transfection study using eotaxin1/CCL11 promoter luciferase construct confirmed that IL-9 induced eotaxin1/CCL11 at the transcriptional level. Taken together, these data provide new evidence demonstrating that IL-9-dependent activation of ASM cells contributes to eosinophilic inflammation observed in asthma.
Gounni
Abdelilah Soussi
AS
Department of Immunology, University of Manitoba, Winnipeg, Manitoba, Canada. gounni@cc.umanitoba.ca
Hamid
Qutayba
Q
Rahman
Sahidur M
SM
Hoeck
Jutta
J
Yang
Jie
J
Shan
Lianyu
L
D001249:Asthma / Q000276:immunology / Q000503:physiopathology; D001980:Bronchi / Q000276:immunology / Q000378:metabolism*; D054413:Chemokine CCL11; D054414:Chemokine CCL17; D019742:Chemokines, CC / Q000276:immunology / Q000378:metabolism*; D002634:Chemotaxis, Leukocyte / Q000276:immunology; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D018922:HL-60 Cells; D006801:Humans; D016906:Interleukin-9 / Q000276:immunology / Q000494:pharmacology*; D032389:Myocytes, Smooth Muscle / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D018123:Receptors, Interleukin / Q000096:biosynthesis* / Q000187:drug effects / Q000276:immunology; D053651:Receptors, Interleukin-9; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014162:Transfection
C515456:CCL11 protein, human; C106230:CCL17 protein, human; D054413:Chemokine CCL11; D054414:Chemokine CCL17; D019742:Chemokines, CC; C508045:IL9R protein, human; D016906:Interleukin-9; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D053651:Receptors, Interleukin-9