title: Synergy of IL-27 and TNF-α in regulating CXCL10 expression in lung fibroblasts.
abstract: IL-27 is involved in inflammatory reactions. CXCL10 is an important chemokine contributing to airway inflammatory disease. In this study, we investigated whether IL-27 modulated the synthesis of CXCL10 in primary human lung fibroblasts (HLFs). HLFs were activated by IL-27 alone, or in combination with other cytokines. CXCL10 synthesis was measured by real-time PCR and ELISA. An examination of transcriptional regulation was performed via the transient transfection of promoter constructs, whereas mRNA stability was assessed by actinomycin D chase and real-time PCR. The underlying signaling pathways were studied by Western blotting and intracellular staining, using flow cytometry. Our results demonstrated that IL-27 induced and synergized with TNF-α to up-regulate CXCL10 mRNA and protein concentrations in a steroid-insensitive manner. This synergistic CXCL10 production was dependent on the transcriptional regulation of CXCL10 gene promoter activity and the enhanced stability of CXCL10 mRNA because of IL-27 and TNF-α, and this synergism was regulated by the activation of p38 mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-OH kinase (PI3K)-Akt dominantly, and in small part via NF-κB. Interestingly, IL-27 promoted the basal and enhanced TNF-α-induced phosphorylation of p38 MAPK and Akt, but not IκBα. Moreover, enhanced CXCL10 mRNA stability occurred via a p38 MAPK-dependent pathway. Finally, clinical analysis showed that IL-27 was detected in the bronchoalveolar lavage of patients with asthma, chronic obstructive pulmonary disease (COPD), and pulmonary tuberculosis (PTB), and increased IL-27 concentrations were correlated with increased CXCL10 concentrations in patients with COPD and PTB. Our findings suggest that IL-27 has the potential to amplify airway inflammation via the induction of CXCL10 from HLFs, in combination with TNF-α.
authors: Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors: Shanshan
authors: S
authors: Dong
authors: Xuemei
authors: X
authors: Zhang
authors: Yujuan
authors: Y
authors: He
authors: Fang
authors: F
authors: Xu
authors: Dairong
authors: D
authors: Li
authors: WenChun
authors: W
authors: Xu
authors: Hong
authors: H
authors: Wang
authors: Yibing
authors: Y
authors: Yin
authors: Ju
authors: J
authors: Cao
mesh_terms: D018893:Bronchoalveolar Lavage; D002478:Cells, Cultured; D054357:Chemokine CXCL10 / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D005347:Fibroblasts / Q000378:metabolism* / Q000473:pathology; D005786:Gene Expression Regulation; D006801:Humans; D020672:I-kappa B Proteins / Q000235:genetics / Q000378:metabolism; D007378:Interleukins / Q000235:genetics / Q000378:metabolism*; D008168:Lung / Q000378:metabolism* / Q000473:pathology; D008171:Lung Diseases / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D020935:MAP Kinase Signaling System / Q000235:genetics; D008297:Male; D000072000:NF-KappaB Inhibitor alpha; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation / Q000235:genetics; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism*; D048051:p38 Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism
chemical_list: D054357:Chemokine CXCL10; D020672:I-kappa B Proteins; D007378:Interleukins; D000072000:NF-KappaB Inhibitor alpha; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D014409:Tumor Necrosis Factor-alpha; D048051:p38 Mitogen-Activated Protein Kinases; C114753:CXCL10 protein, human; C464565:MYDGF protein, human; C000606204:NFKBIA protein, human