title: NF-κB plays a key role in inducing CD274 expression in human monocytes after lipopolysaccharide treatment.
abstract: CD274, one of two co-stimulatory ligands for programmed death 1 and widely expressed in the mononuclear phagocyte system (MPS), may co-stimulate T cells and regulates inflammatory responses. However, changes in CD274 gene expression and the underlying molecular mechanism are poorly understood during inflammatory responses. Therefore, delineation of the complex mechanisms regulating CD274 expression is critical to understand this immunoregulatory system during inflammatory responses. The purpose of this study was to assess the molecular mechanisms regulating CD274 expression in an in vitro monocyte model of inflammatory response. Firstly, CD274 expression levels in human primary monocytes after lipopolysaccharide (LPS) treatment were observed and correlated with NF-κB activation. Secondly, based on the distribution of putative NF-κB binding sites, 5' truncated human CD274 promoter reporters were constructed, transfected into U937 cells and critical promoter regions for basal (nt -570 to +94) and LPS-induced (nt -1735 to -570) transcription were identified by dual luciferase assays. Finally, a key NF-κB binding site (nt -610 to -601) for LPS-inducible CD274 transcriptional activity was characterized by point mutation analysis and chromatin immunoprecipitation analysis assays (ChIP). Thus, the present study establishes a molecular basis to understand the mechanisms governing CD274 expression in certain infections and inflammatory disorders.
authors.affiliation: Department of Medical Genetics, Third Military Medical University, Chongqing, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Huang
authors.forename: Qianjun
authors.initials: Q
authors.lastname: Wen
authors.forename: Yongliang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Qiangguo
authors.initials: Q
authors.lastname: Gao
authors.forename: Yun
authors.initials: Y
authors.lastname: Bai
mesh_terms: D060890:B7-H1 Antigen / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D002460:Cell Line; D005786:Gene Expression Regulation / Q000187:drug effects*; D017930:Genes, Reporter; D006801:Humans; D007249:Inflammation; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008156:Luciferases; D008969:Molecular Sequence Data; D009000:Monocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D016328:NF-kappa B / Q000235:genetics* / Q000276:immunology; D011401:Promoter Regions, Genetic; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D060890:B7-H1 Antigen; C423236:CD274 protein, human; D008070:Lipopolysaccharides; D016328:NF-kappa B; D008156:Luciferases