title: A new inducible adenoviral expression system that responds to inflammatory stimuli in vivo.
abstract: BACKGROUND
  Gene transfer using inducible promoters, which control expression of transgenic proteins in response to physiological conditions, may have significant advantages. In this study, we tried to achieve an inducible adenoviral expression system for physiologically responsive gene therapy of autoimmune or inflammatory diseases.
  
  
  METHODS
  A luciferase reporter vector with a hybrid promoter containing the human IL-1beta enhancer region (-3690 to - 2720) and the human CIITA promoter IV (-399 to + 2) was constructed. A replication-deficient adenovirus was engineered with luciferase controlled by the IL1beta/CIITApIV promoter (Ad-IL1beta/CIITApIV-Luc). The reporter vector or adenovirus was transfected to C57Bl/6 myeloid dendritic cells (DCs), RAW264.7, and Hep G2 to study the in vitro characteristics of this hybrid promoter. An inflammation model was prepared by injecting lipopolysaccharide (LPS) into Balb/c mice intraperitoneally (i.p.), and infected with Ad-IL1beta/CIITApIV-Luc or Ad-CMV-Luc to study the in vivo characteristics of the IL1beta/CIITApIV promoter.
  
  
  RESULTS
  The IL1beta/CIITApIV hybrid promoter has pronounced promoter activity, broad-range responsiveness to cytokines or LPS, and can be rechallenged after first induction. In the inflammation model, IL1beta/CIITApIV could drive hepatic luciferase expression increasedly rapidly after LPS challenge and in a LPS dose-dependent manner.
  
  
  CONCLUSIONS
  Using the IL1beta/CIITApIV hybrid promoter in gene transfer vectors may make it possible to produce transgenic proteins in vivo in direct relationship with the intensity and duration of an individual's status. By providing endogenously controlled production of transgenic proteins, this approach might limit the severity of autoimmune or inflammatory response without interfering with the beneficial components of host defense and immunity.
authors.affiliation: Department of Laboratory Diagnosis, Changhai Hospital, The Second Military Medical University, Shanghai, PR China.
authors.forename: Gang
authors.initials: G
authors.lastname: Cai
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Nie
authors.forename: Pin'e
authors.initials: P
authors.lastname: Guo
authors.forename: Zheng
authors.initials: Z
authors.lastname: Guan
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: Qian
authors.initials: Q
authors.lastname: Shen
mesh_terms: D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D002460:Cell Line; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology; D017930:Genes, Reporter; D005822:Genetic Vectors; D006321:Heart / Q000821:virology; D006801:Humans; D007249:Inflammation / Q000139:chemically induced / Q000235:genetics / Q000628:therapy; D053583:Interleukin-1beta / Q000235:genetics*; D015850:Interleukin-6 / Q000097:blood; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects / Q000201:enzymology / Q000821:virology; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009206:Myocardium / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics*; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins; D015534:Trans-Activators / Q000235:genetics*
chemical_list: C508585:IL1B protein, human; D053583:Interleukin-1beta; D015850:Interleukin-6; D008070:Lipopolysaccharides; C083728:MHC class II transactivator protein; D009687:Nuclear Proteins; D011994:Recombinant Proteins; D015534:Trans-Activators; D008156:Luciferases