title: Clara cell 10-kDa protein gene transfection inhibits NF-κB activity in airway epithelial cells.
abstract: BACKGROUND
  Clara cell 10-kDa protein (CC10) is a multifunctional protein with anti-inflammatory and immunomodulatory effects. Induction of CC10 expression by gene transfection may possess potential therapeutic effect. Nuclear factor κB (NF-κB) plays a key role in the inflammatory processes of airway diseases.
  
  
  RESULTS
  To investigate potential therapeutic effect of CC10 gene transfection in controlling airway inflammation and the underlying intracellular mechanisms, in this study, we constructed CC10 plasmid and transfected it into bronchial epithelial cell line BEAS-2B cells and CC10 knockout mice. In BEAS-2B cells, CC10's effect on interleukin (IL)-1β induced IL-8 expression was explored by means of RT-PCR and ELISA and its effect on NF-κB classical signaling pathway was studied by luciferase reporter, western blot, and immunoprecipitation assay. The effect of endogenous CC10 on IL-1β evoked IL-8 expression was studied by means of nasal explant culture. In mice, CC10's effect on IL-1β induced IL-8 and nuclear p65 expression was examined by immunohistochemistry. First, we found that the CC10 gene transfer could inhibit IL-1β induced IL-8 expression in BEAS-2B cells. Furthermore, we found that CC10 repressed IL-1β induced NF-κB activation by inhibiting the phosphorylation of IκB-α but not IκB kinase-α/β in BEAS-2B cells. Nevertheless, we did not observe a direct interaction between CC10 and p65 subunit in BEAS-2B cells. In nasal explant culture, we found that IL-1β induced IL-8 expression was inversely correlated with CC10 levels in human sinonasal mucosa. In vivo study revealed that CC10 gene transfer could attenuate the increase of IL-8 and nuclear p65 staining in nasal epithelial cells in CC10 knockout mice evoked by IL-1β administration.
  
  
  CONCLUSIONS
  These results indicate that CC10 gene transfer may inhibit airway inflammation through suppressing the activation of NF-κB, which may provide us a new consideration in the therapy of airway inflammation.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
authors.forename: Xiao-Bo
authors.initials: XB
authors.lastname: Long
authors.forename: Shuang
authors.initials: S
authors.lastname: Hu
authors.forename: Nan
authors.initials: N
authors.lastname: Wang
authors.forename: Hong-Tao
authors.initials: HT
authors.lastname: Zhen
authors.forename: Yong-Hua
authors.initials: YH
authors.lastname: Cui
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000328:Adult; D000818:Animals; D001980:Bronchi / Q000166:cytology*; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D004847:Epithelial Cells / Q000378:metabolism*; D005260:Female; D055786:Gene Knockout Techniques; D006801:Humans; D020672:I-kappa B Proteins; D053583:Interleukin-1beta / Q000494:pharmacology; D016209:Interleukin-8 / Q000378:metabolism; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D008875:Middle Aged; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000378:metabolism*; D009297:Nasal Mucosa / Q000187:drug effects / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D011485:Protein Binding / Q000187:drug effects; D021122:Protein Subunits / Q000378:metabolism; D021381:Protein Transport / Q000187:drug effects; D014158:Transcription, Genetic / Q000187:drug effects; D014162:Transfection; D014598:Uteroglobin / Q000235:genetics* / Q000378:metabolism; D055815:Young Adult
chemical_list: D020672:I-kappa B Proteins; D053583:Interleukin-1beta; D016209:Interleukin-8; D016328:NF-kappa B; C000606204:NFKBIA protein, human; C000606205:Nfkbia protein, mouse; D021122:Protein Subunits; C556389:SCGB1A1 protein, human; C556390:Scgb1a1 protein, mouse; D000072000:NF-KappaB Inhibitor alpha; D014598:Uteroglobin