title: CD14 expression on Kupffer cells during the course of carbon tetrachloride-mediated liver injury.
abstract: OBJECTIVE
  To investigate the expression of CD14 on Kupffer cells during the course of carbon tetrachloride (CCl(4))-mediated liver injury and its role in the activation of Kupffer cells.
  
  
  METHODS
  Rats were administered CCl(4) twice weekly for up to 8 weeks. Kupffer cells were isolated from normal and CCl(4)-treated rats by the combined 'collagenase-pronase' perfusion method, discontinuous density gradient centrifugation. On the day after isolation, the cells were incubated with RPMI-1640 containing varying doses of lipopolysaccharide (LPS) for 6 h. Supernatants were then collected for measuring the concentration of tumor necrosis factor-alpha (TNF-alpha) by enzyme-linked immunosorbent assay (ELISA). The expression of CD14 mRNA on Kupffer cells were determined by RT-PCR. The plasma concentrations of endotoxin were determined by chromogenic substrate Limulus amebocyte lysate assay.
  
  
  RESULTS
  Basic TNF-alpha production of Kupffer cells isolated from CCl(4)-treated rats at 4 and 6 weeks was significantly higher than that of normal (P < 0.05). Following LPS stimulation the production of TNF-alpha was markedly increased in Kupffer cells from the 2-, 4- and 6-week treatment groups (P < 0.05). Moreover, LPS-induced TNF-alpha production was dose-dependent. CD14 mRNA expression on Kupffer cells isolated from CCl(4)-treated rats was elevated following 2 weeks of CCl(4) administration and the maximum elevation occurred at 6 weeks. Gene expression was decreased in Kupffer cells after 8 weeks of CCl(4) treatment. CCl(4) administration elicited extensive changes in liver morphology, including steatosis, inflammation and necrosis. The plasma concentrations of endotoxin of CCl(4)-treated rats were increased during the time of liver injury.
  
  
  CONCLUSIONS
  Up-regulation of CD14 expression in Kupffer cells during CCl(4)-mediated chronic liver injury indicates cell activation and that they are more sensitive to LPS stimulation. Kupffer cells are critical effector cells in the early stage of liver injury.
authors.affiliation: Institute of Digestive Disease, Renji Hospital, Shanghai Second Medical University, Shanghai, China. dekaiqiu@sh163.net
authors.forename: De Kai
authors.initials: DK
authors.lastname: Qiu
authors.forename: Jing
authors.initials: J
authors.lastname: Hua
authors.forename: Ji Qiang
authors.initials: JQ
authors.lastname: Li
authors.forename: Eng Ling
authors.initials: EL
authors.lastname: Li
mesh_terms: D000818:Animals; D001483:Base Sequence; D002251:Carbon Tetrachloride / Q000633:toxicity*; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D066298:In Vitro Techniques; D007728:Kupffer Cells / Q000187:drug effects* / Q000276:immunology*; D018950:Lipopolysaccharide Receptors / Q000235:genetics*; D008070:Lipopolysaccharides / Q000097:blood / Q000494:pharmacology; D008099:Liver / Q000187:drug effects* / Q000276:immunology* / Q000293:injuries; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D002251:Carbon Tetrachloride