Differential expression and regulation of chemokines JE, KC, and IP-10 gene in primary cultured murine hepatocytes.
Chemokines are a superfamily of structurally related chemoattractant cytokines. JE (monocyte chemoattractant protein-1) and IP-10 (interferon-inducible protein-10) have been detected in the diseased liver. However the in vitro expression is unclear. In this report, we revealed that JE, KC (melanoma growth-stimulating activity gene), and IP-10 mRNAs are not expressed in the normal liver but spontaneously and time-dependently expressed in the primary hepatocytes. The serum-independent gene expression of both JE and KC lasted over 72 h, but that of IP-10 became undetectable 24 h after isolation with collagenase perfusion method. The induction of the genes' expression was not due to LPS contamination but nevertheless was associated with isolation procedure. Actinomycin D blocked their expression. The increase of their transcripts resulted from greater increase in gene transcription and lower mRNA stability. Consistent with c-jun, their mRNA expressions were simultaneously superinduced by cycloheximide (1 microg/ml), suggesting that de novo protein synthesis is involved their transcriptions. Inhibition by pyrrolidine dithiocarbamate (PDTC), a NF-kappaB/c-rel inhibitor, and EMSA imply that NF-kappaB/c-rel is important in their expressions. Of particular interest is that dexamethasone upregulated the spontaneous expression of KC, but suppressed that of JE and IP-10. LPS upregulated the mRNA levels of JE and KC but did not affect that of IP-10. IFN-gamma induced the expression of IP-10; however unlike in macrophages, it did not selectively inhibit that of JE and KC. Our data demonstrated the existence and differential gene expression of JE, KC, and IP-10 in primary cultured hepatocytes, and these are considered to be a reflex of the alteration of hepatocyte cellular physiology during and after isolation.
Wang
H
H
Department of Medical Zoology, Faculty of Medicine, Tottori University, Yonago, Japan.
Gao
X
X
Fukumoto
S
S
Tademoto
S
S
Sato
K
K
Hirai
K
K
D000818:Animals; D018929:Cell Culture Techniques / Q000379:methods; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000235:genetics*; D054360:Chemokine CXCL1; D054357:Chemokine CXCL10; D019743:Chemokines, CXC / Q000235:genetics*; D002630:Chemotactic Factors / Q000235:genetics*; D003513:Cycloheximide / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology*; D006133:Growth Substances / Q000235:genetics*; D036341:Intercellular Signaling Peptides and Proteins; D007700:Kinetics; D008099:Liver / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009687:Nuclear Proteins / Q000378:metabolism; D011112:Polymyxin B / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic
D018932:Chemokine CCL2; D054360:Chemokine CXCL1; D054357:Chemokine CXCL10; D019743:Chemokines, CXC; D002630:Chemotactic Factors; C475895:Cxcl1 protein, mouse; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; D003513:Cycloheximide; D011112:Polymyxin B