title: [The expression and role of Toll receptor 4 in renal tubular epithelial cells in hepatitis B virus infection].
abstract: OBJECTIVE
  To explore the expression and role of Toll receptor 4 (TLR4) in human proximal tubular epithelial cell line HK-2, infected by HBV.
  
  
  METHODS
  The serum of HBV DNA copies between 10(7) - 10(8)/ml was collected. Before and after infected by HBV DNA positive serum, the HK-2 cells' morphology and the expression of α-smooth muscle actin (α-SMA) were observed by microscopy and immunofluorescence, and the effects of different concentrations of lipopolysaccharides (LPS, TLR4-stimulating factor) and CLI-095 (TLR4 Inhibitor) on the proliferation rate of HK-2 cells were observed by MTT assays. After HBV serum and 10 µg/ml LPS and 5 µl/ml CLI-095 acted on HK-2 cells, TLR4 protein expression was measured by immunofluorescence and Western-blotting assay, and HBsAg and HBeAg in cell culture medium were detected by ELISA, and HBV DNA copies by fluorescence quantitative PCR.
  
  
  RESULTS
  The longer HBV infected HK-2 cells, the more irregular of the cells' shape, the fewer number of the cells were left. But compared with HBV infected after 24 hours, α-SMA was more expressed after HBV infected 12 hours.After infected by HBV serum in 24 hours, HK-2 cells' proliferation rate was positively correlation in a dose range of LPS, but was negatively correlated with the CLI-095 (P < 0.05). The levels of HBsAg and HBeAg in cell culture medium were largest when the LPS concentration was at 10 µg/ml and CLI-095 at 5 µg/ml. The expression of TLR4 significantly increased in HK-2 cells treated with LPS compared with those with CLI-095, but HBV DNA levels and HBsAg and HBeAg expression levels were lower.
  
  
  CONCLUSIONS
  HBV infection may promote cell transdifferentiation and cell injury. The stimulation of HK-2 infected with HBV by LPS may upregulate the expression of TLR4 and reduce the copies of HBV DNA.
authors.affiliation: Department of Nephrology, the Affiliated First People's Hospital, Shanghai Jiaotong University, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhu
authors.forename: Wei-Jie
authors.initials: WJ
authors.lastname: Yuan
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.forename: Yan
authors.initials: Y
authors.lastname: Peng
authors.forename: Li-Jie
authors.initials: LJ
authors.lastname: Gu
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
mesh_terms: D002460:Cell Line; D004847:Epithelial Cells / Q000378:metabolism*; D006509:Hepatitis B / Q000378:metabolism*; D006515:Hepatitis B virus / Q000472:pathogenicity; D006801:Humans; D007687:Kidney Tubules, Proximal / Q000378:metabolism*; D051197:Toll-Like Receptor 4 / Q000378:metabolism*
chemical_list: C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4