title: Lipopolysaccharide upregulates the expression of Toll-like receptor 4 in human vascular endothelial cells.
abstract: OBJECTIVE
  To investigate the expression of Toll-like receptor 2 (TLR2) and Toll-like receptor 4 (TLR4) and the effect of lipopolysaccharide (LPS) on their expression in cultured endothelial cells.
  
  
  METHODS
  Total RNA was extracted from ECV304 cells and isolated human umbilical vein endothelial cells (HUVECs) exposed to LPS, respectively. The quantification of TLR2 and TLR4 mRNA in HUVECs and EVC304 cells was carried out by reverse transcriptase-polymerase chain reaction (RT-PCR).
  
  
  RESULTS
  ECV304 cells and HUVECs were able to express TLR2 and TLR4 mRNA, but the expression levels of TLR4 appeared to be stronger than those of TLR2. LPS could upregulate the expression levels of TLR4 obviously, whereas it had no effect on the expression level of TLR2.
  
  
  CONCLUSIONS
  Our data indicate that TLR4 may be the LPS signal transducer in endothelial cells and plays important roles in the cell activation of LPS. The ECV304 cell line is a better experimental model than isolated HUVECs in the research of endothelial cells.
authors.affiliation: Department Four, Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing 400042, China.
authors.forename: Qingwu
authors.initials: Q
authors.lastname: Yang
authors.forename: Peifang
authors.initials: P
authors.lastname: Zhu
authors.forename: Zhengguo
authors.initials: Z
authors.lastname: Wang
authors.forename: Jianxin
authors.initials: J
authors.lastname: Jiang
mesh_terms: D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D029721:Drosophila Proteins; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008562:Membrane Glycoproteins / Q000235:genetics*; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics*; D013997:Time Factors; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors; D014471:Umbilical Veins / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D029721:Drosophila Proteins; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C495342:TLR2 protein, human; C495345:TLR4 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors