title: IL-8 reduces VCAM-1 secretion of smooth muscle cells by increasing p-ERK expression when 3-D co-cultured with vascular endothelial cells.
abstract: OBJECTIVE
  The goal of this study was to investigate the crosstalk between vascular endothelial cells (ECs) and smooth muscle cells (SMCs) using a three-dimensional (3-D) co-culture model. In addition, the role of IL-8 in this crosstalk was investigated.
  
  
  METHODS
  A 3-D co-culture model was constructed using a Transwell chamber system and type I collagen gel. Human umbilical artery smooth muscle cells (HUASMCs) were suspended in the gel and added to the upper compartment of the Transwell. Human umbilical vein endothelial cells (HUVECs) were then grown on the surface of the gel. The growth of HUASMCs was tested with a CFDA SE cell proliferation kit. IL-8 and other bioactive substances were investigated by ELISA and real-time PCR. The alteration of p-ERK expression related to the change in IL-8 levels was also examined by Western blot analysis.
  
  
  RESULTS
  The proliferation rate of HUASMCs in the 3-D co-culture model was 0.679 ± 0.057. Secretion and transcription of VEGF, t-PA, NO and VCAM-1 in the 3-D co-culture model were different than in single (2-D) culture. When 3-D co-cultured, IL-8 released by HUVECs was significantly increased (2.35 ± 0.16 fold) (P﹤0.05) and the expression of VCAM-1 from HUASMCs was reduced accordingly (0.55±0.09 fold). In addition, increasing or decreasing the level of IL-8 changed the level of p-ERK and VCAM-1 expression. The reduction of VCAM-1, resulting from increased IL-8, could be blocked by the MEK inhibitor, PD98059.
  
  
  CONCLUSIONS
  Crosstalk between HUVECs and HUASMCs occurred and was probably mediated by IL-8 in this 3-D co-culture model.
authors.affiliation: Shanghai First People’s Hospital, Shanghai Jiao Tong University School of Medicine, PR China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Zhang
authors.forename: Guang
authors.initials: G
authors.lastname: Chu
authors.forename: Hong-Xian
authors.initials: HX
authors.lastname: Wu
authors.forename: Ni
authors.initials: N
authors.lastname: Zou
authors.forename: Bao-Gui
authors.initials: BG
authors.lastname: Sun
authors.forename: Qiu-Yan
authors.initials: QY
authors.lastname: Dai
mesh_terms: D015153:Blotting, Western; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D048049:Extracellular Signal-Regulated MAP Kinases / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007150:Immunohistochemistry; D016209:Interleukin-8 / Q000494:pharmacology*; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D010959:Tissue Plasminogen Activator / Q000235:genetics / Q000378:metabolism; D014471:Umbilical Veins / Q000166:cytology*; D019010:Vascular Cell Adhesion Molecule-1 / Q000235:genetics / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism
chemical_list: D016209:Interleukin-8; D019010:Vascular Cell Adhesion Molecule-1; D042461:Vascular Endothelial Growth Factor A; D048049:Extracellular Signal-Regulated MAP Kinases; D010959:Tissue Plasminogen Activator