title: Transforming growth factor-beta increases the expression of vascular smooth muscle cell markers in human multi-lineage progenitor cells.
abstract: BACKGROUND
  Vascular smooth muscle cell (SMC) differentiation is an essential component of vascular repair and tissue engineering. However, currently used cell models for the study of SMC differentiation have several limitations. Multi-lineage progenitor cells (MLPCs) originate from human umbilical cord blood and are cloned from a single cell. The object of this study was to investigate whether MLPCs could differentiate into SMCs in vitro with induction by transforming growth factor beta1 (TGF-beta1).
  
  
  METHODS
  MLPCs were treated without or with TGF-beta1 (1 and 5 ng/mL) in mesenchymal stem cell media plus 1% FBS for 7 days. Total RNA was isolated from the MLPCs, and semi-quantitative real-time PCR was performed to test the following mRNA levels: early and late phase SMC-specific markers, two endothelial cell (EC)-specific markers, endothelial progenitor cell (EPC) marker CD34, TGF-beta1 accessory protein CD105, and adhesion molecule CD146.
  
  
  RESULTS
  TGF-beta1 (1 ng/mL) significantly increased the mRNA levels of SMC-specific markers SM22α, calponin-1, SM α-actin, caldesmon, tropomyosin and MLCK as well as adhesion molecule CD146. The mRNA levels of EC-specific markers VE-cadherin and VEGFR-2, EPC marker CD34 and TGF-beta1 accessory protein CD105 were decreased significantly, after MLPC were treated with TGF-beta1 (1 ng/mL). TGF-beta1 at 5 ng/mL showed similar effect on the expression of these genes.
  
  
  CONCLUSIONS
  This study demonstrates that in the presence of TGF-beta1, MLPCs undergo SMC lineage differentiation indicating that MLPCs are a promising cell model for SMC lineage differentiation studies, which may contribute to advances in vascular repair and tissue engineering.
authors.affiliation: Division of Vascular Surgery and Endovascular Therapy, Michael E DeBakey Department of Surgery, Baylor College of Medicine, Molecular Surgeon Research Center, Houston, TX, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Yang
authors.forename: Lidong
authors.initials: L
authors.lastname: Zhang
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Weakley
authors.forename: Peter H
authors.initials: PH
authors.lastname: Lin
authors.forename: Qizhi
authors.initials: Q
authors.lastname: Yao
authors.forename: Changyi
authors.initials: C
authors.lastname: Chen
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D051929:CD146 Antigen / Q000235:genetics / Q000378:metabolism; D019070:Cell Lineage / Q000187:drug effects*; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D032389:Myocytes, Smooth Muscle / Q000187:drug effects / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013234:Stem Cells / Q000187:drug effects / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
chemical_list: D015415:Biomarkers; D051929:CD146 Antigen; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta