title: Mesenchymal stem cells participating in ex vivo endothelium repair and its effect on vascular smooth muscle cells growth.
abstract: BACKGROUND
  Previous studies have shown that mesenchymal stem cells (MSCs) transplantation can promote neovascularization and regenerate damaged myocardium. However, it remains unknown whether MSCs seeding can be used to repair injured cellular components in vascular diseases. In this study we explored the feasibility of applying MSCs to endothelium repair in endothelial damage and vasoproliferative disorders.
  
  
  METHODS
  Ex vivo model of endothelium repair was developed in which rabbit vascular smooth muscle cells (SMCs) were inoculated into the upper chamber and rabbit endothelial cells (ECs)/human MSCs into the lower chamber of a co-culture system. 3H-TdR incorporation and PCNA protein expression were assayed and migrated number of SMCs was calculated to evaluate the effect of MSCs seeding on SMCs growth. Flk-1 and vWF protein expressions were observed to analyze the plasticity of the seeded MSCs along endothelial lineage.
  
  
  RESULTS
  In this co-culture system, no vWF protein but Flk-1 protein was observed in the 25.71% of MSCs after having been co-cultured with mature rabbit ECs for 5 days. Compared with the control group, the proliferation and migration of SMCs was significantly increased by proliferative ECs but decreased by confluent ECs (n=6, P<0.01). MSCs seeding decreased the proliferation and migration of SMCs compatible with the effect of proliferative ECs (n=6, P<0.001). However, no inhibition on SMCs growth was observed with MSCs seeding in comparison to the effect of confluent ECs.
  
  
  CONCLUSIONS
  MSCs seeding can inhibit the proliferation and migration of SMCs. MSCs co-cultured with mature ECs have the ability to undergo milieu-dependent differentiation toward ECs.
authors.affiliation: The Cardiovascular Center, Xin Qiao Hospital, Chongqing 400037, PR China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Wu
authors.forename: Lan
authors.initials: L
authors.lastname: Huang
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhou
authors.forename: Yaoming
authors.initials: Y
authors.lastname: Song
authors.forename: Aimin
authors.initials: A
authors.lastname: Li
authors.forename: Jun
authors.initials: J
authors.lastname: Jin
authors.forename: Bin
authors.initials: B
authors.lastname: Cui
mesh_terms: D000818:Animals; D002455:Cell Division; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology*; D005240:Feasibility Studies; D006801:Humans; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D011817:Rabbits