title: EphrinB2 Stabilizes Vascularlike Structures Generated by Endothelial Cells and Stem Cells from Apical Papilla.
abstract: BACKGROUND
  This study aimed to investigate the roles of ephrinB2 in stabilizing vascularlike structures generated by stem cells from apical papilla (SCAPs) and human umbilical vein endothelial cells (HUVECs).
  
  
  METHODS
  HUVECs were seeded alone or with SCAPs concurrently or 12 hours later. Angiogenesis and ephrinB2 phosphorylation were assayed at different time points. Additionally, ephrinB2 expression in SCAPs and HUVECs was silenced with small interfering RNA, and vascularlike structure formation within coculture was assessed; 1 × 10(5) HUVECs were seeded in transwell inserts, and 6 × 10(5) SCAPs were plated in lower wells with or without ephrinB2-Fc. Migratory cells were stained and counted. Delayed addition of ephrinB2-Fc to the coculture of HUVECs and SCAPs was performed to evaluate the role of ephrinB2 on the stabilization of vascularlike structures.
  
  
  RESULTS
  Concurrent coculture of SCAPs and HUVECs yielded significantly longer tubule lengths at 4, 8, and 12 hours (P < .05). Delayed addition of SCAPs to coculture with HUVECs resulted in vascularlike structures persisting longer than the HUVEC monoculture. Western blot confirmed that ephrinB2 phosphorylation was initiated at 0.5 hours of coculture and peaked at 1 hour. Silencing ephrinB2 expression in SCAPs and HUVECs resulted in the absence of vascularlike structures. Enhanced migration of HUVECs by SCAPs could be inhibited by ephrinB2-Fc. When ephrinB2-Fc was added at 3 hours of coculture, the vascularlike structures were stabilized for more than 12 hours as compared with 9 hours in the control group.
  
  
  CONCLUSIONS
  EphrinB2 plays an important role in the stabilization of vascularlike structures generated by HUVECs and SCAPs.
authors.affiliation: Comprehensive Dental Care, Endodontics, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Changyong
authors.initials: C
authors.lastname: Yuan
authors.affiliation: Dental Implant Center, Xuzhou Stomatological Hospital, Xuzhou, China.
authors.forename: Penglai
authors.initials: P
authors.lastname: Wang
authors.affiliation: Comprehensive Dental Care, Endodontics, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China; Dental Implant Center, Xuzhou Stomatological Hospital, Xuzhou, China.
authors.forename: Shaoyue
authors.initials: S
authors.lastname: Zhu
authors.affiliation: Comprehensive Dental Care, Endodontics, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Zou
authors.affiliation: Comprehensive Dental Care, Endodontics, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Wang
authors.affiliation: Comprehensive Dental Care, Endodontics, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Jianguang
authors.initials: J
authors.lastname: Xu
authors.affiliation: Comprehensive Dental Care, Endodontics, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Boon Chin
authors.initials: BC
authors.lastname: Heng
authors.affiliation: Department of Endodontics, University of Texas Health Science Center at San Antonio, San Antonio, Texas.
authors.forename: Anibal
authors.initials: A
authors.lastname: Diogenes
authors.affiliation: Comprehensive Dental Care, Endodontics, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China. Electronic address: zhangcf@hku.hk.
authors.forename: Chengfei
authors.initials: C
authors.lastname: Zhang
mesh_terms: D003771:Dental Papilla / Q000098:blood supply / Q000502:physiology*; D042783:Endothelial Cells / Q000502:physiology*; D004797:Enzyme-Linked Immunosorbent Assay; D036388:Ephrin-B2 / Q000502:physiology*; D006801:Humans; D018919:Neovascularization, Physiologic / Q000502:physiology; D060888:Real-Time Polymerase Chain Reaction; D013234:Stem Cells / Q000502:physiology*; D019227:Tooth Apex / Q000098:blood supply / Q000502:physiology*; D014471:Umbilical Veins / Q000166:cytology
chemical_list: D036388:Ephrin-B2
keywords: Angiogenesis; ephrinB2; human umbilical vein endothelial cells; stem cells from apical papilla