title: Conditions to improve expansion of human mesenchymal stem cells based on rat samples.
abstract: OBJECTIVE
  To improve the isolation and expansion of human marrow-derived mesenchymal stem cells (MSCs) based on rat samples.
  
  
  METHODS
  Based on the fact that rat MSCs are relatively easy to obtain from a small aspirate, bone marrow-derived MSCs from rat were cultured and characterized to set up the different protocols used in this study. Then, accordingly, almost the same protocols were performed on human healthy bone marrow samples, after obtaining approval of the ethics committee and gaining informed consent. We used different protocols and culture conditions, including the type of basal media and the culture composition. The MSCs were characterized by immunophenotyping and differentiation.
  
  
  RESULTS
  There was no difference in morphology and proliferation capacity between different culture media at the first passage. During the 5-7th passages, the cells gradually lost their morphology and proliferation potential on Dulbecco's modified Eagle's medium (DMEM) high glucose and α modified Eagle's medium. Although the cells expanded rapidly for up to 10 passages on DMEM low glucose containing 10% to 15% fetal calf serum (FCS), their proliferation was arrested without change in morphology and differentiation capacity at the third passage on 5% FCS. Flow cytometric analysis and functional tests confirmed that more than 90% of marrow cells which were isolated and expanded by our selective protocols were MSCs.
  
  
  CONCLUSIONS
  We improved the isolation and expansion of human bone marrow derived MSCs, based on rat sample experiments, for further experimental and clinical use.
authors.affiliation: Maryam Ayatollahi, Transplant Research Center, Stem Cells and Transgenic Technology Research Center, Nemazi Hospital, Shiraz University of Medical Sciences, Shiraz 7193711351, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Ayatollahi
authors.forename: Maryam Kabir
authors.initials: MK
authors.lastname: Salmani
authors.forename: Bita
authors.initials: B
authors.lastname: Geramizadeh
authors.forename: Seyed Ziaadin
authors.initials: SZ
authors.lastname: Tabei
authors.forename: Masoud
authors.initials: M
authors.lastname: Soleimani
authors.forename: Mohammad Hosein
authors.initials: MH
authors.lastname: Sanati