title: [Effects of cryopreservation length on the proliferative potential of cord blood hematopoietic cells in vitro].
abstract: OBJECTIVE
  To study the effects of cryopreservation length on the proliferative potential of hematopoietic cells derived from cord blood.
  
  
  METHODS
  Using Dextran-40 and 10% DMSO as cryoprotectants, separated nuclear cells were stored in liquid nitrogen after they were freezed according programme. One month or 4 months later, they were thawed and expanded in serum-free medium for culture and expansion of hematopoietic cell (SFEM) for 5 weeks. Dynamic results were detected every week.
  
  
  RESULTS
  At the 5th week of expanding, TNC were expanded for 1499.0 +/- 115.6-folds and 1513.0 +/- 110.4-folds, respectively. CD34+ cells and CFCs reached to their highest level at the 2nd week and at the 3rd week. CD34+ cells were expanded for 63.8 +/- 6.1-folds and 62.4 +/- 5.7-folds, respectively. CFCs were expanded for 53.8 +/- 6.3-folds and 54.8 +/- 6.7-folds, respectively. Between the two kinds of cells, statistical significant difference in proliferative potential wasn't detected.
  
  
  CONCLUSIONS
  In ideal cryopreservative condition, the cryopreservation length would do not affect the proliferative potential of cord blood hematopoietic cells.
authors.affiliation: Cord Blood Bank Affiliated to Shenzhen Baoan Blood Center, Shenzhen 518101, China.
authors.forename: Mei-Ling
authors.initials: ML
authors.lastname: Zhu
authors.forename: Ru-Guang
authors.initials: RG
authors.lastname: Chen
authors.forename: Yong-Zhi
authors.initials: YZ
authors.lastname: Xi
authors.forename: Yong-Mei
authors.initials: YM
authors.lastname: Liu
authors.forename: Li-Zhen
authors.initials: LZ
authors.lastname: Peng
mesh_terms: D049109:Cell Proliferation; D002470:Cell Survival; D002478:Cells, Cultured; D015925:Cryopreservation / Q000379:methods*; D005312:Fetal Blood / Q000166:cytology*; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D013997:Time Factors