title: Long-term proliferation and characterization of human spermatogonial stem cells obtained from obstructive and non-obstructive azoospermia under exogenous feeder-free culture conditions.
abstract: OBJECTIVE
  The aim of the present study was to improve efficiency of isolation and to optimize proliferative potential of human spermatogonial stem cells (SSCs) obtained from obstructive azoospermic (OA) and non-obstructive azoospermic (NOA) patients, and further, to characterize these cells for potential use in infertility treatment or study of reproductive biology.
  
  
  METHODS
  We have applied a cell-sorting method, using collagen and magnetic activated cell separation to overcome obstacles, developing a collection system, and simple long-term proliferation system, that yields large numbers of high-purity SSCs from obstructive OA and NOA patients.
  
  
  RESULTS
  SSCs derived from OA and NOA patients proliferated and maintained their characteristics for more than 12 passages (>6 months) in vitro. Moreover, the population of cells positive for the SSC-specific markers GFRalpha-1 and integrin alpha6, increased to more than 80% at passage 8.
  
  
  CONCLUSIONS
  These finding may support the idea that in vitro propagation of SSCs could be a useful tool for infertility treatment and study of reproductive biology.
authors.affiliation: Fertility Center, CHA Gangnam Medical Center, CHA University, Seoul, Korea.
authors.forename: J J
authors.initials: JJ
authors.lastname: Lim
authors.forename: S-Y
authors.initials: SY
authors.lastname: Sung
authors.forename: H J
authors.initials: HJ
authors.lastname: Kim
authors.forename: S-H
authors.initials: SH
authors.lastname: Song
authors.forename: J Y
authors.initials: JY
authors.lastname: Hong
authors.forename: T K
authors.initials: TK
authors.lastname: Yoon
authors.forename: J K
authors.initials: JK
authors.lastname: Kim
authors.forename: K-S
authors.initials: KS
authors.lastname: Kim
authors.forename: D R
authors.initials: DR
authors.lastname: Lee
mesh_terms: D053713:Azoospermia; D002469:Cell Separation; D006801:Humans; D008297:Male; D012106:Research; D013093:Spermatogonia / Q000166:cytology*; D013234:Stem Cells / Q000166:cytology*