title: Detection of a CD4+CD8-CD3- cell subpopulation during the differentiation of cord blood CD34+ cells into T cells in vitro.
abstract: BACKGROUND
  Umbilical cord blood contains relatively abundant primitive CD34(+) hematopoietic progenitor cells which can differentiate into T lymphocytes ex vivo
  
  
  METHODS
  In this study, thymic stromal cells (TSCs) were isolated from aborted fetuses and a monolayer culture system was established. Highly-purified CD34(+) cells from umbilical cord blood were cultured on the TSCs after limiting-dilution. The cells were then harvested and evaluated for CD4, CD8, and CD3 expression at different time points. CD4(+)CD8(-)CD3(-) lymphoid progenitor cells that could differentiate into mature T lymphocytes were observed after 15 days when a cocktail of cytokines, including Flt-3 ligand, stem cell factor, interleukin (IL)-12, and IL-2, was added.
  
  
  RESULTS
  These results thus show that CD4(+)CD8(-)CD3(-) cells can be derived from CD34(+) cells in vitro when cultured on TSCs.
  
  
  CONCLUSIONS
  We showed that CD4(+)CD8(-)CD3(-) cells can be derived from highly purified CD34(+) cells on TSCs during T-cell lymphopoiesis in vitro.
authors.affiliation: Hematopoietic Stem Cell Transplant Center, Bei Tai Ping Lu Hospital, Bei Jing 100039, PRChina. jinjiangang75@163.com
authors.forename: Jian Gang
authors.initials: JG
authors.lastname: Jin
authors.forename: Bao Jun
authors.initials: BJ
authors.lastname: Bai
authors.forename: Zhi Juan
authors.initials: ZJ
authors.lastname: Yao
authors.forename: Ren Na
authors.initials: RN
authors.lastname: Wu
authors.forename: Kai
authors.initials: K
authors.lastname: Feng
authors.forename: Jiang Wei
authors.initials: JW
authors.lastname: Hu
authors.forename: Liang Ding
authors.initials: LD
authors.lastname: Hu
authors.forename: Min
authors.initials: M
authors.lastname: Jiang
authors.forename: Lianming
authors.initials: L
authors.lastname: Liao
authors.forename: Hu
authors.initials: H
authors.lastname: Chen
mesh_terms: D018952:Antigens, CD34 / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D015704:CD4 Antigens / Q000276:immunology; D016827:CD8 Antigens / Q000276:immunology; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology*; D006412:Hematopoietic Stem Cells / Q000276:immunology*; D006801:Humans; D018664:Interleukin-12 / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D038041:Lymphopoiesis / Q000276:immunology*; D008565:Membrane Proteins / Q000378:metabolism; D019089:Stem Cell Factor / Q000378:metabolism; D017154:Stromal Cells / Q000502:physiology; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology
chemical_list: D018952:Antigens, CD34; D017252:CD3 Complex; D015704:CD4 Antigens; D016827:CD8 Antigens; D007376:Interleukin-2; D008565:Membrane Proteins; D019089:Stem Cell Factor; C084881:flt3 ligand protein; D018664:Interleukin-12