title: CD29 of human umbilical cord mesenchymal stem cells is required for expansion of CD34(+) cells.
abstract: OBJECTIVE
  Human umbilical cord mesenchymal stem cells (hUCMSCs) play a critical role in expanding haematopoietic stem cells (HSCs) by providing the essential microenvironment for haematopoiesis. In this study, we sought to investigate whether CD29 of hUCMSCs would play a key role in the ability of hUCMSCs to help expand HSCs in vivo and in vitro.
  
  
  METHODS
  To investigate whether CD29 of hUCMSCs would play a key role for the ability of hUCMSCs to expand HSCs, soluble anti-CD29 antibody was added to co-cultures of hUCMSCs and cord blood (CB) CD34(+) cells. It significantly blocked expansion of CB CD34(+) cells induced by hUCMSCs. Using CD29-deficient hUCMSCs models, long-term culture-initiating cell and non-obese diabetic/severe combined immunodeficient disease mouse repopulating cell assay, revealed that CB CD34(+) cells co-cultured with CD29-deficient hUCMSCs only retained the capacity of multipotent differentiation for 5 weeks at the most.
  
  
  RESULTS
  Soluble anti-CD29 antibody significantly blocked expansion of CB CD34(+) cells induced by hUCMSCs. CB CD34(+) cells co-cultured with CD29-deficient hUCMSCs only retained the capacity of multipotent differentiation for 5 weeks at the most.
  
  
  CONCLUSIONS
  CB CD34(+) cells co-cultured with CD29-deficient hUCMSCs gave rise to all major haematopoietic lineages, but failed to engraft long term.
authors.affiliation: Department of Medical Genetics, School of Basic Medical Sciences, Peking University, Beijing, 100191, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Yang
authors.forename: M
authors.initials: M
authors.lastname: Hu
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Li
authors.forename: Z
authors.initials: Z
authors.lastname: Miao
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000378:metabolism*; D002478:Cells, Cultured; D018920:Coculture Techniques; D005312:Fetal Blood / Q000166:cytology*; D006410:Hematopoiesis; D006801:Humans; D019012:Integrin beta1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D014183:Transplantation, Heterologous
chemical_list: D018952:Antigens, CD34; D019012:Integrin beta1; D034741:RNA, Small Interfering