title: Stem cells and the endocrine pancreas.
abstract: BACKGROUND
  Diabetes can be treated by β-cell replacement therapy but the supply of graft material from human donors is too limited to make a significant clinical impact. Substitute β-cells generated from stem cell populations offer a potential source for the large numbers of cells required.
  
  
  METHODS
  Primary peer-reviewed reports of experimental studies.
  
  
  RESULTS
  Embryonic stem cells and/or induced pluripotent stem (iPS) cells are currently the most promising starting populations from which to generate large numbers of β-cells. Differentiation protocols that recapitulate in vivo development generate insulin-expressing cells in vitro.
  
  
  RESULTS
  Differentiation outcomes may depend on the source of the initial pluripotent cells. The insulin-expressing cells are not fully functional. In vivo maturation is inconsistent and not well understood.
  
  
  CONCLUSIONS
  Improvement of current protocols for complete in vitro differentiation to a functional β-cell phenotype. Systematic analysis to identify the most appropriate starting material. Improved purification methods to ensure safety of material for clinical transplantation.
authors.affiliation: Diabetes Research Group, King's College London, London, UK.
authors.forename: Yue
authors.initials: Y
authors.lastname: Wu
authors.forename: Shanta J
authors.initials: SJ
authors.lastname: Persaud
authors.forename: Peter M
authors.initials: PM
authors.lastname: Jones
mesh_terms: D003922:Diabetes Mellitus, Type 1 / Q000628:therapy*; D053595:Embryonic Stem Cells / Q000637:transplantation; D006801:Humans; D050417:Insulin-Secreting Cells / Q000637:transplantation*; D007515:Islets of Langerhans / Q000166:cytology; D039904:Pluripotent Stem Cells / Q000637:transplantation; D033581:Stem Cell Transplantation / Q000379:methods*