title: Treatment of human embryos with the TGFβ inhibitor SB431542 increases epiblast proliferation and permits successful human embryonic stem cell derivation.
abstract: OBJECTIVE
  Is there an effect of the TGFβ inhibitor SB431542 (SB) on the epiblast compartment of human blastocysts, and does it affect subsequent human embryonic stem cell (hESC) derivation?
  
  
  CONCLUSIONS
  SB increases the mean number of NANOG-positive cells in the inner cell mass (ICM), and allows for subsequent hESC derivation.
  
  
  BACKGROUND
  It is known that inhibition of TGFβ by SB has a positive effect on mouse ESC self-renewal, while active TGFβ signalling is needed for self-renewal of primed ESC.
  
  
  METHODS
  From December 2011 until March 2012, 263 donated spare embryos were used from patients who had undergone IVF/ICSI in our centre.
  
  
  METHODS
  Donated human embryos were cultured in the presence of SB or Activin A, and immunocytochemistry was performed on Day 6 blastocysts for NANOG and GATA6. Moreover, blastocysts were used for the derivation of hESC, with or without exposure to SB.
  
  
  RESULTS
  Immunocytochemistry revealed a significantly higher number of NANOG-positive ICM cells in the SB group compared with the control (12.0 ± 5.9 versus 6.1 ± 4.7), while no difference was observed in the Activin A group compared with other groups (6.7 ± 3.7). The number of GATA6-positive ICM cells did not differ between the SB, Activin A and control group (8.8 ± 4.3, 8.0 ± 4.6 and 7.2 ± 4.0, respectively). Blocking TGFβ signalling did not prevent subsequent hESC line derivation.
  
  
  CONCLUSIONS
  The number of human blastocysts available for this study was too low to reveal if the observed increase in NANOG-positive epiblast cells after exposure to SB affected the efficiency of hESC derivation (12.5% compared with 16.7%).
  
  
  CONCLUSIONS
  This work can contribute to the derivation of naive hESC lines in the future.
  
  
  BACKGROUND
  M.V.d.J. is holder of a Ph.D. grant of the Agency for Innovation by Science and Technology (IWT, grant number SB093128), Belgium. G.D. and this research are supported by the Research Foundation Flanders (FWO), grant number FWO-3G062910) and a Concerted Research Actions funding from BOF (Bijzonder Onderzoeksfonds University Ghent, grant number BOF GOA 01G01112). S.M.C.d. S.L. is supported by the Netherlands Organization of Scientific Research (NWO) (ASPASIA 015.007.037) and the Interuniversity Attraction Poles (PAI) (no. P7/07). P.D.S. is holder of a fundamental clinical research mandate by the FWO. We would like to thank Ferring Company (Aalst, Belgium) for financial support of this study. The authors do not have any competing interests to declare.
  
  
  BACKGROUND
  Not applicable.
authors.affiliation: Department for Reproductive Medicine, Ghent University Hospital, De Pintelaan 185, Ghent 9000, Belgium.
authors.forename: Margot
authors.initials: M
authors.lastname: Van der Jeught
authors.forename: Björn
authors.initials: B
authors.lastname: Heindryckx
authors.forename: Thomas
authors.initials: T
authors.lastname: O'Leary
authors.forename: Galbha
authors.initials: G
authors.lastname: Duggal
authors.forename: Sabitri
authors.initials: S
authors.lastname: Ghimire
authors.forename: Sylvie
authors.initials: S
authors.lastname: Lierman
authors.forename: Nadine
authors.initials: N
authors.lastname: Van Roy
authors.forename: Susana M
authors.initials: SM
authors.lastname: Chuva de Sousa Lopes
authors.forename: Tom
authors.initials: T
authors.lastname: Deroo
authors.forename: Dieter
authors.initials: D
authors.lastname: Deforce
authors.forename: Petra
authors.initials: P
authors.lastname: De Sutter
mesh_terms: D028341:Activins / Q000494:pharmacology; D001549:Benzamides / Q000494:pharmacology*; D002460:Cell Line; D049109:Cell Proliferation; D004149:Dioxoles / Q000494:pharmacology*; D046149:Embryo Culture Techniques / Q000379:methods; D004622:Embryo, Mammalian / Q000187:drug effects*; D053595:Embryonic Stem Cells / Q000166:cytology*; D005855:Germ Layers / Q000166:cytology* / Q000187:drug effects; D018398:Homeodomain Proteins / Q000096:biosynthesis; D006801:Humans; D000071317:Nanog Homeobox Protein; D016212:Transforming Growth Factor beta / Q000037:antagonists & inhibitors* / Q000502:physiology
chemical_list: C459179:4-(5-benzo(1,3)dioxol-5-yl-4-pyridin-2-yl-1H-imidazol-2-yl)benzamide; D001549:Benzamides; D004149:Dioxoles; D018398:Homeodomain Proteins; C486780:NANOG protein, human; D000071317:Nanog Homeobox Protein; D016212:Transforming Growth Factor beta; C422405:activin A; D028341:Activins
keywords: TGFβ inhibition; epiblast; human embryo development; human embryonic stem cell (hESC) derivation; naive hESC