title: Reproducible, ultra high-throughput formation of multicellular organization from single cell suspension-derived human embryonic stem cell aggregates.
abstract: BACKGROUND
  Human embryonic stem cells (hESC) should enable novel insights into early human development and provide a renewable source of cells for regenerative medicine. However, because the three-dimensional hESC aggregates [embryoid bodies (hEB)] typically employed to reveal hESC developmental potential are heterogeneous and exhibit disorganized differentiation, progress in hESC technology development has been hindered.
  
  
  RESULTS
  Using a centrifugal forced-aggregation strategy in combination with a novel centrifugal-extraction approach as a foundation, we demonstrated that hESC input composition and inductive environment could be manipulated to form large numbers of well-defined aggregates exhibiting multi-lineage differentiation and substantially improved self-organization from single-cell suspensions. These aggregates exhibited coordinated bi-domain structures including contiguous regions of extraembryonic endoderm- and epiblast-like tissue. A silicon wafer-based microfabrication technology was used to generate surfaces that permit the production of hundreds to thousands of hEB per cm(2).
  
  
  CONCLUSIONS
  The mechanisms of early human embryogenesis are poorly understood. We report an ultra high throughput (UHTP) approach for generating spatially and temporally synchronised hEB. Aggregates generated in this manner exhibited aspects of peri-implantation tissue-level morphogenesis. These results should advance fundamental studies into early human developmental processes, enable high-throughput screening strategies to identify conditions that specify hESC-derived cells and tissues, and accelerate the pre-clinical evaluation of hESC-derived cells.
authors.affiliation: Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Ungrin
authors.forename: Chirag
authors.initials: C
authors.lastname: Joshi
authors.forename: Andra
authors.initials: A
authors.lastname: Nica
authors.forename: Céline
authors.initials: C
authors.lastname: Bauwens
authors.forename: Peter W
authors.initials: PW
authors.lastname: Zandstra
mesh_terms: D018929:Cell Culture Techniques; D002469:Cell Separation / Q000379:methods; D053595:Embryonic Stem Cells / Q000166:cytology*; D006801:Humans; D009024:Morphogenesis; D018874:Spheroids, Cellular / Q000166:cytology*; D023822:Tissue Engineering / Q000379:methods*