Sustained embryoid body formation and culture in a non-laborious three dimensional culture system for human embryonic stem cells.

Pluripotent human embryonic stem cell (hESC) lines are a promising model system in developmental and tissue regeneration research. Differentiation of hESCs towards the three germ layers and finally tissue specific cell types is often performed through the formation of embryoid bodies (EBs) in suspension or hanging droplet culture systems. However, these systems are inefficient regarding embryoid body (EB) formation, structural support to the EB and long term differentiation capacity. The present study investigates if agarose, as a semi solid matrix, can facilitate EB formation and support differentiation of hESC lines. The results showed that agarose culture is able to enhance EB formation efficiency with 10% and increase EB growth by 300%. The agarose culture system was able to maintain expression of the three germ layers over 8 weeks of culture. All of the four hESC lines tested developed EBs in the agarose system although with a histological heterogeneity between cell lines as well as within cell lines. In conclusion, a 3-D agarose culture of spherical hESC colonies improves EB formation and growth in a cost effective, stable and non-laborious technique.