A New Feeder-Free Technique to Expand Human Embryonic Stem Cells and Induced Pluripotent Stem Cells

The optimal maintenance of human embryonic stem cells (hESC) in vitro is generally observed in the presence of a feeder-layer of mouse embryonic fibroblasts in a serum-containing medium. Various approaches are now available to remove the feeder requirement. Today, the best feeder-free system for the maintenance of hESC and induced pluripotent stem (iPS) cells is based on a serum-replacement medium on a matrice of Matrigel. Some reports have also shown feederfree maintenance of hESC in the presence of laminin, fibronectin, vitronectin or collagen IV. However these combinations are expensive. Here we describe an alternative to the current feeder-free short-term amplification of hESC and iPS cells using culture grade plastic dishes pre-coated with 10-20% fetal calf serum. hESC retain expression of various stem cell markers and also retain the ability to differentiate in vitro. Similar results were observed with human iPS cells. This feeder-free culture system is reliable, convenient and allows for the rapid amplification of hESC and iPS cells to numbers suitable for many cell biology techniques.