The primary cultured ESCs we used were confirmed immunocytochemically to be positive for vimentin, a marker for stromal cells, and negative for cytokeratin, a marker for epithelial cells (please see above figure). ESCs at early passages (between 2 and 6 passages) were used for the experiment. In this study, the passaged cells were used without freezing. However, we have confirmed that primary ESCs can be cryopreserved in CELLBANKER, and retain characteristics such as responsiveness to decidual stimuli. These descriptions have been added to the revised manuscript (page 3, lines 96-99).
The result must be shown for at least each ESC cell culture (each culture or patient named separately) obtained from each patient to demonstrate that the described results are representative of multiple patients, and not potentially atypical results from an atypical patient.