Characterization of PBMC-originated, iPSC-derived CECs following cryopreservation. (a) qRT-PCR analysis of CE-associated markers: AQP1, ATP1A1, ATP1A3, COL4A1, COL4A3, COL8A1, COL8A2, FOXC1, and SLC16A3 on day 20 (D20). (b–d) Immunostaining for zona occludens-1 (ZO-1; a tight-junction protein) exhibiting typical hexagonal/polygonal morphology of CECs. The images are 60× magnification, and the scale bar represents 10 μm.