Krt15

Cells were fixed with 4% PFA for 20 minutes and permeabilized with 0.1% Triton X-100 for 10 minutes. Subsequently, the cells were blocked with 5% BSA for 60 minutes and incubated with primary antibodies against PAX6 (Thermo Fisher Scientific), TP63, Ki67 (Boster), KRT19, KRT15, KRT12 or KRT3 (Santa Cruz Biotechnology, Inc.) at instructed dilutions overnight in a cold room. Cells were washed with PBS at least 3 times and 15 minutes each time before incubation with the isotype-matching secondary antibodies (all from Invitrogen). The cell nuclei were counterstained with 4, 6-diamidino-2-phenylindole (DAPI). Bright-field and fluorescent images were captured using the Carl Zeiss Axio Observer. To check the expression of CEC markers on the recellularized DC and in sections of mouse skin tissues as controls, we processed the samples the same way and incubated with antibodies against human PAX6, KRT1, KRT10, KRT12, KRT14, KRT15, and VINCULIN (Abcam, Cambridge, United Kingdom), and mouse MHC Class I (Abcam), followed by secondary antibodies against the isotype of the primary antibodies and counterstaining with DAPI. Bright field and fluorescent images were captured with Carl Zeiss Axio Observer. All primary and secondary antibodies above were used at the dilution of 1:200 and 1:1,000, respectively.