Cell reprogramming and transfection

Episomal vectors (pCXLE-hOCT3/4-shp53-F, pCXLE-hSK, pCXLE-hUL and pCXLE-EGFP) were obtained from Addgene (Cambridge, MA, USA) and introduced into HSC2 cells in various combinations. An expression plasmid mixture containing one or more of these episomal vectors (1 μg of each vector) were electroporated into 6 × 10⁵ HSC2 cells with Neon Transfection System (Thermo Fisher scientific) using a 100 μl kit according to the manufacturer’s instructions (conditions for electroporation: pulse voltage: 1550 or 1650 V, pulse width: 10 ms, pulse number: 3). In the same way, we inserted pCXLE-EGFP only into HSC2 cells to obtain HSC2/EGFP as a control. The list of expression plasmid mixtures used in the experiments and the resultant cells is shown in Table 1.

Summary of plasmid mixtures for electroporation