Induced Pluripotent Stem Cells (iPSCs) have the potential to be differentiated into any cell type and play an important role in regenerative medicine and cell therapy. The objective of this study includes the integration-free genetic reprogramming of human umbilical vein endothelial cells (HUVEC) from the cord towards iPSCs followed by molecular characterization of the obtained iPSCs for pluripotency markers. HUVEC were cultured and characterized by flow cytometry using the cell surface markers CD105 and CD45. HUVEC were subjected to integration-free cellular reprogramming with episomal plasmids carrying OCT-4, SOX-2, KLF-4, L-MYC, and LIN-28, using the Neon Transfection System for electroporation. Molecular characterization of iPSCs was done by immunofluorescence staining for the nuclear marker OCT-4 and the cell-surface marker TRA-1-81. The HUVEC-derived iPSC colonies started appearing after one week and exhibited a flat appearance with well-defined, rounded edges and tightly packed cells in the center. The iPSCs showed immunofluorescence for the positive pluripotency markers OCT-4 and TRA-1-81. Episomal non-viral-based integration-free and transgene-free cellular reprogramming is a suitable and efficient method for reprogramming cord-derived HUVEC towards iPSCs. These iPSCs can potentially be used for investigating molecular mechanisms in in vitro disease modeling, drug testing, and drug discovery, in addition to their use in Regenerative Medicine and cell therapy.

Keywords: Cellular reprogramming, episomal plasmids, human umbilical vein endothelial cells, induced pluripotent stem cells.