title: Enhanced proliferation and differentiation of Oct4- and Sox2-overexpressing human adipose tissue mesenchymal stem cells.
abstract: Mesenchymal stem cells (MSCs) are attractive candidates for clinical repair or regeneration of damaged tissues. Oct4 and Sox2, which are essential transcription factors for pluripotency and self-renewal, are naturally expressed in MSCs at low levels in early passages, and their levels gradually decrease as the passage number increases. Therefore, to improve MSC proliferation and stemness, we introduced human Oct4 and Sox2 for conferring higher expansion and differentiation capabilities. The Oct4-IRES-Sox2 vector was transfected into human adipose tissue MSCs (ATMSCs) by liposomal transfection and used directly. Oct4 and Sox2 were successfully transfected into ATMSCs, and we confirmed maintenance of MSC surface markers without alterations in both red fluorescent protein (RFP) (control) and Oct4/Sox2-ATMSCs. Enhanced proliferative activity of Oct4/Sox2-ATMSCs was shown by WST-1 assay, and this result was further confirmed by cell counting using trypan blue exclusion for a long period. In addition, FACs cell cycle analysis showed that there was a reduction in the fraction of Oct4/Sox2-ATMSCs in G1 with a concomitant increase in the fraction of cells in S, compared with RFP-ATMSCs. Increased levels of cyclin D1 were also seen in Oct4/Sox2-ATMSCs, indicating acceleration in the transition of cells from G1 to S phase. Furthermore, Oct4/Sox2-overexpressing ATMSCs showed higher differentiation abilities for adipocytes or osteoblasts than controls. The markers of adipogenic or osteogenic differentiation were also upregulated by Oct4/Sox2 overexpression. The improvement in cell proliferation and differentiation using Oct4/Sox2 expression in ATMSCs may be a useful method for expanding the population and increasing the stemness of ATMSCs.
authors.affiliation: Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.
authors.forename: Sei-Myoung
authors.initials: SM
authors.lastname: Han
authors.affiliation: Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.
authors.forename: Sang-Hun
authors.initials: SH
authors.lastname: Han
authors.affiliation: Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.
authors.forename: Ye-Rin
authors.initials: YR
authors.lastname: Coh
authors.affiliation: Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.
authors.forename: Goo
authors.initials: G
authors.lastname: Jang
authors.affiliation: Stem Cell Research Center, K-STEMCELL Co. Ltd., Seoul, Republic of Korea.
authors.forename: Jeong
authors.initials: J
authors.lastname: Chan Ra
authors.affiliation: Stem Cell Research Center, K-STEMCELL Co. Ltd., Seoul, Republic of Korea.
authors.forename: Sung-Keun
authors.initials: SK
authors.lastname: Kang
authors.affiliation: Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.
authors.forename: Hee-Woo
authors.initials: HW
authors.lastname: Lee
authors.affiliation: 1] Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea [2] Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.
authors.forename: Hwa-Young
authors.initials: HY
authors.lastname: Youn
mesh_terms: D000273:Adipose Tissue / Q000166:cytology; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000378:metabolism*; D055748:SOXB1 Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D050814:Octamer Transcription Factor-3; C494173:POU5F1 protein, human; C527782:SOX2 protein, human; D055748:SOXB1 Transcription Factors