title: The molecular nature of very small embryonic-like stem cells in adult tissues.
abstract: Pluripotent stem cells (PSCs) have been considered as the most important cells in regenerative medicine as they are able to differentiate into all types of cells in the human body. PSCs have been established from several sources of embryo tissue or by reprogramming of terminally differentiated adult tissue by transduction of so-called Yamanaka factors (Oct4, Sox2, Klf4, and cMyc). Interestingly, accumulating evidence has demonstrated the residence of PSCs in adult tissue and with the ability to differentiate into multiple types of tissue-committed stem cells (TCSCs). We also recently demonstrated that a population of pluripotent Oct4(+) SSEA-1(+)Sca-1(+)Lin(-)CD45(-) very small embryonic-like stem cells (VSELs) resides in the adult murine bone marrow (BM) and in other murine tissue. These very small (∼3-6 μm) cells express pluripotent markers such as Oct4, Nanog, and SSEA-1. VSELs could be specified into several tissue-residing TCSCs in response to tissue/organ injury, and thus suggesting that these cells have a physiological role in the rejuvenation of a pool of TCSCs under steady-state conditions. In this review article, we discuss the molecular nature of the rare population of VSELs which have a crucial role in regulating the pluripotency, proliferation, differentiation, and aging of these cells.
authors.affiliation: Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Korea ; Department of Physiology, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: YongHwan
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Korea ; Department of Physiology, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jaeho
authors.initials: J
authors.lastname: Jeong
authors.affiliation: Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Korea ; Department of Physiology, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Hyunsook
authors.initials: H
authors.lastname: Kang
authors.affiliation: Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Korea ; Department of Physiology, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jisun
authors.initials: J
authors.lastname: Lim
authors.affiliation: Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Korea ; Department of Physiology, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jinbeom
authors.initials: J
authors.lastname: Heo
authors.affiliation: Stem Cell Institute at the James Graham Brown Cancer Center, University of Louisville, KY, USA.
authors.forename: Janina
authors.initials: J
authors.lastname: Ratajczak
authors.affiliation: Stem Cell Institute at the James Graham Brown Cancer Center, University of Louisville, KY, USA.
authors.forename: Mariusz Z
authors.initials: MZ
authors.lastname: Ratajczak
authors.affiliation: Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Korea ; Department of Physiology, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Dong-Myung
authors.initials: DM
authors.lastname: Shin
keywords: DNA Methylation; Genomic Imprinting; PGC; Pluripotency; VSEL