title: Very small embryonic-like stem cells: characterization, developmental origin, and biological significance.
abstract: Bone marrow (BM) was, for many years, primarily envisioned as the "home organ" of hematopoietic stem cells (HSC). Augmenting evidence demonstrates, however, that BM, in addition to HSC, also contains a heterogeneous population of non-HSC. Recently, our group identified in BM and other adult tissues a population of very small embryonic-like stem cells (VSELs), which express several markers characteristic for pluripotent stem cells that are characteristic for epiblast/germ line-derived stem cells. Thus, we hypothesize that VSELs are a population of epiblast-derived cells that are deposited during early gastrulation in developing tissues/organs and play an important role in turnover of tissue-specific/committed stem cells. In this context, VSELs deposited in BM can give rise to long-term repopulating HSC. VSELs could be also mobilized into peripheral blood (PB), and the number of these cells circulating in PB increases during stress and tissue/organ injuries. Finally, we envision that in pathological situations VSELs are involved in development of some malignancies (e.g., teratomas, germinal tumors).
authors.affiliation: Stem Cell Institute at James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA. mzrata01@louisville.edu
authors.forename: Mariusz Z
authors.initials: MZ
authors.lastname: Ratajczak
authors.forename: Ewa K
authors.initials: EK
authors.lastname: Zuba-Surma
authors.forename: Marcin
authors.initials: M
authors.lastname: Wysoczynski
authors.forename: Janina
authors.initials: J
authors.lastname: Ratajczak
authors.forename: Magda
authors.initials: M
authors.lastname: Kucia
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology* / Q000502:physiology; D002454:Cell Differentiation; D048429:Cell Size; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000502:physiology; D006801:Humans; D051379:Mice; D023421:Models, Animal; D008954:Models, Biological; D039904:Pluripotent Stem Cells / Q000166:cytology / Q000502:physiology; D033581:Stem Cell Transplantation