title: The lamina propria of adult human oral mucosa harbors a novel stem cell population.
abstract: The highly regenerative capacity of the human adult oral mucosa suggests the existence of a robust stem cell (SC) population in its lamina propria (OMLP). The purpose of this study was to characterize the availability, growth, immunophenotype, and potency of this presumable SC population. Cells positive for the embryonic stem cell transcription factors Oct4 and Sox2 and for p75 formed distinct cord-like structure in the OMLP. Regardless of donor age, trillions of cells, termed human oral mucosa stem cells (hOMSC), 95% of which express mesenchymal stromal cell markers, were simply, and reproducibly produced from a biopsy of 3-4 x 2 x 1 mm(3). A total of 40-60% of these cells was positive for Oct4, Sox2, and Nanog and 60-80% expressed constitutively neural and neural crest SC markers. hOMSC differentiated in culture into mesodermal (osteoblastic, chondroblastic, and adipocytic), definitive endoderm and ectodermal (neuronal) lineages. Unexpectedly, hOMSC treated with dexamethasone formed tumors consisting of two germ layer-derived tissues when transplanted in severe combined immune deficiency mice. The tumors consisted of tissues produced by neural crest cells during embryogenesis-cartilage, bone, fat, striated muscle, and neural tissue. These results show that the adult OMLP harbors a primitive SC population with a distinct primitive neural-crest like phenotype and identifies the in vivo localization of putative ancestors for this population. This is the first report on ectodermal- and mesodermal-derived mixed tumors formation by a SC population derived from a nonmalignant somatic adult human tissue.
authors.affiliation: Department of Oral Biology, School of Dental Medicine Faculty of Medicine, Tel Aviv University, Tel Aviv, Sheba Medical Center, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Keren
authors.initials: K
authors.lastname: Marynka-Kalmani
authors.forename: Sandra
authors.initials: S
authors.lastname: Treves
authors.forename: Miri
authors.initials: M
authors.lastname: Yafee
authors.forename: Heled
authors.initials: H
authors.lastname: Rachima
authors.forename: Yossi
authors.initials: Y
authors.lastname: Gafni
authors.forename: Malkiel A
authors.initials: MA
authors.lastname: Cohen
authors.forename: Sandu
authors.initials: S
authors.lastname: Pitaru
mesh_terms: D000328:Adult; D053687:Adult Stem Cells / Q000145:classification / Q000166:cytology* / Q000378:metabolism; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology; D019070:Cell Lineage / Q000502:physiology; D002471:Cell Transformation, Neoplastic / Q000378:metabolism; D002478:Cells, Cultured; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000145:classification / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D016513:Mice, SCID; D008875:Middle Aged; D009061:Mouth Mucosa / Q000166:cytology* / Q000502:physiology; D009092:Mucous Membrane / Q000166:cytology / Q000502:physiology; D055815:Young Adult
chemical_list: D015415:Biomarkers