title: The new stem cell biology.
abstract: Recent studies have indicated that bone marrow stem cells are capable of generating muscle, cardiac, hepatic, renal, and bone cells. Purified hematopoietic stem cells have generated cardiac and hepatic cells and reversed disease manifestations in these tissues. Hematopoietic stem cells also alter phenotype with cell cycle transit or circadian phase. During a cytokine stimulated cell cycle transit, reversible alterations of differentiation and engraftment occur. Primitive hematopoietic stem cells express a wide variety of adhesion and cytokine receptors and respond quickly with migration and podia extensions on exposure to cytokines. These data suggest an "Open Chromatin" model of stem cell regulation in which there is a fluctuating continuum in the stem cell/progenitor cell compartments, rather than a hierarchical relationship. These observations, along with progress in using low dose treatments and tolerization approaches, suggest many new therapeutic strategies involving stem cells and the creation of a new medical specialty; stemology.
authors.affiliation: Department of Research, Roger Williams Medical Center, 825 Chalkstone Avenue, Providence, RI 02908, USA. pquesenberry@rwmc.org
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Quesenberry
authors.forename: Gerald A
authors.initials: GA
authors.lastname: Colvin
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Lambert
authors.forename: Angela E
authors.initials: AE
authors.lastname: Frimberger
authors.forename: Mark S
authors.initials: MS
authors.lastname: Dooner
authors.forename: Christina I
authors.initials: CI
authors.lastname: Mcauliffe
authors.forename: Caroline
authors.initials: C
authors.lastname: Miller
authors.forename: Pamela
authors.initials: P
authors.lastname: Becker
authors.forename: Evangelis
authors.initials: E
authors.lastname: Badiavas
authors.forename: Vincent J
authors.initials: VJ
authors.lastname: Falanga
authors.forename: Gerald
authors.initials: G
authors.lastname: Elfenbein
authors.forename: Lawrence G
authors.initials: LG
authors.lastname: Lum
mesh_terms: D000818:Animals; D002469:Cell Separation; D002678:Chimera; D002843:Chromatin / Q000235:genetics; D005260:Female; D015870:Gene Expression; D006410:Hematopoiesis; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000502:physiology; D006801:Humans; D008297:Male; D051379:Mice; D020297:Mice, Congenic; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008954:Models, Biological; D009369:Neoplasms / Q000628:therapy; D014184:Transplantation, Homologous; D014185:Transplantation, Isogeneic
chemical_list: D002843:Chromatin