title: In vitro self-renewal division of hematopoietic stem cells.
abstract: Little is known about how hematopoietic stem cells (HSCs) self-renew. We studied the regeneration of HSCs in culture. Effects of various cytokines on cell division of CD34(-/low) c-Kit(+)Sca-1(+) lineage marker-negative (CD34(-)KSL) bone marrow cells of the mouse were first evaluated in serum-free single cell culture. We then performed a competitive repopulation assay on divided cells to ask if such cell division involved self-renewal of HSCs. In the presence of stem cell factor (SCF), thrombopoietin (TPO) induced a first cell division of CD34(-)KSL cells more efficiently than did interleukin (IL)-3 or IL-6. Multilineage repopulating cells were detected in a significant proportion of cells derived from single cells in culture with TPO and SCF, although this culture condition led to a substantial decrease in HSC number. These regenerated repopulating cells could be further transplanted into secondary recipients. When paired daughter cells were separately studied, one of a pair gave rise to repopulating cells with self-renewal potential, suggesting asymmetric self-renewal division. This study provides evidence that one HSC regenerates at least one HSC in culture.
authors.affiliation: Department of Immunology, Institute of Basic Medical Sciences, University of Tsukuba and Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tsukuba 305-8575, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Ema
authors.forename: H
authors.initials: H
authors.lastname: Takano
authors.forename: K
authors.initials: K
authors.lastname: Sudo
authors.forename: H
authors.initials: H
authors.lastname: Nakauchi
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D001772:Blood Cell Count; D016026:Bone Marrow Transplantation; D002455:Cell Division / Q000187:drug effects; D019070:Cell Lineage / Q000187:drug effects; D002478:Cells, Cultured; D002999:Clone Cells / Q000166:cytology / Q000187:drug effects / Q000637:transplantation; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000187:drug effects; D007378:Interleukins / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D019089:Stem Cell Factor / Q000494:pharmacology; D013926:Thrombopoietin / Q000494:pharmacology
chemical_list: D018952:Antigens, CD34; D015415:Biomarkers; D007378:Interleukins; D019089:Stem Cell Factor; D013926:Thrombopoietin