title: C/EBPβ is involved in the amplification of early granulocyte precursors during candidemia-induced "emergency" granulopoiesis.
abstract: Granulopoiesis is tightly regulated to meet host demands during both "steady-state" and "emergency" situations, such as infections. The transcription factor CCAAT/enhancer binding protein β (C/EBPβ) plays critical roles in emergency granulopoiesis, but the precise developmental stages in which C/EBPβ is required are unknown. In this study, a novel flow cytometric method was developed that successfully dissected mouse bone marrow cells undergoing granulopoiesis into five distinct subpopulations (#1-5) according to their levels of c-Kit and Ly-6G expression. After the induction of candidemia, rapid mobilization of mature granulocytes and an increase in early granulocyte precursors accompanied by cell cycle acceleration was followed by a gradual increase in granulocytes originating from the immature populations. Upon infection, C/EBPβ was upregulated at the protein level in all the granulopoietic subpopulations. The rapid increase in immature subpopulations #1 and #2 observed in C/EBPβ knockout mice at 1 d postinfection was attenuated. Candidemia-induced cell cycle acceleration and proliferation of hematopoietic stem/progenitors were also impaired. Taken together, these data suggest that C/EBPβ is involved in the efficient amplification of early granulocyte precursors during candidemia-induced emergency granulopoiesis.
authors.affiliation: Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507, Japan.
authors.forename: Sakiko
authors.initials: S
authors.lastname: Satake
authors.forename: Hideyo
authors.initials: H
authors.lastname: Hirai
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Hayashi
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Shime
authors.forename: Akihiro
authors.initials: A
authors.lastname: Tamura
authors.forename: Hisayuki
authors.initials: H
authors.lastname: Yao
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yoshioka
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Miura
authors.forename: Tohru
authors.initials: T
authors.lastname: Inaba
authors.forename: Naohisa
authors.initials: N
authors.lastname: Fujita
authors.forename: Eishi
authors.initials: E
authors.lastname: Ashihara
authors.forename: Jiro
authors.initials: J
authors.lastname: Imanishi
authors.forename: Teiji
authors.initials: T
authors.lastname: Sawa
authors.forename: Taira
authors.initials: T
authors.lastname: Maekawa
mesh_terms: D000818:Animals; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D058387:Candidemia / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D005434:Flow Cytometry / Q000379:methods; D005784:Gene Amplification / Q000276:immunology*; D006098:Granulocytes / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D023461:Myeloid Progenitor Cells / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D013997:Time Factors
chemical_list: D022782:CCAAT-Enhancer-Binding Protein-beta