Granulocyte colony-stimulating factor mobilizes primitive hematopoietic stem cells in normal individuals.
We studied the hematopoietic activity of peripheral blood stem cells (PBSC) mobilized by recombinant human granulocyte colony-stimulating factor (G-CSF) using semisolid and long-term culture systems (LTC) in 5 normal individuals. Following 2 or 3 daily subcutaneous injections of G-CSF (filgrastim; 1.5 micrograms/kg), not only committed progenitors including CFU-GM, BFU-E, and CFU-Mix, but also long-term culture initiating cells (LTC-IC) were increased in the peripheral blood. When the cells derived from CFU-GM, BFU-E and CFU-Mix colonies were replated for secondary colony formation, a minor fraction of CFU-GM and CFU-Mix colonies formed after 3 days of G-CSF stimulation in vivo could produce secondary colonies. Moreover, the replating capacity of primary colonies from 5-week-old LTC initiated after 3 days of G-CSF stimulation was increased compared to that from 5-week-old LTC initiated in a 'steady-state'. These observations indicate that G-CSF can mobilize very primitive progenitors (LTC-IC) along with committed progenitors into the circulation and suggest that some of these G-CSF-mobilized progenitors may retain self-renewal capacity.
Fujisaki
T
T
First Department of Internal Medicine, Faculty of Medicine, Fukuoka, Japan.
Otsuka
T
T
Harada
M
M
Ohno
Y
Y
Niho
Y
Y
D000328:Adult; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects; D006801:Humans; D007279:Injections, Subcutaneous; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins / Q000008:administration & dosage
D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor