Further studies on the mechanism of CFU-S determination--I. Pluripoietin(s) responsible for CFU-S determination toward granulopoiesis after fractionated doses of Ara-C.
Fractionated doses of Ara-C orient CFU-S differentiation towards granulopoiesis and megakaryocytopoiesis in vivo in contrast to the preferential channelling towards erythropoiesis after a similar dose of Ara-C given as a single injection. In this paper, we show that pluripoietin found in the serum of mice treated with fractionated doses of Ara-C is responsible for the choice of CFU-S differentiation towards granulopoiesis. Therefore, we confirm our previous results involving single doses of Ara-C, that humoral factors can commit CFU-S preferentially towards one of the cell lineages. It is not as yet known whether there is a specific pluripoietin for each cell lineage or whether the same pluripoietin has a different effect according to its concentration in the organism. The difference in response of CFU-S commitment to single and fractionated doses of Ara-C is not due to the difference in the kinetic status of CFU-S:CFU-S are cycling after both treatments.
D000818:Animals; D003561:Cytarabine / Q000494:pharmacology*; D004920:Erythropoiesis; D005260:Female; D006098:Granulocytes; D006410:Hematopoiesis / Q000187:drug effects*; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000187:drug effects; D008094:Lithium / Q000494:pharmacology; D008222:Lymphokines / Q000097:blood*; D008297:Male; D008533:Megakaryocytes; D051379:Mice; D008808:Mice, Inbred CBA
D008222:Lymphokines; D003561:Cytarabine; D008094:Lithium