The effects of Flk-2/flt3 ligand as compared with c-kit ligand on short-term and long-term proliferation of CD34+ hematopoietic progenitors elicited from human fetal liver, umbilical cord blood, bone marrow, and mobilized peripheral blood.
The Flk-2/flt3 ligand (FL) was evaluated and compared with c-kit ligand (KL) for its in vitro proliferative effects on CD34+ cells from human fetal liver, umbilical cord blood, bone marrow, and mobilized peripheral blood. Using a 7-day liquid culture system, FL in combination with interleukin-3 (IL-3), interleukin-6 (IL-6), and granulocyte colony-stimulating factor (G-CSF) was comparable with KL in combination with IL-3, IL-6, and G-CSF for the expansion of hematopoietic progenitors. When FL-containing cultures were assayed after 21 or 28 days, a greater number of progenitors were generated as compared with KL-containing cultures. Using bone marrow microvascular endothelial cells as support stroma, cultures supplemented with FL generated a greater number of progenitors in both the nonadherent and adherent layers at day 35. These data suggest that FL ligand, in combination with other cytokines, can be used for short-term ex vivo expansion of hematopoietic progenitors and facilitates the preservation and possible expansion of primitive cells capable of long-term generation of progenitors.
Shapiro
F
F
Department of Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
Pytowski
B
B
Rafii
S
S
Witte
L
L
Hicklin
D J
DJ
Yao
T J
TJ
Moore
M A
MA
D018952:Antigens, CD34; D001773:Blood Cells / Q000166:cytology*; D001854:Bone Marrow Cells; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D005260:Female; D005312:Fetal Blood / Q000166:cytology*; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D008099:Liver / Q000166:cytology* / Q000196:embryology; D008565:Membrane Proteins / Q000494:pharmacology*; D009928:Organ Specificity; D011247:Pregnancy; D019089:Stem Cell Factor / Q000494:pharmacology*
D018952:Antigens, CD34; D008565:Membrane Proteins; D019089:Stem Cell Factor; C084881:flt3 ligand protein