International Journal of Cell Cloning, Vol 4, 103-114, Copyright © 1986 by AlphaMed Press
Serum-free culture of primitive murine hemopoietic colony-forming cells
P Baines, F Cormier, N Lucien and GA Boffa
We report the effect of four sources of hemopoietic growth factors, alone
or in combination, on colony growth in serum-free cultures of bone marrow
from normal mice or marrow from mice pre-treated with 5- fluorouracil
(5-FU-bm). The four supplements were: mouse spleen conditioned medium (SCM,
a source of multi-lineage colony-stimulating activity, multi-CSA), human
placental conditioned medium (HPCM, a source of synergistic activity),
pregnant mouse uterus extract (PMUE, a source of M-CSA) and erythropoietin
(Epo). First, in cultures of normal marrow, only PMUE and SCM induced
significant colony growth when added alone. The majority of those colonies
contained granulocytes and macrophages (myeloid colonies). In
Epo-supplemented cultures, only SCM supported the growth of erythroid
bursts and mixed erythroid-myeloid colonies. HPCM thus appears to be a poor
source of multi-CSA. Second, in cultures of 5-FU-bm, few colonies developed
if any of the above supplements were added alone. Only SCM + Epo together
stimulated the formation of a low number of very large, mixed
erythroid/myeloid/megakaryocyte colonies. HPCM, but not SCM, synergized
with PMUE to augment myeloid colony numbers. Hence, SCM appears to be a
poor source of synergistic activity (SA). In cultures of 5-FU-bm already
supplemented with HPCM + PMUE, the addition of Epo did not change total
colony numbers but did induce erythroid differentiation in one third of the
colonies present. These data suggest that multi-CSA and SA may be expressed
by different factors and that 5-FU pre-treated marrow contains: a
population of primitive multipotential progenitors which form large, mixed
colonies in the presence of SCM + Epo, and a larger Epo-sensitive
population which also requires HPCM + PMUE to form mixed colonies.
