International Journal of Cell Cloning, Vol 2, 200-215, Copyright © 1984 by AlphaMed Press
Comparison of the biological activity of two sources of colony- stimulating factor (CSF)
M Bessho
Two possible standard sources of colony-stimulating factor (CSF) have been
available commercially; one is GCT-conditioned medium (GCT-CM) and the
other is T3M-5A-CSF. To clarify their biological activity and determine
whether they can provide a stimulus identical with leukocyte feeders, the
number and the morphology of colonies stimulated by them were compared. A
dose-response study and a mixing experiment between them suggested the
presence of inhibitor(s) in GCT-CM but not in T3M-5A- CSF. Both types of
CSF stimulated mainly granulocytic colonies at day 7. T3M-5A-CSF caused a
dose-dependent increase in macrophagic colonies at day 14. The number of
colonies stimulated by GCT-CM and T3M-5A-CSF did not differ from that of
leukocyte feeders, but the morphology of colonies differed significantly.
These results indicate that there is a qualitative difference in the effect
of GCT-CM and T3M-5A-CSF on human bone marrow cells, and that they do not
supply a stimulus identical with leukocyte feeders. Though GCT-CM and
T3M-5A-CSF are expected to serve as useful tools in the standard CFU-C
assay, we should observe their characteristics and accumulate more
information about their behavior on normal as well as on patient bone
marrow cells.
