International Journal of Cell Cloning, Vol 1, 61-78, Copyright © 1983 by AlphaMed Press
Colony-stimulating activity in murine mixed leukocyte cultures
A Horikoshi, J Rossio and MJ Murphy Jr
Mixed leukocyte cultures (MLC) were prepared utilizing mouse spleen cells
from strains with: (1) major histocompatibility complex (MHC) differences,
(2) many non-MHC gene differences, and (3) only a few non- MHC gene
differences. After 4 days, the conditioned media (CM) of MLC from (1) and
(2) above were found to contain high granulocyte/macrophage
colony-stimulating activity (CSA) when assayed in methylcellulose clonal
cultures. Also the stimulation index (SI) of CSA was elevated on day 4 of
incubation, even though 3H-Thymidine (3HTdR) incorporation and SI as
measured by 3HTdR increased at 4 and 6 days, respectively. However, MLC-CM
from mouse strains with only a few non-MHC gene differences contained low
titers of CSA after 4 days in culture, and this was paralleled by a low SI.
For MLC with MHC differences, and with many non-MHC gene differences, the
response detected by an increase in CSA production appeared more promptly
and was perhaps more sensitive when compared with 3HTdR incorporation in
the mixed leukocyte reaction (MLR). From these results, we conclude that
the presence of CSA in MLC-CM at 4 days of culture represents a good marker
for the degree of MLR, and we postulate that the CSA titer in MLC-CM may be
relevant for the prediction of graft-versus-host reactions (GvHR).
