In vitro myelopoiesis stimulated by rapid medium exchange and
supplementation with hematopoietic growth factors
RM Schwartz, SG Emerson, MF Clarke and BO Palsson
Department of Chemical Engineering, University of Michigan, Ann Arbor.
We studied the effect of the combination of rapid culture medium exchange
with the addition of the human hematopoietic growth factors interleukin-3
(IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), and
erythropoietin (Epo) on the proliferation and differentiation of human
long-term bone marrow cultures (LTBMCs). Individually and in combinations,
IL-3, GM-CSF, and Epo were added to the culture medium of LTBMCs that were
maintained with 50% medium volume exchange per day. The combination of IL-3
+ GM-CSF + Epo generated the most prolific cultures with an order of
magnitude increase in nonadherent cell production from weeks 2 through 8 in
culture as compared with unsupplemented controls. Under these conditions,
the cultures produced as many cells as were inoculated every 2 weeks and
led to a greater than 2.5-fold expansion in terms of the number of
nonadherent cells produced over a 6- to 8-week period. Furthermore, the
LTBMCs produced nonadherent colony-forming unit-GM (CFU-GM) for more than
20 weeks. The rapid medium exchange combined with the addition of human
hematopoietic CSFs significantly enhances the proliferation and
differentiation of LTBMCs. These results indicate that addition of
combinations of hematopoietic CSFs, together with a rapid medium exchange
rate, can provide culture conditions that are suitable for the expansion of
the progenitor cell pool and perhaps for the increased survival of
hematopoietic stem cells in culture. Although these culture conditions
still fall short of full reconstitution of functional human bone marrow,
they provide an improved approach to hematopoietic cell culture that may
permit the expansion and manipulation of progenitor cells in vitro.
Volume 78,
Issue 12,
pp. 3155-3161,
12/15/1991
Copyright © 1991 by The American Society of Hematology
