Serum-free culture of enriched murine haemopoietic stem cells. I: Effect of haemopoietic growth factors on proliferation.

AbstractUsing a population of cells highly enriched for multipotential day 12 spleen colony forming cells (CFU-S) (termed the FACS-BM population), and a serum-free culture system, the requirements for development of multipotential cell have been investigated and compared to previous results using serum containing cultures. In both serum-free and serum supplemented cultures interleukin-3 (IL-3) was a potent colony stimulating factor, although it was more effective in serum free conditions. However, colony stimulation by granulocyte-macrophage colony stimulating factor (GM-CSF) and macrophage-colony stimulating factor (M-CSF) was markedly reduced in the absence of serum. Significantly, the ability of inter-leukin-1 (IL-1) and granulocyte-colony stimulating factor (G-CSF) to synergise with these two growth factors was retained in serum-free conditions, indicating that these growth factors act directly on the FACS-BM without serum co-factors. Furthermore synergistic interactions between IL-3 plus IL-1, and IL...