Toward refinement of the colony-forming unit-granulocyte/macrophage clonogenic assay: Inclusion of a metabolic system

This work represents a first attempt to refine the colony-forming unit-granulocyte/macrophage (CFU-GM) clonogenic assay by incorporating liver microsomes and co-factors as a metabolic system into the in vitro test system in response to an ECVAM recommendation [Gribaldo, L., Bueren, J., Deldar, A., Hokland, P., Meredith, C., Moneta, D., Mossesso, P., Parchment, R., Parent-Massin, D., Pessina, A., San Roman, J., Schoeters, G., 1996. The use of in vitro systems for evaluating haematotoxicity. ECVAM Workshop Report 14. ATLA 24, 211–231]. From the comparison of results obtained with the CFU-GM clonogenic assay currently used and with the new experimental protocol, different toxicity on granulocyte/macrophage precursors was demonstrated, when drugs with a known metabolism in vivo were tested.