Chemotherapy of malignant diseases is often associated with hematoxicity, well known as doses-limiting toxicity of cytotoxic drugs. It is, therefore, of great clinical interest to investigate newly developed compounds for their ability to suppress hematopoietic cell growth.

For the most part, we have established the Colony Formation Unit (CFU) assay assay for screening purposes of agents with assumably hematotoxic activity. The functions of hematopoietic stem cells to form colonies in-vitro will be determined by Colony Formation Units as hallmark of viable cells. In particular, after incubation of the desired test substance at different concentrations for 8 to 14 days, we analyse the percentage of the formed colonies of different hematopoietic cell types. On the basis of these findings we hypothesize the degree of hematotoxic activity of a specific compound on these subpopulations.