[Inhibitors of bone marrow stem cells proliferation. Possible applications during chemotherapy (author's transl)]

An inhibitor of bone marrow stem cell (CFU-S) proliferation, prepared from fetal calf marrow, was administered to mice during sequential treatments with Cytosine Arabinoside. Results show that the percentage of CFU-S survival is significantly increased when the inhibitor is given simultaneously with the drug. A purified fraction of the inhibitor obtained by chromatography permitted survival of mice receiving lethal doses of Cytosine Arabinoside. The inhibit seems to be specific for CFU-S and has no effect on EMT6 tumor cells in vitro. Since it is not specific for the animal species, its clinical use could be envisaged to protect bone marrow during chemotherapy.