title: Non-specific and specific effects of a granulocytic bio-inhibitor on different haematopoietic cell populations.
abstract: The effect of a leucocyte conditioned medium derivative on the 5-125iodo-2'-deoxyuridine (125I-UdR) uptake by 6 haematopoietic cell populations with a simple in vitro assay system was tested. The low doses of the test substance--a putative granulocytic chalone--inhibited significantly the uptake of 125I-UdR only in predominantly granulocytic cell cultures. This inhibition was achieved using micrograms/ml concentrations, which have previously been shown to be inhibitory to normal and malignant granulocytic cells in vivo. The test preparations inhibited the uptake of 125I-UdR in all cell populations (nongranulocytic included) when doses exceeding 10 micrograms/ml were used. The prerequisite for an adequate demonstration of the specificity of a bio-inhibitor is discussed.
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells; D002460:Cell Line; D002478:Cells, Cultured; D003470:Culture Media; D004900:Erythroblasts / Q000187:drug effects; D005260:Female; D006098:Granulocytes / Q000187:drug effects; D006131:Growth Inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D006410:Hematopoiesis / Q000187:drug effects*; D006801:Humans; D007065:Idoxuridine / Q000378:metabolism; D007942:Leukemia, Experimental / Q000097:blood; D007962:Leukocytes / Q000032:analysis; D008214:Lymphocytes / Q000187:drug effects; D051379:Mice; D051381:Rats; D013950:Thymus Gland / Q000166:cytology
chemical_list: D003470:Culture Media; D006131:Growth Inhibitors; D007065:Idoxuridine