title: Control of CFUc proliferation by selective endogenous inhibitors.
abstract: The susceptibility of mouse bone marrow colony forming cells (CFUc) to three different types of proliferation inhibitors in capillary semisolid agar gel was studied. GI-3, a target specific peptide containing granulocyte fraction, T4-1, an oligospecific thymic factor of proteid nature, and the alkylating cytostatics dianhydrogalactitol (DAD) inhibit myeloid colony formation as a function of concentration. The respective MED values amount to 8, 10, and 0.002 microgram/ml. When compared with this same parameter 3H-TdR incorporation into DNA of liquid bone marrow cultures showed a single fold charge for the endogenous inhibitors (GI-3, T4-1) for the cytostatic (DAD) a 3 to 4 fold lower difference. It was demonstrated, that in competitive antagonism of GI-3 and colony stimulating factor the inhibitor prevails over CSF.
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D003115:Colony-Stimulating Factors / Q000494:pharmacology; D003961:Dianhydrogalactitol / Q000494:pharmacology; D006412:Hematopoietic Stem Cells; D008297:Male; D051379:Mice; D010455:Peptides / Q000494:pharmacology; D013950:Thymus Gland / Q000032:analysis
chemical_list: D003115:Colony-Stimulating Factors; D010455:Peptides; D003961:Dianhydrogalactitol