Serum inhibition of proliferation of serum-free mouse embryo cells.
Serum-free mouse embryo (SFME) cells, derived in medium supplemented with insulin, transferrin, high density lipoprotein, epidermal growth factor, and fibronectin, do not undergo crisis, maintain a predominantly diploid karyotype with no detectable chromosomal abnormalities for well over 100 population doublings in vitro, and are growth inhibited by concentrations of serum that are growth-stimulatory for most cell lines in culture. Serum inhibition of SFME cell proliferation was reversible and was not prevented by addition of the supplements of the serum-free medium, even when added repeatedly during the culture period. The serum effect on SFME cell proliferation could be detected after incubation in serum-containing medium for as little as 8 h. SFME cells in serum-containing medium were arrested in the G1 phase of the cell cycle with a greatly reduced rate of incorporation of precursors into DNA and thymidine kinase activity, while a reduction in rate of incorporation of amino acids into protein was not observed. SFME cultures maintained for extended periods in serum-containing medium underwent a crisis-like period followed by the appearance of variant cells capable of growing in serum-supplemented medium. These cells exhibited abnormal karyotype and were resistant to several inhibitors of proliferation active on the parent SFME cell type.
Rawson
C
C
Department of Biochemistry and Biophysics, Oregon State University, Corvallis 97331-6503.
Loo
D
D
Helmrich
A
A
Ernst
T
T
Natsuno
T
T
Merrill
G
G
Barnes
D
D
D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D002455:Cell Division / Q000187:drug effects*; D002478:Cells, Cultured / Q000187:drug effects*; D003470:Culture Media / Q000494:pharmacology*; D004622:Embryo, Mammalian / Q000166:cytology; D016193:G1 Phase; D014644:Genetic Variation; D006131:Growth Inhibitors / Q000097:blood*; D006854:Hydrocortisone / Q000494:pharmacology; D007371:Interferon-gamma / Q000494:pharmacology; D007621:Karyotyping; D051379:Mice; D008807:Mice, Inbred BALB C; D013936:Thymidine / Q000378:metabolism; D013937:Thymidine Kinase / Q000502:physiology; D014284:Triiodothyronine / Q000494:pharmacology
D000596:Amino Acids; D003470:Culture Media; D006131:Growth Inhibitors; D014284:Triiodothyronine; D007371:Interferon-gamma; D013937:Thymidine Kinase; D013936:Thymidine; D006854:Hydrocortisone