title: Tumor necrosis factor receptors in HeLa cells and their regulation by interferon-gamma.
abstract: Incubation of HeLa cell cultures with human interferon-gamma (IFN-gamma) increased the binding of radioiodinated human tumor necrosis factor (TNF) to specific cell surface receptors (TNF-R). IFN-gamma also produced a proportionate increase in receptor-mediated endocytosis of TNF. TNF-R expression was significantly increased after 6 h of exposure to IFN-gamma (100 units/ml), and it remained elevated in the continuous presence of IFN-gamma for at least 20 h. Incubation of cells with IFN-gamma in the presence of cycloheximide, followed by treatment with actinomycin D and reversal of the inhibition of protein synthesis, also resulted in increased TNF-R expression as compared to cultures subjected to the same treatments in the absence of IFN-gamma. These results suggest that IFN-gamma can directly stimulate accumulation of the mRNA for TNF-R and that TNF-R is among the cellular proteins whose synthesis is increased by IFN-gamma.
mesh_terms: D003513:Cycloheximide / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells / Q000032:analysis*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis; D011956:Receptors, Cell Surface / Q000032:analysis* / Q000378:metabolism; D018124:Receptors, Tumor Necrosis Factor; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha
chemical_list: D006023:Glycoproteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D003609:Dactinomycin; D007371:Interferon-gamma; D003513:Cycloheximide