title: Immunocytochemical demonstration of erythropoietin in hypoxic human hepatoma cultures.
abstract: The possibility of demonstrating erythropoietin at the light microscopic level was examined in homogenous cultures of the erythropoietin-producing human hepatoma cell lines HepG2 and Hep3B. Immunoperoxidase staining was applied in combination with several mono- and polyclonal antibodies. Sufficiently strong colour responses were obtained with all three polyclonal antibodies and with one of three monoclonal antibodies raised against recombinant human erythropoietin. The staining intensity was increased in hypoxic versus nonhypoxic hepatoma cultures. Intracellular erythropoietin immunoreactivity was confirmed by Western blot analysis of HepG2 extracts. The effect of oxygen supply on erythropoietin gene expression was confirmed by competitive polymerase chain reaction of erythropoietin mRNA and by radioimmunoassay of secreted erythropoietin.
authors.affiliation: Physiologisches Institut I, Rheinische Friedrich-Wilhelms-Universität, Bonn, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Herkens
authors.forename: M
authors.initials: M
authors.lastname: Wolff
authors.forename: J
authors.initials: J
authors.lastname: Fandrey
authors.forename: F
authors.initials: F
authors.lastname: Schuler
authors.forename: W
authors.initials: W
authors.lastname: Jelkmann
mesh_terms: D000818:Animals; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000276:immunology / Q000378:metabolism*; D015687:Cell Hypoxia; D004921:Erythropoietin / Q000276:immunology / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D007381:Intermediate Filament Proteins / Q000276:immunology; D007668:Kidney / Q000166:cytology / Q000378:metabolism; D008113:Liver Neoplasms / Q000276:immunology / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis; D013552:Swine; D014407:Tumor Cells, Cultured
chemical_list: D007381:Intermediate Filament Proteins; D012333:RNA, Messenger; D004921:Erythropoietin