title: Radioimmunoassay of tumor necrosis factor in serum.
abstract: We present a double-antibody radioimmunoassay for determination of the concentration of tumor necrosis factor (TNF) in serum. TNF in serum competes with a fixed amount of 125I-labeled TNF for the binding sites of specific rabbit antibodies. The bound TNF is precipitated with Sepharose-bound anti-rabbit IgG, then centrifuged, and the radioactivity of the pellets is counted. The detection limit of the assay is 7 ng/L (B0-3 SD). Bound radioactivity in the range of 10% to 90% of the B0 counts corresponds to TNF concentrations of 26 to 10,000 ng/L. Of 40 sera from healthy subjects, 21 (53%) contained TNF concentrations greater than 7 ng/L (range 8-40 ng/L). Some patients with parasitic or neoplastic disease and patients with septic shock had highly increased TNF values. Three of the 14 sera (21%) from patients with rheumatoid arthritis had TNF concentrations greater than 40 ng/L.
authors: IV Department of Medicine, University Central Hospital, Helsinki, Finland.
authors: A M
authors: AM
authors: Teppo
authors: C P
authors: CP
authors: Maury
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000097:blood; D001424:Bacterial Infections / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000097:blood; D010272:Parasitic Diseases / Q000097:blood; D011786:Quality Control; D011863:Radioimmunoassay; D011994:Recombinant Proteins; D012016:Reference Values; D014409:Tumor Necrosis Factor-alpha / Q000097:blood*
chemical_list: D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha