A bioassay for serum interferon based on induction of 2'5'-oligoadenylate synthetase activity.
We have developed a bioassay for interferons (IFN) based on measuring the amounts of 2',5' oligoadenylate synthetase (2-5AS) induced in cells of the THP-1 monocyte line in response to IFN. The assay can be completed in 20 h, gives reproducible results, and is at least 50 times more sensitive to IFN-alpha than conventional cytopathic effect inhibition antiviral assays. It is, respectively, less and much less sensitive to IFN-beta and IFN-gamma. The presence of preexisting 2-5AS activity in a sample does not influence the results. We have used this assay to measure very low levels (0.1-0.5 IU/ml) of endogenously formed IFN-alpha in serum samples from patients with various diseases and also to measure the residual small amounts of IFN-alpha still present in the serum as late as 48 h after an i.m. injection of 3 million IU, which is appreciably later than in previous methods. Thus, our highly sensitive assay offers considerable advantages, not least in relation to the clinical use of IFN.
Uno
K
K
Louis Pasteur Center for Medical Research, Kyoto, Japan. lpasteur@mbox.kyoto-inet.or.jp
Sato
T
T
Takada
Y
Y
Fujioka
K
K
Suginoshita
Y
Y
Kakimi
K
K
Moriyasu
F
F
Kishida
T
T
D015088:2',5'-Oligoadenylate Synthetase / Q000378:metabolism*; D001681:Biological Assay; D002460:Cell Line; D016207:Cytokines / Q000494:pharmacology; D004790:Enzyme Induction; D006801:Humans; D007369:Interferon Inducers / Q000494:pharmacology; D016898:Interferon-alpha / Q000097:blood; D007371:Interferon-gamma / Q000097:blood; D007372:Interferons / Q000097:blood*; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism*; D012680:Sensitivity and Specificity; D014777:Virus Diseases / Q000097:blood
D016207:Cytokines; D007369:Interferon Inducers; D016898:Interferon-alpha; D007371:Interferon-gamma; D007372:Interferons; D015088:2',5'-Oligoadenylate Synthetase