title: A sensitive biological assay for interferons.
abstract: Several assays are available for interferons that either measure activity (bioassays) or protein mass (ELISAs). Bioassays generally require the use of viruses and some means of determining cell killing. Many investigators lack the expertise to work with potentially harmful viral agents and eschew this approach in favor of an ELISA assay based on a specific antibody or, to obtain the high level of sensitivity usually required, a combination of antibodies. Such immunological assays, while relatively easy, are expensive and detect protein mass which is not a reliable index of biological activity. I describe here a bioassay based on induction of a reporter gene linked to an interferon (IFN)-responsive promoter element. Production of the reporter gene product is dose-dependent in the range of 1 to approximately 100 U/ml of IFN and sensitivity is comparable to standard cytopathic effect assays. The assay can be modified to quantitate or detect other IFNs and could be applied to other cytokines.
authors.affiliation: Department of Anatomy and Cell Biology, SUNY Health Science Center at Brooklyn 11203, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Lewis
mesh_terms: D000818:Animals; D001681:Biological Assay; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D019204:GTP-Binding Proteins / Q000235:genetics; D015870:Gene Expression / Q000187:drug effects; D007371:Interferon-gamma / Q000032:analysis*; D051379:Mice; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics
chemical_list: D012333:RNA, Messenger; D007371:Interferon-gamma; D015500:Chloramphenicol O-Acetyltransferase; D019204:GTP-Binding Proteins