title: Establishment of a specific radioimmunoassay for bovine interferon tau.
abstract: A radioimmunoassay (RIA) was developed for quantification of bovine interferon (bIFN) tau, conceptus secretory protein, which allows for the maintenance of the corpus luteum during early pregnancy. A cDNA coding bIFN tau was derived from cultured trophoblast cells (TBs). Recombinant (r) bIFN tau was produced in a baculovirus expression system with two different viruses. The RIA was a double-antibody competitive binding assay that used anti-bIFN tau antiserum (raised in rabbits) as the primary antibody, a radioiodinated derivative of bIFNtau as the radioactive tracer, and goat anti-rabbit IgG as the secondary antibody. The antibody did not cross-react with rbIFN alpha, recombinant human IFN beta or recombinant ovine IFN tau. The correct recovery of amounts of rbIFN tau indicated good accuracy. Serially concentrated TB conditioned media, paralleled the standard curve for bIFN tau. The intra-assay and inter-assay coefficients of variation at bIFN tau levels of 7.8 and 15.6 ng/mL were 7.1 and 8.1%, and 11.0 and 8.5%, respectively. bIFN tau was directly detected in uterine flushings obtained from cows at Day 16 of pregnancy. In summary, this assay was suitable for the measurement of bIFN tau.
authors.affiliation: Department of Animal Breeding and Reproduction, National Institute of Livestock and Grassland Science, Ibaraki 305-0901, Japan. orca@affrc.go.jp
authors.forename: Hitomi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Masashi
authors.initials: M
authors.lastname: Takahashi
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Nagaya
authors.forename: Makoto
authors.initials: M
authors.lastname: Hirako
authors.forename: Ken
authors.initials: K
authors.lastname: Sawai
authors.forename: Akira
authors.initials: A
authors.lastname: Minamihashi
authors.forename: Shigeki
authors.initials: S
authors.lastname: Inumaru
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Yokomizo
authors.forename: Masaya
authors.initials: M
authors.lastname: Geshi
authors.forename: Akira
authors.initials: A
authors.lastname: Okano
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Okuda
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D001667:Binding, Competitive; D001826:Body Fluids / Q000737:chemistry; D002417:Cattle; D002478:Cells, Cultured; D005260:Female; D005865:Gestational Age; D006801:Humans; D007106:Immune Sera / Q000096:biosynthesis; D007370:Interferon Type I / Q000032:analysis* / Q000096:biosynthesis; D007457:Iodine Radioisotopes; D007553:Isotope Labeling; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000032:analysis* / Q000096:biosynthesis; D011817:Rabbits; D011863:Radioimmunoassay / Q000379:methods*; D011994:Recombinant Proteins / Q000096:biosynthesis; D012680:Sensitivity and Specificity; D012756:Sheep; D014327:Trophoblasts / Q000737:chemistry; D014599:Uterus / Q000378:metabolism
chemical_list: D007106:Immune Sera; D007370:Interferon Type I; D007457:Iodine Radioisotopes; D011257:Pregnancy Proteins; D011994:Recombinant Proteins; C020947:interferon tau