title: High-affinity receptors for human interferon in bovine lung and human placenta.
abstract: Membrane fractions were prepared from fresh frozen bovine lung tissue and human placenta and used for receptor binding studies with recombinant DNA produced human-alpha-interferon (IFN-alpha). A single class of high-affinity binding sites was determined for bovine lung (Ka = 1.5 X 10(10) M) and human placenta (Ka = 3.7 X 10(9) M) membranes, respectively. These values for the affinity of IFN binding are comparable within the range of observed error to that observed for the binding of human IFN-alpha 2 to cultured Daudi cells (Ka = 2.5 X 10(10) M). The type I IFN receptor content of bovine lung and human placenta membranes was 1.3 and 2.5 fmoles/mg wet weight, respectively. In addition, alterations in specific and nonspecific binding were observed with the bovine lung membrane incubations in the presence of calcium. Increases in specific binding of three- to fourfold were observed in the presence of 1 mM calcium chloride.
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D002417:Cattle; D005260:Female; D006801:Humans; D007370:Interferon Type I / Q000378:metabolism*; D007700:Kinetics; D008168:Lung / Q000276:immunology / Q000378:metabolism*; D008566:Membranes / Q000378:metabolism; D010920:Placenta / Q000276:immunology / Q000378:metabolism*; D011247:Pregnancy; D011971:Receptors, Immunologic / Q000378:metabolism*; D017471:Receptors, Interferon
chemical_list: D007370:Interferon Type I; D011971:Receptors, Immunologic; D017471:Receptors, Interferon