title: Lanthanide ion enhancement of interferon binding to cells.
abstract: Pretreatment of purified [125I]-labeled human and mouse beta interferons (IFN) with lanthanum chloride (LaCl3) enhanced 20-30 fold the binding of the [125I]-IFNs to human A549 and mouse L cells at 0 degree C and also enhanced antiviral activity in homologous cells. Although lanthanides enhanced cross-species binding of both human and mouse [125I]-IFNs, there was no increase in cross-species antiviral activity. Unlabeled IFN not treated with LaCl3 did not compete with [125I]-IFN treated with LaCl3 for cellular receptors. However, unlabeled IFN treated with LaCl3 did compete with LaCl3-treated [125I]-IFN. These results suggest that lanthanide treated IFNs do not bind to the same receptors as native IFNs.
mesh_terms: D000818:Animals; D002460:Cell Line; D006801:Humans; D007370:Interferon Type I / Q000378:metabolism*; D007811:Lanthanum / Q000494:pharmacology*; D051379:Mice; D011485:Protein Binding / Q000187:drug effects; D011971:Receptors, Immunologic / Q000378:metabolism*; D017471:Receptors, Interferon; D013045:Species Specificity; D015018:Ytterbium / Q000494:pharmacology*
chemical_list: D007370:Interferon Type I; D011971:Receptors, Immunologic; D017471:Receptors, Interferon; D007811:Lanthanum; D015018:Ytterbium