title: Thyroxine binding by hepatitis B surface antigen.
abstract: Thyroxine and triiodothyronine binding sites are present on the 20-nm spherical particles associated with hepatitis B surface antigen (HBsAg). Thyroxine-treated HBsAg has a buoyant density of 1.26 g/cm-3 in CsCl and appears under the electron microscope as a hexagonal particle with a center-to-vertex distance of 10 nm. These results provoke questions concerning the origin of thyroid hormone binding sites on HBsAg and a possible relationship between thyroid status and HBsAg antigenemia in humans.
mesh_terms: D001666:Binding Sites, Antibody; D002462:Cell Membrane / Q000276:immunology*; D002500:Centrifugation, Isopycnic; D002501:Centrifugation, Zonal; D004586:Electrophoresis; D006511:Hepatitis B Antigens; D006801:Humans; D008854:Microscopy, Electron; D013974:Thyroxine / Q000378:metabolism*; D013975:Thyroxine-Binding Proteins; D014284:Triiodothyronine / Q000378:metabolism
chemical_list: D006511:Hepatitis B Antigens; D013975:Thyroxine-Binding Proteins; D014284:Triiodothyronine; D013974:Thyroxine