title: Identification of human leukemic glucocorticoid receptors using affinity labeling and anti-human glucocorticoid receptor antibodies.
abstract: Antisera raised against human lymphoid glucocorticoid receptors were used in combination with the glucocorticoid receptor affinity label [3H]dexamethasone 21-mesylate [( 3H]DM) to identify the glucocorticoid receptors of the human B-lymphoblastoid cell line IM-9 and the human T-cell leukemic cell line CEM-C7. Antisera were obtained following immunization of New Zealand White rabbits with [3H]triamcinolone acetonide [( 3H]TA)-glucocorticoid receptor complexes partially purified by two-stage DNA-cellulose chromatography. The presence of anti-human glucocorticoid receptor antibodies was verified by: (a) adsorption of [3H]TA-receptor-antibody complexes to Protein A; (b) a shift to higher apparent molecular weight in the elution position from Sephacryl S300 of [3H]TA-receptor complexes incubated with immune serum; and (c) the ability of immune serum to displace [3H]TA-receptor complexes on sucrose gradients. These antibodies also recognized rat liver and murine S49 cell glucocorticoid receptors. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of [3H]DM-labeled IM-9 cytosol identified a major competable band with a molecular weight of approximately 90,000, three minor competable components with molecular weights of approximately 78,000, approximately 51,000, and approximately 38,500, and at least 21 other noncompetable components. Following immunoprecipitation of [3H]DM-labeled cytosol with immune serum, only the Mr 90,000 and 78,000 components were seen. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of [3H]DM-labeled CEM-C7 cytosol revealed a larger number of [3H]DM-labeled components. However, after immunoprecipitation of [3H]DM-labeled CEM-C7 cytosol, a predominant competable component with a molecular weight of 90,000 was easily identified. This component was markedly diminished when cytosols from the glucocorticoid receptor-deficient cell line ICR-27 were used. Thus, the combination of affinity labeling and anti-human glucocorticoid receptor antibodies is capable of providing direct physical identification of human lymphoid glucocorticoid receptors.
mesh_terms: D000345:Affinity Labels / Q000378:metabolism; D000906:Antibodies; D000936:Antigen-Antibody Complex; D001402:B-Lymphocytes / Q000032:analysis; D002460:Cell Line; D003600:Cytosol / Q000032:analysis; D003907:Dexamethasone / Q000031:analogs & derivatives / Q000378:metabolism; D006801:Humans; D007945:Leukemia, Lymphoid / Q000378:metabolism*; D008970:Molecular Weight; D011965:Receptors, Glucocorticoid / Q000032:analysis*; D011987:Receptors, Steroid / Q000032:analysis*; D014222:Triamcinolone Acetonide / Q000378:metabolism
chemical_list: D000345:Affinity Labels; D000906:Antibodies; D000936:Antigen-Antibody Complex; D011965:Receptors, Glucocorticoid; D011987:Receptors, Steroid; D003907:Dexamethasone; D014222:Triamcinolone Acetonide; C031710:dexamethasone 21-methanesulfonate