0000000000634290
AUTHOR
U. Moebius
16α-Iodo-3,17β-estradiol: A stable ligand for estrogen receptor determinations in tissues with high 17β-hydroxysteroid dehydrogenase activity
Recently, the successful synthesis of radioiodinated 16 alpha-iodo-3,17 beta-estradiol-[125I] [125I]E2 was reported [1]. This new ligand has similar binding characteristics to the estrogen receptor (ER) [2-5] as the currently used tritium labeled estradiol [3H]E2. However, it offers several advantageous features: (a) high specific activity (theoretically 2,000 Ci/mmol) [1]; (b) minor problems with radioactive waste due to its short half life and (c) the possibility of simultaneous determination of ER and progesterone receptors (PgR) by double labeling with [125I]E2 and [3H]R5020 [6, 7]. As we are presently trying to determine ER and PgR in human placental cytosols we were interested in the …
Definition of discrete signals involved in human T-cell activation
Abstract Mitogenic activities of monoclonal antibodies directed at denned receptor structures expressed on the surface of mature human T lymphocytes were employed to study, in detail, signals involved in primary T-cell activation. Based on differential requirements for stimulation, two discrete pathways of human T-cell activation can be defined: the antigen-induced mode of activation initiated through the Ti-T3 antigen-receptor complex and an alternative pathway which can be triggered by monoclonal antibodies directed at the T11 glycoprotein. Perhaps more importantly, the approach taken here allows the definition of stable intermediate cellular stages within the activation cascade and, thus…