Presence of oestrogen receptors in human blood mononuclear cells and thymocytes
Weusten, J.J.; Blankenstein, M.A.; Gmelig-Meyling, F.H.; Schuurman, H.J.; Kater, L.; Thijssen, J.H.
Acta Endocrinologica 112(3): 409-414
1986
ISSN/ISBN: 0001-5598 PMID: 3489342 Document Number: 280577
We studied oestrogen binding sites in blood mononuclear cells from healthy blood donors, patients with leukaemia or systemic lupus erythematosus, and in thymocytes, using the dextran-coated charcoal assay and Scatchard analysis of binding data. Using 3H-labelled oestradiol as ligand, inaccurate results were obtained which could be related to the low amounts of binding sites. Using 125I-labelled ligand, saturable oestradiol binding sites could be demonstrated in low amount (mean value 2.1 fmol/mg of cytosolic protein) and high affinity (mean Kd value 0.26 nM; mean Ka value 3.85 .times. 109 M-1). The binding could be inhibited by unlabelled oestradiol but not with oestrone, dihydrotestosterone, cortisol and the progestin-receptor ligand Org 2058. We conclude that blood mononuclear cells and thymocytes contain true oestrogen receptors. This conclusion supports current hypotheses on the involvement of such receptors in oestrogen-mediated modulation of the immune system.