ESTROGEN-RECEPTORS IN MACROPHAGES

The presence of receptors for oestradiol‐17β and 5α‐dihydrotestosterone(5α‐DHT) in the human monocytic leukaemia cell line JIII and rat peritoneal macrophages was investigated using whole‐cell assays. For both cell types. high‐affinity binding species for oestrogen were detected, whereas no indication of specific binding was observed for 5α‐DHT. Analysis of the data according to Scatchard showed curved lines, indicating the presence of two different oestrogen‐binding species. The dissociation constant (Kd) values for the receptors of the rat peritoneal maorophages were calculated to be 1.4 × 10‐10M and 3.3 × 10‐9M, while for the JIII cells, the Kd values were 8.7 × 10‐11M and 2.5 × 10‐9M. Sucrose‐gradient ultracentrifugation identified one oestrogenbinding species or 7.IS. The receptors had a relatively high affinity for diethylstilboestrol (DES) but did not bind to a monoelonal antibody specific for the classical oestrogen receptor, suggesting that oestrogen receptors in macrophages could be of a different type. Copyright © 1990, Wiley Blackwell. All rights reserved