PARTIAL CHARACTERIZATION OF AN IMMORTALIZED HUMAN TROPHOBLAST CELL-LINE, TCL-1, WHICH POSSESSES A CSF-1 AUTOCRINE LOOP

Many previous studies in both mouse and human placenta have implicated a role for colony stimulating factor-1 (CSF-1) in the regulation of p lacental development. In this study we have examined CSF-1 production by an immortalized cell line (TCL-1) derived from the choriodecidua, t ransfected with a retrovirus gene coding for the large-T antigen. TCL- 1 cells were uniformly positive by immunocytochemistry for the composi te sub-units of human chorionic gonadotrophin (hCG) but were negative for markers of other cell types localized at the fetal-maternal interf ace. Gelatinase enzymes were secreted by TCL-1 cells cultured on extra cellular matrix in a manner indicative of extra-villous trophoblast. D ot-blot immunoassays and ELISA indicated that CSF-1 was secreted by TC L-1 cells, at levels comparable to primary trophoblast cells and BeWo choriocarcinoma (trophoblast tumour) cells. reverse transcriptase-poly merase chain reaction analysis confirmed the presence in TCL-1 cells o f CSF-1 receptor mRNA (c-fms gene product), indicating that the compon ents of a potential autocrine loop were present in these cells. Prolif eration of TCL-1 cells was not affected by the addition of exogenous C SF-1 but was elevated in response to treatment with a CSF-1 neutralizi ng antibody. The immortalized cell line, TCL-1, provides a potential m odel in which to investigate regulation of growth and differentiation of trophoblast cells in vitro. (C) 1996 W. B. Saunders Company Ltd