Soluble tumor necrosis factor receptors (TNFR) and interleukin-6 receptor (IL-6R) in human pregnancy

Abstract

SOLUBLE TUMOR NECROSIS FACTOR RECEPTORS (TNFR) AND INTERLEUKIN-6 RECEPTOR (IL-6R) IN HLrM_AN PREGNANCY SL Opsjen a, D Novick b, NC Wathen '~ and D Aderka b (~University Hospital of Trondheim, Norway, *~eizmann Institute of Science, Rehovot, Israel and St. Bartholomew's Hospital, London, UK) The TNFRs p55 and p75 and IL-6R were examined in extraembryonic coelomic (eec) fluid, amniotic fluid, maternal and cord serum. Samples were retrieved from 137 women and analysed by ELISA. In first trimester all receptors were present in high concentrations in eec fluid and low in the corresponding amniotic fluid. In second trimester they increased, but while TNFRs decreased at term, IL-6R was unchanged. No receptors were changed by onset of spontanous labor. In maternal serum no difference in TNFRs were seen between nonpregnant and first trimester pregnancy. They increased at term, with a further increment with onset of labor. TNFRs in cord sera were not affected by labor. IL-6R was detected in maternal and cord sera but was not affected by gestational age or onset of labor. In amniotic fluid variation of TNF and IL-6 may be reflected in change of their receptors during pregnancy, but not with onset of labor. The variation in TNFRs in maternal serum throughout pregnancy and labor corresponds with serum levels of IL-6. A.57 ANALYSIS OF THE TRANSCRIPTIONAL ELEMENTS INVOLVED IN THE PLACENTA-SPECIFIC EXPRESSION OF THE HUMAN PLACENTAL LACTOGEN GENES. C~cile Oury, Patrick Jaquemin, Alexandra Belayew and J.A. Martial. Laboratoire de Biologie Mol(~culaire et de G~nie G6n~tique, Universit(~ de Liege, Sart Tilman, Belgium. Human placental lactogen (hCS) and human growth hormone (hGH) genes are clustered on chromosome 17 in the following order : 5' hGH-N/hCS-L/hGH-V/hCS-A/ hCS-B 3'. Despite their similarity, these genes are expressed at different levels and in t w o separate tissues. HGH is secreted by somatotrophs of the anterior pituitary whereas hCS is produced by syncytiotrophoblasts in the placenta. So far, a single placenta-specific enhancer has been found, 2 kilobases downstream from the hCS-B gene, at the 3' and of the cluster. Protection against DNase I digestion in this region reveals four binding sites for nuclear proteins from either placental or HeLa cells ( DF-1, DF-2, DF-3 and DF-4). In transient expression experiments where the regulatory elements have been linked to a TKCAT reporter gene and introduced in JEG-3 cells, the placenta-specific enhancer activity is mediated by a aynergy between the DF-3 and DF-4 sites ( covering a 126 base pairs fragment). Morever, gel retardation assays indicate that a same protein or set of proteins, different in HeLa and placental cell nuclei, interact with sites DF-2, DF-3 and DF-4. Analysis of the sequences of these three sites indicate an homology between a part of them and TEF-1 binding sites. We also studied the regions of the hCS-L and hCS-A genes which are highly similar to the hCS-B enhancer. Although each present the four protein-binding sites ( except for the 5' part of the hCS-A DF-2 site), they exhibit only minor enhancer activity. In fact, we provide evidence that the hCS-A DF-2 site, if placed before the 126 bp hCS-B enhancer, can reduce the later activity in JEG-3 cells.