title: Expression pattern of the CCAAT/enhancer-binding proteins C/EBP-alpha, C/EBP-beta and C/EBP-delta in the human placenta.
abstract: The human trophoblast has the capacity to invade maternal tissue in a controlled fashion and to produce a wide range of hormones. The transcription factors belonging to the CCAAT/enhancer-binding protein (C/EBP) family are regulators of intracellular processes and mediators of hormone action. C/EBP binding sites have been described in the promoters of several placenta-expressed target genes. In the present study, we used immunohistochemistry and Western-blot analysis to investigate the expression pattern of the three most important members of this family, C/EBP-alpha, -beta, and -delta, in the normal human placenta as well as in isolated trophoblast cell populations. We found C/EBP-alpha and C/EBP-beta expression in the villous syncytiotrophophoblast (ST) and the extravillous (intermediate) trophoblast (EVT), but it was absent from the villous cytotrophoblast (CT). Interestingly, expression of C/EBP-beta continued to be very strong up to the third trimester of pregnancy, especially in the ST. C/EBP-delta showed overall lower expression levels, stronger only in the EVT, while CT/ST showed very low/negative expression. These data show for the first time the expression pattern and tissue localization of C/EBP factors in the human placenta, indicating that these factors (especially C/EBP-beta) may play important roles in the regulation of placenta-specific genes and processes.
authors.affiliation: Department of Gynecopathology, Institute of Pathology, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany. abamberger@uke.uni-hamburg.de
authors.forename: Ana-Maria
authors.initials: AM
authors.lastname: Bamberger
authors.forename: Antonis
authors.initials: A
authors.lastname: Makrigiannakis
authors.forename: Martina
authors.initials: M
authors.lastname: Schröder
authors.forename: Christoph M
authors.initials: CM
authors.lastname: Bamberger
authors.forename: Constantine
authors.initials: C
authors.lastname: Relakis
authors.forename: Birgit
authors.initials: B
authors.lastname: Gellersen
authors.forename: Karin
authors.initials: K
authors.lastname: Milde-Langosch
authors.forename: Thomas
authors.initials: T
authors.lastname: Löning
mesh_terms: D015153:Blotting, Western; D022762:CCAAT-Enhancer-Binding Proteins / Q000096:biosynthesis*; D002478:Cells, Cultured; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011264:Pregnancy Trimesters; D014327:Trophoblasts / Q000378:metabolism
chemical_list: D022762:CCAAT-Enhancer-Binding Proteins