Stimulation of hCG protein and mRNA in first trimester villous cytotrophoblast cells in vitro by glycodelin A

Aim: Human chorionic gonadotropin (hCG) is produced by fetal
trophoblast cells and secreted into maternal circulation mainly in
the first trimester of pregnancy. Another glycoprotein, glycodelin
A, is one of the main products of the maternal decidua during this
period. The purpose of this study was to investigate the effect of
glycodelin A on hCG release by isolated cytotrophoblast cells in
vitro. Methods: Cytotrophoblast cells were prepared from human
first trimester placenta and incubated with varying concentrations
of glycodelin A. Supernatants were assayed for hCG protein
concentrations, and quantification of beta hCG mRNA was carried out
by RT-PCR. Expression of hCG was analysed in stimulated trophoblast
cells and in unstimulated controls by immunocytochemistry. Results:
Glycodelin A induces a dose-dependent increase of hCG production.
An increase of hCG expression was measured at 100 and 200 mu g/mL
glycodelin-A treatment in trophoblast cell culture by TaqMan assay
on mRNA level. We found a moderate staining of hCG in control
trophoblast cells, whereas a strong hCG staining was seen in
glycodelin A-treated trophoblast cells. Conclusions: HCG is a
marker for the differentiation process of trophoblast cells. Our
results suggest that glycodelin A secreted by the decidualized
endometrium is involved in the regulation of hormones produced by
the trophoblast.