Expression of leukemia inhibitory factor and its receptor is not altered in the decidua and chorionic villi of human anembryonic pregnancy.

BACKGROUND

Uterine expression of leukemia inhibitory factor (LIF) is absolutely essential for mouse, and critical for human, embryo implantation. However LIF is not required for post-implantation development of mouse embryo. The objective of this study was to examine the role of LIF system in post-implantation stage of human pregnancy.

METHODS

Tissues from 25 patients with anembryonic pregnancy (AP; blighted ovum) and 25 matched patients with normal pregnancy (NP) were collected. LIF and its receptor beta (LIF-Rbeta) expression in the decidua and chorionic villi were analyzed by semi-quantitative reverse transcription and polymerase chain reaction (RT-PCR), real-time quantitative PCR and immunohistochemical study.

RESULTS

LIF mRNA levels were not different either between different tissues (decidua vs chorionic villi) or between different patients (NP vs AP). LIF-Rbeta mRNA levels were significantly higher in chorionic villi than in decidua but were not different between NP and AP. Immunohistochemical staining supported these findings and showed a predominate expression of LIF-Rbeta in the trophoblast cells.

CONCLUSIONS

This study concluded that at early human post-implantation stage, LIF is produced from both decidua and chorionic villi and may exert its major action on trophoblasts. A baseline expression of LIF and LIF-Rbeta is probably needed for early pregnancy, but AP cannot be accounted for by the defective expression of either LIF or LIF-Rbeta in most circumstances.