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Published on: March 16, 2017
Human chorionic gonadotropin beta-core fragment is present in the human placenta
A Udagawa1, T Okamoto, S Nomura
1Department of Obstetrics and Gynecology, Nagoya University School of Medicine, Japan.
Molecular and Cellular Endocrinology
|August 15, 1998
Summary
The human placenta contains the hCG beta-core fragment (beta-core), confirmed by specific assays. This fragment is secreted by trophoblasts and found in placental tissue, with lower levels in maternal serum.
Area of Science:
- Reproductive Biology
- Endocrinology
- Biochemistry
Background:
- The presence of human chorionic gonadotropin (hCG) beta-core fragment (beta-core) in placental tissue has been a subject of debate.
- Understanding hCG beta-core's role is crucial for reproductive health research.
Purpose of the Study:
- To definitively establish the presence and localization of beta-core in the human placenta.
- To investigate the secretion and levels of beta-core in placental cultures and maternal circulation.
Main Methods:
- Development of a highly specific enzyme immunoassay for beta-core.
- Analysis of placental extracts, organ culture supernatants, and primary trophoblast cultures.
- Immunohistochemistry and Western blot analysis of placental tissue and biological fluids.
Main Results:
- Beta-core immunoreactivity was detected in all placental samples, constituting at least 5% of intact hCG immunoreactivity.
- Immunohistochemistry localized beta-core to the syncytiotrophoblast.
- Western blot revealed two major bands (~15 kDa) in placental culture supernatants and urine; serum levels were significantly lower (0.1-0.19% of intact hCG).
Conclusions:
- The human placenta actively produces and potentially secretes the beta-core fragment.
- Reduced beta-core levels in maternal serum may be attributed to its short half-life in blood.
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