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Updated: Mar 26, 2026
05:22
Ex vivo Culture of Human Placental Explants for the Study of Viral Transmission Across the Maternal-Fetal Interface
Published on: December 30, 2025
337
Expression and function of endogenous retroviruses in the placenta
1Robert Koch Institute, Berlin, Germany.
Summary
Endogenous retroviruses, known as syncytins, are crucial for placenta development and successful pregnancy by enabling cell fusion. Their immunosuppressive role in preventing embryo rejection is supported by evidence of their presence in maternal tissues.
Area of Science:
- Reproductive Biology
- Virology
- Immunology
Background:
- Endogenous retroviruses (ERVs) have long been observed in placental tissues across species.
- Recent research has elucidated their critical physiological roles during gestation.
Purpose of the Study:
- To investigate the function of retroviral envelope proteins (syncytins) in placental development.
- To explore the potential immunosuppressive role of syncytins in preventing maternal rejection of the semi-allogeneic embryo.
Main Methods:
- Analysis of syncytin expression in placental tissues.
- Observation of syncytin-expressing cells within maternal tissues.
Main Results:
- Syncytin expression facilitates the fusion of trophoblast cells, forming the multinuclear syncytiotrophoblast, essential for placental development.
- The presence of syncytin-expressing placenta cells amidst maternal immune cells suggests a role in immune modulation.
Conclusions:
- Syncytins derived from endogenous retroviruses are vital for placentogenesis and successful pregnancy.
- Endogenous retroviruses have been evolutionarily "enslaved" by different species for placental development, often involving multiple ERVs per species.
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