Innate Immune Response to Viral Infections at the Maternal-Fetal Interface in Human Pregnancy

Area of Science:

• Reproductive immunology
• Maternal-fetal medicine
• Pathogen-host interactions

Background:

• The placenta is crucial for fetal development and acts as a barrier against pathogens.
• Specialized immune cells, decidual Natural Killer (dNK) cells and macrophages (dMφ), are abundant in early pregnancy decidua.
• These cells, along with fetal cells, are vital for placental development and preventing vertical pathogen transmission.

Purpose of the Study:

• To review how TORCH and emerging viruses access the placenta.
• To discuss the impact of maternal immune cell activation on placental health and pregnancy outcomes.

Main Methods:

• Literature review of placental immunology and infectious diseases.
• Analysis of pathogen entry mechanisms into the placental environment.
• Examination of intrauterine environment changes due to maternal immune responses.

Main Results:

• Certain pathogens, including TORCH viruses (Toxoplasma, Rubella, Cytomegalovirus, Herpes simplex virus) and emerging viruses (Hepatitis E, Zika, SARS-CoV2), can penetrate the placental barrier.
• Maternal immune cell activation alters the intrauterine environment.
• These alterations contribute to placental diseases and adverse pregnancy outcomes.

Conclusions:

• The placental barrier is vulnerable to specific maternal infections.
• Maternal immune responses can inadvertently harm placental function and fetal development.
• Understanding these interactions is critical for managing pregnancy complications caused by infections.