Prenatal Stress, Anxiety and Depression Alter Transcripts, Proteins and Pathways Associated with Immune Responses at the Maternal-fetal Interface†

During pregnancy, the immune system is modified to allow developmental tolerance of the semi-allogeneic fetus and placenta to term. Pregnant women suffering from stress, anxiety, and depression show dysfunctions of their immune system that may be responsible for fetal and/or newborn disorders, provided that placental gene regulation is compromised. The present study explored the effects of maternal chronic self-perceived stress, anxiety, and depression during pregnancy on the expression of immune-related genes and pathways in term placenta. Pregnancies were clinically monitored with the Beck Anxiety Inventory (BAI) and Edinburgh Postnatal Depression Scale (EPDS). A cutoff threshold for BAI/EPDS of 10 divided patients into two groups: Index group (>10, n = 11) and a Control group (<10, n = 11), whose placentae were sampled at delivery. The placental samples were subjected to RNA-Sequencing, demonstrating that stress, anxiety, and depression during pregnancy induced a major downregulation of placental transcripts related to immune processes such as T-cell regulation, interleukin and cytokine signaling, or innate immune responses. Expression differences of main immune-related genes, such as CD46, CD15, CD8α & β ILR7α, and CCR4 among others, were found in the Index group (P < 0.05). Moreover, the key immune-like pathway involved in humoral and cellular immunity named "Primary immunodeficiency" was significantly downregulated in the Index group compared with Controls. Our results show that mechanisms ruling immune system functions are compromised at the maternal-fetal interface following self-perceived depressive symptoms and anxiety during pregnancy. These findings may help unveil mechanisms ruling the impact of maternal psychiatric symptoms and lead to new prevention/intervention strategies in complicated pregnancies.