Different factors influencing immune adaptation during pregnancy
Different factors influencing immune adaptation during pregnancy
Pregnancy requires the maternal immune system to adapt in order to tolerate the semi-allogeneic fetus while maintaining protection against pathogens. This thesis of Anne Laskewitz investigated how various factors shape maternal immune adaptation, focusing on fetal semi-allogeneity, parity, the maternal microbiome, fetal sex, and maternal obesity, using both mouse models and human studies.
Mouse studies demonstrated that fetal allo-antigens have only a minor role in driving immune changes during mid and late pregnancy, suggesting they fine-tune rather than initiate maternal immune adaptation. In contrast, parity had a clear impact: second pregnancies showed tissue-specific alterations in T cells and regulatory T cells, supporting the concept of long-lasting immunological memory that may reduce the risk of complications. The maternal microbiome was also found to influence memory T cell populations during pregnancy in a tissue-specific manner.
Human studies revealed that multigravida women exhibit a more activated and immunoregulatory immune profile in the decidua compared to primigravida women. Additionally, fetal sex was associated with differences in early pregnancy immune gene expression, and maternal obesity affected decidual macrophage subsets, possibly reflecting compensatory mechanisms for a pro-inflammatory state.
Overall, this thesis shows that maternal immune adaptation is largely driven by pregnancy itself, while factors such as parity, microbiome, fetal sex, and obesity modulate these processes. These findings provide important insights into the mechanisms underlying healthy pregnancy and immune-related complications, and may contribute to improved diagnosis and intervention strategies.