Macrophage Switching in Pregnancy: Regulatory Mechanisms Governing Term Labour and Preterm Birth.

Macrophages play a pivotal role in the immune adaptations required for pregnancy, influencing both term and preterm labour (PTL) through their activation and polarisation. These immune cells originate from the yolk sac, foetal liver, and bone marrow, differentiating into diverse subtypes, including pro-inflammatory (M1) and anti-inflammatory (M2) macrophages. The dynamic transition between these states, termed macrophage switching, is crucial for maintaining pregnancy and orchestrating labour.

Elevated expression and reduced phosphorylation of uterine RIG-I protein in a murine model of pathogenic preterm labor.

In Brief: Preterm labor (PTL) is strongly associated with maternal inflammation, an innate immune response. This study demonstrates that the RIG-I-like receptor (RLR) pathway, a key element of innate immunity, is specifically activated in cases of pathogenic PTL.

Abstract: Unlike TLRs, the regulation of RLRs in PTL is not well understood.