Decoding the chemokine network that links leukocytes with decidual cells and the trophoblast during early implantation

Abstract

Chemokine network is central to the innate and adaptive immunity and entails a variety of proteins and membrane receptors that control physiological processes such as wound healing, angiogenesis, embryo growth and development. During early pregnancy, the chemokine network coordinates not only the recruitment of different leukocyte populations to generate the maternalplacental interface, but also constitutes an additional checkpoint for tissue homeostasis maintenance. The normal switch from a pro-inflammatory to an anti-inflammatory predominant microenvironment characteristic of the post-implantation stage requires redundant immune tolerance circuits triggered by key master regulators. In this review we will focus on the recruitment and conditioning of maternal immune cells to the uterus at the early implantation period with special interest on high plasticity macrophages and dendritic cells and their ability to induce regulatory T cells. We will also point to putative immunomodulatory polypeptides involved in immune homeostasis maintenance at the maternal-placental interface.

The role of CXC chemokine ligand 16 in physiological and pathological pregnancies

“…CXCL16 expression has been reported in the decidual stroma cells (DSCs) during the first-trimester. 20,21,25 However, the transcription and translation levels of CXCL16 do not appear to be completely consistent. A study by Huang et al explored the transcription levels of CXCL16 in the DSCs using reverse transcription-polymerase chain reaction (RT-PCR), and the transcription level of CXCR6 was shown to be markedly higher compared with that of CXCL16.…”

“…Furthermore, the expression of CXCR6 was also detected in trophoblasts . Moreover, primary cultured trophoblast cells were shown to secrete high levels of CXCL16 during the first‐trimester . However, no published studies have yet investigated CXCL16 expression in the second or third trimester of pregnancy.…”

“…CXCL16 expression has been reported in the decidual stroma cells (DSCs) during the first‐trimester . However, the transcription and translation levels of CXCL16 do not appear to be completely consistent.…”

“…19,20 Moreover, primary cultured trophoblast cells were shown to secrete high levels of CXCL16 during the first-trimester. [20][21][22]24 However, no published studies have yet investigated CXCL16 expression in the second or third trimester of pregnancy. These results may indicate that CXCL16 mainly regulates maternal and fetal immunity in early pregnancy.…”

Control of the inflammatory response during pregnancy: potential role of VIP as a regulatory peptide

“…Uterine natural killer cells (uNKs), monocytes, macrophages, dendritic cells, T lymphocytes, and neutrophils are found in the pregnant uterus at different stages throughout gestation . A network of chemokine receptors expressed on blood leukocytes and chemokines released by trophoblast and stromal cells underlie the sequential waves of immune cell populations attracted to the interface . These leukocyte populations handle the varying demands of pregnancy with a space and temporal pattern.…”