Decidual glycodelin-A polarizes human monocytes into a decidual macrophage-like phenotype through Siglec-7.

Decidual macrophages constitute 20-30% of the total leukocytes in the uterus of pregnant women, regulating the maternal immune tolerance and placenta development. Abnormal number or activities of decidual macrophages (dMs) are associated with fetal loss and pregnancy complications, such as preeclampsia. Monocytes differentiate into dMs in a decidua-specific microenvironment.

Soluble human leukocyte antigen G5 polarizes differentiation of macrophages toward a decidual macrophage-like phenotype.

Study Question: What are the actions of soluble human leukocyte antigen G5 (sHLAG5) on macrophage differentiation?

Summary Answer: sHLAG5 polarizes the differentiation of macrophages toward a decidual macrophage-like phenotype, which could regulate fetomaternal tolerance and placental development.

What Is Known Already: sHLAG5 is a full-length soluble isoform of human leukocyte antigen implicated in immune tolerance during pregnancy. Low or undetectable circulating level of sHLAG5 in first trimester of pregnancy is associated with pregnancy complications such as pre-eclampsia and spontaneous abortion.

Adrenomedullin enhances invasion of human extravillous cytotrophoblast-derived cell lines by regulation of urokinase plasminogen activator expression and s-nitrosylation.

Extravillous cytotrophoblast (EVCT) is responsible for trophoblast invasion, which is an important process during placentation. Dysregulation of the process is associated with a wide range of pregnancy complications. Adrenomedullin (ADM) is a polypeptide expressed most abundantly in first-trimester placentas.