Pregnancy-specific beta-1-glycoprotein 1 (PSG1)

Pregnancy-specific beta-1-glycoprotein 1 (PSG1) is a highly glycosylated protein and the most abundantly secreted member of the pregnancy-specific glycoprotein family in humans. It is produced primarily by placental syncytiotrophoblast cells and reaches high concentrations in maternal serum, especially in the third trimester. Structurally, PSG1 is composed of an immunoglobulin variable region-like N-terminal domain and three Ig constant region-like domains. PSG1 is involved in promoting immune tolerance during pregnancy by inducing immunoregulatory cytokines such as TGFB1 and VEGFA in multiple cell types, which can suppress T-cell activity and promote vascular development at the maternal-fetal interface. PSG1 also interacts via its glycan structures with galectin-1 (Gal-1), further modulating immune and vascular processes essential for successful placental development. Abnormal PSG1 expression or glycosylation patterns are associated with pregnancy complications such as preeclampsia and fetal growth restriction. PSG1 is not currently recognized as a therapeutic target for approved drugs, but it serves as a critical biomarker in obstetric medicine[1][2][3].

Other names

B1G1PSBG1PSGGACD66fPS-beta-G-1PSBG-1FL-NCA-1/2PS-beta-C/DPBG1PSG95PSGIIASP1CD66 antigen-like family member Ffetal liver non-specific cross-reactive antigen 1/2pregnancy-specific B-1 glycoprotein