PSG5 Human

Pregnancy Specific Beta-1-Glycoprotein 5 (PSG5) is a member of the pregnancy-specific glycoproteins (PSGs), which are a subgroup of the carcinoembryonic antigen (CEA) family within the immunoglobulin superfamily . These glycoproteins are primarily produced by the placental syncytiotrophoblasts during pregnancy and play a crucial role in modulating the maternal immune system .

PSG5 is a secreted protein that contains two Ig-like C2-type (immunoglobulin-like) domains and one Ig-like V-type (immunoglobulin-like) domain . The protein-coding gene for PSG5 is located on chromosome 19 . PSGs, including PSG5, are among the most abundant fetal proteins found in maternal blood during pregnancy . They are believed to help in avoiding the rejection of the semiallogeneic fetus by the maternal immune system and facilitate the access of trophoblast cells to maternal resources via the blood system .

PSGs have evolved rapidly, and their presence correlates with hemochorial placentation in primates . In humans, there are 10 PSG genes that encode closely related secreted glycoproteins . These genes are exclusively expressed in fetal syncytiotrophoblast cells . The rapid evolution of PSG genes is thought to optimize fetal-maternal interactions and possibly pathogen interactions in mammals with intimate contact of fetal cells with the maternal immune system .

PSG5, like other PSGs, has been associated with various diseases. For instance, it has been linked to irritant dermatitis and X-linked agammaglobulinemia . Additionally, PSGs are involved in pathways such as the response to elevated platelet cytosolic Ca2+ and cell surface interactions at the vascular wall .

Human recombinant PSG5 is produced using recombinant DNA technology, which allows for the production of the protein in a controlled environment. This recombinant form is used in various research and clinical applications to study its function and potential therapeutic uses.