Host cell protein impurities modify the immunomodulatory profile of pregnancy-specific glycoprotein 9, a cautionary tale
IntroductionPregnancy-specific glycoprotein 9 (PSG9) is one of 10 members of a conserved glycoprotein family within the carcinoembryonic antigen superfamily expressed by placental trophoblasts and secreted into maternal circulation. PSG1 and PSG9 induc…