Human decidua synthesizes placental protein 14 (PP14) in vitro

Human decidua was found to synthesize and secrete placental protein 14 (PP14). The presence of PP14 in tissue explants of decidua, foetal membranes and placenta from term pregnancy was demonstrated by radioimmunoassay. The PP14 content in decidua (1300 +/- 410 ng/100 mg tissue) was higher than in chorion (570 +/- 120 ng/100 mg; P less than 0.01), amnion (240 +/- 100 ng/100 mg; P less than 0.001) or placenta (300 +/- 130 ng/100 mg; P less than 0.001). Three to 36 times more PP14 was released into culture medium by decidual explants compared with the other tissues, and cycloheximide decreased this release by 39%. Placental tissues released hardly any PP14. Decidual synthesis of PP14 was demonstrated by incorporation of [35S]methionine into immunoprecipitable PP14 in tissue culture.