[Placental-renal prealbumin: immunochemical identification, physico-chemical characteristics and affinity...

A protein with prealbumin mobility and MW of 40 kD was identified in early placental tissue. Using immunodiffusion analysis the protein was also detected in fetal and adult kidney tissues, in urine of donors and pregnant women and in amniotic fluid. The protein was termed placenta-kidney prealbumin (PKPA). During affinity chromatography on immobilized steroid hormones, PKPA was bound to testosterone and was not bound to diethylstilbestrol.