In vitro biosynthesis of human placental lactogen (HPL) by chorionic tissue and the diagnostic value of HPL in trophoblastic disease.

With an aim to elucidate the significance of Human Placental Lactogen (HPL) during gestation, I assayed the HPL and HCG concentration in the chorionic tissue and the blood. The results as follows: 1) There was a definite correlation between the HPL concentration in the maternal serum at term and the weight of the neonates, which might lead to an idea that HPL took part in the growth of fetuses as a metabolic hormone during pregnancy. 2) It was suggested by short term incubation and the cell culture experiment that HPL concentration in the molar tissue was almost the same as or slightly higher than that of the normal chorionic villi, while the serum HPL concentration of molar patient was significantly lower than that of normal pregnant woman. 3) A simultaneous determination of HPL and HCG in serum of trophoblastic disease showed that the HPL/HCG ratio could be useful for differential diagnosis of trophoblastic disease.