A STUDY ON THE HEMOPOI ETIC ACTIVITY OF HUMAN PLACENTA IN VITRO, IN THE PRESENCE AND ABSENCE OF STIMULATORS AND INHIBITORS OF TRANSCRIPTION AND TRANSLATION

The hemopoietic activity of the human placenta was studied in vitrc under various conditions in order to assess the optimal conditions of protein synthesis and colony stimulating factor (CSF) production by this tissue. The hemopoietic activity of placental tissue was assayed by the semi -solid agar medium technique. In order to obtain maximum hemopoietic activity, various stimulators were examined and it was determined that lipopolysaccharide was the most potent stimulator. Inhibitors of transcription and translation were also examined alone and in the presence of stimulators. They potently suppressed hemopoietic activity. Pulse-chase studies with the use of 3H -leucine were used to determine the kinetics of protein synthesis of placental tissue ill vitro.