Production of granulocyte colony stimulating factor in decidual tissue and its significance in pregnancy.

The increase of the number of polymorphonuclear leukocytes (PMN) in peripheral blood during pregnancy is well known. Granulocyte colony stimulating factor (G-CSF) has been found to act as a hemopoietic factor for PMN. This study analyzed G-CSF concentrations in the peripheral blood of pregnant women and examined whether decidual tissue acted as source of G-CSF production. The proliferation of chorionic cells measured by [3H]-thymidine uptake and its association with G-CSF were also examined. The results revealed that the concentration of G-CSF increased during the course of pregnancy and was positively correlated with the number of PMN. Large amounts of G-CSF was produced in cultures of decidual cells. We also found that G-CSF stimulates the proliferation of the chorionic cells. It was concluded that the decidual cells have a G-CSF producing activity associated with the elevation of PMN and play some role in the proliferation of chorionic cells during pregnancy.