Increased levels of macrophage colony-stimulating factor in the placenta and blood in preeclampsia

PROBLEM: Macrophage colony-stimulating factor (M-CSF) is considered an essential cytokine for placental growth and maintenance. We evaluated whether M-CSF levels in the placenta and blood in preeclampsia differed from those in normal pregnancies. METHOD OF STUDY: The subjects were 37 pregnant women carrying single fetuses, of whom 19 were women with normal pregnancies and 18 were women with precclampsia. Their average gestational age at entry was 38 weeks of gestation. Blood was collected before the onset of labor, and separated serum was obtained after centrifugation. A tissue segment of the placenta was cut immediately after delivery. The frozen placental tissue was placed in a plastic tube containing phosphate-buffered saline. The tissue was fully homogenized and then centrifuged. Separated supernatant was used for subsequent determination. M-CSF levels in separated serum were measured, and M-CSF and total protein (TP) levels in separated supernatant were also measured. RESULTS: Both M-CSF/TP levels in the placenta and M-CSF levels in blood were significantly higher (P < 0.05-0.01) in preeclampsia than in normal pregnancies. CONCLUSIONS: This is the first report concerning high placenta levels of M-CSF/TP in preeclampsia. Increased M-CSF in the placenta supports the hypothesis that immunological abnormalities contribute to the etiology of preeclampsia.