title: Endothelin-1 and macrophage colony-stimulating factor are co-localized in human amnion membrane cells and secreted into amniotic fluid.
abstract: We have examined the cellular localization and human amniotic fluid content of endothelin-1 (ET-1) and macrophage colony-stimulating factor (M-CSF). The study material consisted of amniotic fluid from 20 patients referred for amniocentesis, and placental samples from normal deliveries. ET-1 and M-CSF were analysed by radioimmunoassay and enzyme-linked immunosorbent assay respectively. The cellular localization of ET-1 and M-CSF in the amnion membranes was analysed by double-labelling immunocytochemistry using fluorescein isothiocyanate- and Cy3-labelled secondary antibodies. Release of ET-1 and M-CSF was studied in cultured amniocytes. We found that the mean +/- SD concentrations of ET-1 and M-CSF in fetal amniotic fluid were 45.6 +/- 17.3 pmol/l (range 16.8-85.5) and 7323 +/- 3415 ng/l (range 2640-12 110) respectively. Double-labelling immunocytochemistry showed that both M-CSF and ET-1 were co-localized in the same cells to a high extent. Further analysis revealed that levels of M-CSF, but not ET-1, were significantly correlated with pregnancy length. Both M-CSF and ET-1 were released from cultured amniocytes in response to interleukin-1. These findings show that ET-1 and M-CSF are partly co-localized to specific cells in the human amniotic membrane. As both M-CSF and ET-1 were released from cultured amniocytes in vitro, this suggests that they both may be secreted into fetal amniotic fluid in vivo as well.
authors.affiliation: Department of Woman and Child Health, Division of Obstetrics and Gynecology, Karolinska Institute, S-171 76 Stockholm, Sweden. gabriel.fried@kbh.ki.se
authors.forename: Gabriel
authors.initials: G
authors.lastname: Fried
authors.forename: Anna
authors.initials: A
authors.lastname: Sand
authors.forename: Eva
authors.initials: E
authors.lastname: Ostlund
authors.forename: Eva
authors.initials: E
authors.lastname: Andersson
authors.forename: Birgitta
authors.initials: B
authors.lastname: Byström
authors.forename: Berit
authors.initials: B
authors.lastname: Ståbi
mesh_terms: D000293:Adolescent; D000328:Adult; D000650:Amnion / Q000737:chemistry* / Q000166:cytology; D000653:Amniotic Fluid / Q000737:chemistry* / Q000166:cytology; D001724:Birth Weight; D005314:Embryonic and Fetal Development; D019332:Endothelin-1 / Q000032:analysis* / Q000378:metabolism*; D005260:Female; D006801:Humans; D016173:Macrophage Colony-Stimulating Factor / Q000032:analysis* / Q000378:metabolism*; D011247:Pregnancy; D011264:Pregnancy Trimesters
chemical_list: D019332:Endothelin-1; D016173:Macrophage Colony-Stimulating Factor