The characterization of fibrocyte-like cells: a novel fibroblastic cell of the placenta.
The placenta is a highly vascularized organ thus angiogenesis is a key process in placental development. The contribution that different cells in the villous stroma play in placental angiogenesis is largely unknown. In this study we identified a novel stromal cell type in sections of term placenta which is morphologically fibroblastic and expressing the fibroblast marker TE-7 but also positive for the monocytic markers CD115 and CD14 and designated these cells as fibrocyte-like cells. Populations of fibrocyte-like cells from the placenta were isolated by two methods: culture of adherence-selected placental cells and, for higher purity, by CD45 fluorescence activated cell sorting (FACS). Fibrocyte-like cell conditioned medium increased endothelial tubule-like structure formation 2-fold versus control medium. Both pro-angiogenic growth factors vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (b-FGF) and the anti-angiogenic factor soluble-Flt were found in the conditioned medium. Neutralizing antibodies against VEGF and b-FGF reduced endothelial cell tubule-like structures to control levels. These data suggests that fibrocyte-like cells, a previously unidentified cell of the villous stroma, may play an important role in the regulation of placental angiogenesis.
Department of Physiology, University of Alberta, Edmonton, Canada T6G 2S2.
M R
MR
Riddell
B
B
Winkler-Lowen
S
S
Chakrabarti
C
C
Dunk
S T
ST
Davidge
L J
LJ
Guilbert
D002469:Cell Separation / Q000379:methods; D002478:Cells, Cultured; D002824:Chorionic Villi / Q000378:metabolism / Q000502:physiology; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000166:cytology* / Q000502:physiology*; D005434:Flow Cytometry; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D008264:Macrophages / Q000378:metabolism / Q000502:physiology; D009000:Monocytes / Q000378:metabolism / Q000502:physiology; D018919:Neovascularization, Physiologic / Q000502:physiology; D010920:Placenta / Q000098:blood supply / Q000166:cytology* / Q000502:physiology; D011247:Pregnancy; D061251:Primary Cell Culture