Effects of Cytokines and TLR Ligands on the Production of PlGF and sVEGFR1 in Primary Trophoblasts.
Cytokines such as tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) play an important role in maintaining pregnancy. Toll-like receptors (TLRs) have also been associated with innate immune responses during pregnancy. Placenta growth factor (PlGF) is one of the angiogenic factors and soluble vascular endothelial growth factor receptor 1 (sVEGFR1) is one of the antiangiogenic factors that regulate PlGF function. To elucidate the effects of cytokines and TLR ligands on the production of angiogenic and antiangiogenic factors in trophoblasts, we examined the production of PlGF and sVEGFR1 from trophoblasts following stimulation with cytokines and TLR ligands. Villous tissues were obtained from healthy pregnant women who had had an artificial abortion. The trophoblasts were isolated from villous tissues. Subsequently, trophoblasts were treated with TNF-α, IFN-γ and TLR ligands. The levels of PlGF and sVEGFR1 were measured by enzyme-linked immunosorbent assay. The expression of those mRNA was analyzed using quantitative reverse transcription PCR. The production of PlGF in trophoblasts increased by the addition of TNF-α or IFN-γ and decreased by TLR4 ligand. sVEGFR1 levels also increased by following the stimulation with IFN-γ or TLR ligand. Cytokines such as TNF-α and IFN-γ and TLR ligands may contribute to the production of angiogenic and antiangiogenic factors and may affect the placental formation.