Abstract: Objective To investigate significance of interferon-γ/interleukin-4(IFN-γ/IL-4) and macrophages in uterus in early embryo loss (or resorption), and to elucidate the anti-abortive effect and the immunological modulation at maternal-fetal interface with quercetin and bornvl acetate. Methods Lipopolysaccharide (LPS)（0.10μg/mouse）was injected via tail vein in order to induce abortion in 7-day-gestation mice which received quercetin and bornvl acetate at days 4-7 of gestation. Levels of IFN-γ and IL-4 in uterus lysate supernatant were measured using enzyme-linked immuno-absorbent assay (ELISA), and uterine macrophages of each group (EM>n/EM>=10) were detected by immunohistochemistry. Results The amount of macrophages was much higher in the uteri of LPSinduced abortion mice than that in control mice. The abortion rate of mouse declined to certain level. The therapy of quercetin combined with bornyl acetate reversed LPS-induced abortion. Conclusion The increase of IFN-γ/IL-4 and the amount of macrophages in the LPStreated mouse uterus is associated with the embryo loss, and que

Key words: Embryo resorption, Lipopolysaccharide, Macrophage, IFN-γ, IL-4, Immunohistochemistry, Mouse