Decreased placental IL9 and IL9R in preeclampsia impair trophoblast cell proliferation, invasion, and angiogenesis.

<bold>Objective: </bold>Our study aimed to investigate IL9 and IL9R expression in preeclampsia and assess their effects on trophoblast biological behaviors.<bold>Methods: </bold>IL9 and IL9R expression of placenta tissue were evaluated by immunochemistry and q-PCR. Using transwell, CCK-8, and tubule formation assays measured invasion, proliferation and angiogenesis of trophoblast with adding IL9 or anti-IL9R antibody.<bold>Results: </bold>IL9 and IL9R levels were significantly decreased in preeclampsia. IL9 improved trophoblast activities. Blocking IL9/IL9R resulted in decreased proliferation, invasion, and tube-formation capability of trophoblast.<bold>Conclusions: </bold>IL9 and IL9R contribute to the pathogenesis of preeclampsia. IL9/IL9R signaling provides a new potential therapeutic target for preventing preeclampsia. [ABSTRACT FROM AUTHOR]