Effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the immune system maternal-fetal interface during palatal development

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is an important environmental pollutant that disturbs the immune balance of the maternal-fetal interface (MFI) and is also a common environmental factor for the formation of cleft palate (CP). Therefore, the purpose is to investigate whether TCDD can cause CP by disrupting the immune balance of the maternal-fetal interface. Fifteen C57BL/6J mice were randomly assigned to three groups: control group, TCDD group, and TCDD plus Freund's complete adjuvant (FCA) (TCDD + FCA) group. Peripheral blood, placentas, and palatal tissues were collected for H&E, flow cytometry, and ELISA. In the TCDD group, the placental diameter, the number of placental labyrinth vessels, and the area of sponge layer cells were all significantly reduced. At embryonic day (E) 17.0, there was a significant decrease in T-helper 1 (Th1) and Th2 cells in the peripheral blood of pregnant mice. Additionally, the levels of interferon-γ (IFN-γ) and interleukin-4 (IL-4), particularly IL-4, were significantly decreased. However, after treatment with FCA, the distance between the palatal shelves was reduced, and the placental weight, the number of labyrinth vessels, and the area of the cavernous cells in the placenta also increased. The number of Th1 and Th2 cells significantly increased, returning to the levels observed in the control group, with a more pronounced increase in the number of Th2 cells. In conclusion, TCDD may induce CP by disrupting the homeostasis of the MFI. The precise mechanisms by which TCDD impacts the immune system at the MFI require further investigation.2,3,7,8-- （TCDD） ， （MFI） ， （CP） 。， TCDD CP。 15 C57BL/6J 3 ：、TCDD TCDD （FCA） （TCDD + FCA） 。、 H&E、 ELISA。TCDD 、。 17.0 （E） ， T 1 （Th1） Th2 。，-γ （IFN-γ） -4 （IL-4）， IL-4 。， FCA ，，、。Th1 Th2 ，，Th2 。，TCDD MFI CP。TCDD MFI 。.