The effect of decidual microenvironment on dendritic cell function in normal pregnancy and abortion

Abstract The present study aimed to investigate the immunomodulatory activity of molecules secreted by decidual cells on dendritic cells (DCs) function in abortion-prone compared with non-abortion-prone mice. The decidual cell supernatants (DS) were obtained from abortion and non-abortion mouse models. DCs were purified from CBA/J mice spleens and treated with antigen and DS. Treated DCs were injected into mice palms. After 5 days، draining lymph nodes were removed، cultured in the presence of cognate antigen، and proliferation of lymphocyte cells was measured by 3H-thymidin incorporation. Our results showed that immunosuppressive activity of DS from non-abortion-prone mice significantly decrease dendritic cells'' ability to stimulate lymphocytes proliferation compared with DS from abortion-prone mice (Simulation index (SI) of 4. 93 ± 0. 34 versus 11. 84 ± 0. 79). We، also found that DS prepared from non-resorption sites compared with DS from resorption sites in abortion-prone mice had increased immunosuppressive activity on DC function (SI of 7. 31 ± 1. 02 versus 2. 67 ± 0. 49). Due to our results، we concluded that immunomodulatory activity of molecules secreted within decidual tissue is different between abortion-prone and non-abortion-prone mice. Based on the key role of DCs in inducing fetomaternal tolerance، we claimed that these molecules، through modulation of DCs function، play crucial role on pregnancy outcome.