Immunology in Pregnancy: The Mechanism behind Immune Tolerance

The immune system in humans is a complex system which is capable of discriminating the selfantigen from the non - selfantigens and thereby mounting an appropriate allogenic immune response against the foreign antigens. Pregnancy is not an immunodeficient state. Whereas a successful organ transplant requires constant immunosuppression, a successful pregnancy requires a robust, dynamic and responsive immune system. Women are able to respond to both humoral and cell mediated immunity against the paternal antigen. During pregnancy, the maternal immune response is shifted from Th1 (cell mediated immunity) to Th2 (humoral immunity) response. This change in immune response is known as immunomodulation. Interferon - ? is a crucial immune modulator during pregnancy; it protects the fetus against viral infections and contributes to the process of immune regulation at the maternal?fetal interface. During pregnancy, the development of a fetal immunological system also occurs with intricate interaction between the maternal and fetal interface.