Reproductive immunology seeks to understand how the maternal immune system supports pregnancy while maintaining the ability to fight infection. The field traces its origins to Sir Peter Medawar’s 1953 observation that pregnancy, where a genetically distinct conceptus (fetus and placenta) thrives within an immunocompetent mother, seems to defy classical rules of immune rejection. Although his original hypotheses have been revised, they set the stage for decades of discoveries showing the remarkable complexity of so-called “fetomaternal tolerance”.
Modern work shows that maternal immune cells do in fact interact intimately with placental and fetal antigens, and that placental cells express many antigens that are foreign to the maternal immune system. Yet, unlike transplanted organs or mutated tumor cells, the conceptus is not rejected. Instead, multiple tolerance pathways, operating systemically and at the maternal-fetal interface, restrain pathogenic B and T cell responses while largely preserving immunity to pathogens. This balance allows the mother to remain protected while nurturing a genetically distinct conceptus.
Across our center, laboratories study diverse facets of reproductive immunology, including maternal tolerance to seminal fluid, placental, and fetal antigens; how immunity to self and foreign antigens is reshaped during pregnancy; and how dysregulated maternal immune responses contribute to pregnancy complications.
