Two research areas are under investigation. In the first, we are studying mechanisms used by human trophoblast (placental) cells to invade the uterus during pregnancy. Fetal development depends on the embryo's rapidly attaching to the uterus and gaining access to the maternal circulation. The trophoblast cells that form the fetal portion of the human placenta have solved this problem by transiently exhibiting certain tumor-like properties. We are uncovering the adhesive and proteolytic mechanisms that mediate trophoblast invasion, as well as identifying ways these fetal cells avoid maternal immune surveillance. At the same time we are using our knowledge of placental development in normal pregnancy to understand the causes of a common pregnancy complication, preeclampsia. In this life-threatening condition cytotrophoblast invasion is abnormally shallow.

In the second area of research, we are studying adherence mechanisms used by bacteria. Adherence is the important first step in development of an infection. These initial interactions are often mediated by the carbohydrate portions of receptor molecules. We have devised several techniques that allow rapid identification of bacterial receptors in complex glycoprotein mixtures. We then determine, by mass spectrometry, the complete structure of the oligosaccharides that carry the bacterial receptor activity. Recently we showed that a salivary mucin can tether both bacteria and leukocytes, a potentially important mechanism for fighting infection.