Grant: Operating Grant

Cells in the body travel continuously through the blood vessels ready to seed new tissues replacing older cells in blood cell formation or to repair injury or defend against infectious agents in immune response. If an infection occurs many different cells are mobilised to fight the infectious agents. Some of these cells (dendritic cells) will ingest bacteria or virus at the site of infection and then travel to centres in the body (the lymph nodes) that are designed to instruct lymphocytes to fight the invading infectious agents. Lymphocytes continuously enter lymph nodes where they interact with the dendritic cells. If they encounter dendritic cells that have ingested an infectious agent that matches their receptor the lymphocytes become activated and multiply in the lymph node. (This is the reason that the area under the chin becomes swollen when people have a sore throat). In order to fight the infectious agents these activated lymphocytes need to receive directions where to go. To this end, dendritic cells also induce specific antennae shaped homing receptors on the lymphocytes surface that will then direct them to enter the inflamed tissues that bind these antennae. There are several ways for lymphocytes to regulate these antennae. The cells can stop expression of the antennae or express functional/non-functional antennae by adding or removing sugar molecules that are attached to these antennae. We are interested in understanding the signals and mechanisms that alter the sugar molecules on these antennae and thus program directions into immune cells.