Pathogenic microbes have evolved diverse strategies to invade the host, avoid the innate immune response and multiply. The invasion of human cells by pathogens is observed in food-borne illnesses caused by Salmonella, Shigella and Listeria as well as periodontal (gum) infections. Microbial invasion of host cells is largely achieved by the pathogens' usurping of host signaling pathways. A common target of pathogens is the host cell's actin cytoskeleton, which the microbes use for attachment, entry into cells, movement within and between cells and avoidance of phagocytosis.
The actin-binding protein IQGAP1 is an established regulator of normal cytoskeletal function and may play a role in the invasion of human cells by microbial pathogens. My laboratory is presently investigating the IQGAP1-mediated mechanisms by which Salmonella subverts the actin cytoskeleton to establish infection.