The immune response is the set of defenses our bodies mount to counter harmful microbes. The innate immune response is our first line of defense, providing protection until the adaptive immune response is activated. Unfortunately, the innate immune response can also be a double-edged sword. It can spin out of control and cause an overwhelming immune response called sepsis, which is responsible for 200,000 deaths every year in the US. The innate immune response is initiated and regulated by complex signalling pathways of genes in our cells. These pathways identify which type of microbe is invading (bacteria or viruses, for example) and mounts appropriate responses. Dr. David Lynn is investigating the genes involved in the innate immune response, how they are turned on and off in particular infections, and what goes wrong in cases of sepsis. This work generates vast quantities of data, requiring computer-based approaches (bioinformatics) to understand and handle such large datasets. Lynn’s work integrates gene expression data with information about how genes and proteins are interconnected in our cells in signalling networks or pathways – providing new information about gene interconnections influence their regulation. He is also investigating the same networks and pathways in other species such as mouse and cow, determining the differences and similarities in their innate immune response. Lynn’s work will help identify potential therapeutic or drug targets that could help safely boost the immune response. It will also highlight cases where important immunological differences make animal models unsuitable for research on human immunity.