Type III interferons in immunity against bacteria

Cells of the immune system secrete proteins called interferons (IFNs) when they communicate. I study IFNs of the type III family (IFNλs) that are important regulators of intestinal immunity. I have found that IFNλs are produced in response to infection with intestinal bacteria such as Salmonella, Shigella and E. coli. I also found that mice that do not have an IFNλ system are unable to fight Salmonella infection as efficiently, and that IFNλs protect the intestinal barrier from damage inflicted by bacteria. Pathogenic bacteria have also devised virulence mechanisms to block IFNλ production. My findings suggest that type III IFNs are indeed important for our immune system to fight bacterial infections.

I will study this in greater detail by examining how IFNλs block bacterial growth in infected animals and infected cells. I will also identify how host cells produce IFNλs in response to bacterial components. I aim to identify the bacterial factors that pathogenic bacteria use to block IFNλ expression and signalling.

This project will advance our understanding of intestinal immunity and how some bacterial pathogens cause disease by interfering with this aspect of the immune system.