Understanding the innate immune system is essential for the development of new therapies for the treatment of microbial infection, the management of autoimmune disorders and the provision of protective immunity via vaccination. My group investigates two members of the intracellular NOD-like receptor family, NOD1 and NOD2. These proteins are activated by fragments of bacterial peptidoglycan; γ-D-glutamyl-meso-diaminopimelic acid for NOD1 and muramyl dipeptide for NOD2.