Dr. Philpott has a long-standing interest in host-pathogen interactions and innate immunity. In 2003, her team discovered that members of an intracytosolic family of innate immune receptors, called Nod1 and Nod2, detected peptidoglycan from the bacterial cell wall. Nod2 was the first susceptibility gene linked to an inflammatory bowel disease, i.e, Crohn’s disease (CD). Her laboratory uncovered that defective peptidoglycan sensing was linked to CD-associated mutations in Nod2. She has recently become interested in the Parkinson disease (PD)-related protein, LRRK2. Interestingly, the gene encoding LRRK2 has also been implicated in CD susceptibility as well as leprosy. Through collaborations with Dr. Michael Schlossmacher, the Philpott laboratory begun to study the role of this protein in innate immune defense. Our main objective is to explore the potential link of LRRK2 with innate immune regulation to infection as a novel angle towards understanding the role of LRRK2 in PD pathogenesis.