Michel Desjardins is a full professor in the department of pathology and cell biology at the University of Montreal. His main interest is studying immune mechanisms at the cellular level. His recent work has provided the first direct evidence that autoimmune mechanisms mediated by T cells play a role in the induction of Parkinson’s disease (PD) in a mouse model. His laboratory was able to show that LRRK2, a protein associated with PD, is a key regulator of both the innate and adaptive immunity, acting in close interaction with the inflammation-inducing cGAS-STING pathway. Autoimmune mechanisms, including the long-lasting activation of cytotoxic T cells, may explain PD’s extended prodromal period. The work of Dr. Desjardins highlights the potential of developing immune-based therapeutic approaches to slow or prevent PD.