Role of LRRK2 in immunity in a nonhuman primate model of SIV - Project Summary While modern therapy has enabled the more than 37 million people living with HIV to experience near normal life expectancy and transformed it into a manageable chronic disease, neurocognitive impairment remains an unresolved clinical concern. Increasing evidence indicates that chronic systemic immune activation contributes to neuroinflammation, and neuroinflammation promotes the severity of neurodegenerative diseases. Intriguingly, viral-induced neuroinflammation has striking similarities to neurodegenerative disease, and chronic infection may increase the risk of developing neurodegenerative disease. One factor linked to neuroinflammation, neurodegeneration, and host immunity against microbial pathogens is the immune kinase leucine rich repeat kinase 2 (LRRK2). LRRK2 has been implicated in modulating antiviral cytokine activity, conferring susceptibility to mycobacterial infection, and mutated LRRK2 is the most common monogenetic cause of the neurodegenerative disorder Parkinson’s disease. The long-term objectives of this proposal are to extend the observation that LRRK2 modulates antiviral immunity during bacterial infection to determine the function of LRRK2 in viral pathogenesis and neuroinflammation and assess its therapeutic potential. Using a macaque SIV infection model for HIV, this proposal seeks to address the fundamental questions of whether SIV infection promotes LRRK2 expression, and how loss of LRRK2 impacts SIV pathogenesis and the host immune response. We hypothesize that LRRK2 contributes to HIV pathogenesis through regulation of antiviral immunity. To test this, we will use a non-human primate (NHP) model to assess the impact of SIV infection on LRRK2 gene expression and protein levels longitudinally in circulating immune populations and gastrointestinal tract, and at a single time point in the brain as LRRK2 is dynamically expressed in these tissues. Next, we will assess the impact of LRRK2 inhibition on host response to SIV using both in vivo and ex vivo approaches. The data obtained by this project will shed light on the function of LRRK2 in antiviral immune activation and generate preliminary data for future studies investigating factors contributing to viral-induced neuroinflammation. The proposed study and Mentored Career Development Plan will be conducted at Tulane National Primate Center (TNPRC) under the guidance of Drs. Tracy Fisher and Ronald Veazey, experts in viral induced neuroinflammation and SIV pathogenesis. The TNPRC is a national resource for NHP biomedical research with a long history of research excellence in viral pathogenesis and therapeutic intervention. The TNPRC has a strong commitment to training and mentorship demonstrated by extensive financial, effort- based, and programmatic support to cultivate a rich and diverse training environment for early-stage investigators. The mentored support and dedicated time provided by the K01 will further Dr. Vail’s career goals of becoming an independent investigator and NHP researcher studying host pathogen interactions.
