Characterizing Biomarkers of Early Parkinson's Disease Progression (TREG)

Objectives: Parkinson's disease is the second most common neurodegenerative condition worldwide, and while both motor and non-motor symptoms can be improved with symptomatic therapies, there are currently no drugs that slow or halt progression of the disease. All previous trials of neuroprotective therapies have failed, in large part due to the lack of objective, sensitive biomarkers of Parkinson's disease progression. Plan: The proposed study aims to characterize the rate of change in a peripheral blood marker of inflammation (Treg percentage) and three quantitative motor measures (finger tapping, 9-hole peg test and peak turn velocity) in a cohort of 25 untreated PD patients with motor testing and blood sampling performed at baseline and at 6 months Methods: Participants will have three visits to the Portland VA over a 12 month period. Assessments will be made regarding their Parkinson's disease progression (motor ability and gait and balance). At each visit, a VA phlebotomist will draw whole blood. The VA lab will analyze whole blood for metabolic CBC with differential. The research team will hand carry blood samples from the VA phlebotomist to Dr. Quinn's VA lab in BLDG 103 - E143. A plasma sample will be added to the Neurologic Disorders Repository (MIRB # 3129). Peripheral blood mononuclear cells (PBMC) will be isolated from buffy coats using Ficoll-Paque. The PBMC will be frozen and batch analyzed for T lymphocytes using flow cytometry at OHSU.