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Exosome LRRK2 in Predicting Parkinson's Disease Phenotypes (U01)

Andrew West, Ph.D.
PI:
Andrew West, PhD
University of Alabama (Birmingham, Alabama)

Summary

Over the last several years, Dr. West’s laboratory has identified that levels of pS1292-LRRK2 isolated from urine and CSF exosomes are predictive of the risk for Parkinson’s Disease (PD) in G2019S-LRRK2 carriers, as well as the severity of the disease in idiopathic PD patients.  This project will focus on whether measurements of exosomal isolated pS1292-LRRK2 can act as a diagnostic and/or prognostic biomarker for LRRK2 mutation carriers and idiopathic PD cases.  Preliminary data indicate that pS1292-LRRK2 may be a prognostic biomarker for idiopathic PD in regards to the rate of cognitive decline in mid to late PD cases and in regards to the rate of early motor symptom development and time to L-dopa medication in de novo cases.  This project will utilize biosamples and clinical data associated with the LRRK2 Cohort, the JHMI PDBP study and the MJFF PPMI study.

Study Information

Title: LRRK2 and Other Novel Exosome Proteins in Parkinson's Disease
PI Name: Andrew West
Repository: Parkinson's Disease Biomarker Program
Status: Controlled Access
Funding Source: NIH-NINDS
Abstract: University of Alabama, Birmingham, AL; 1U18 NS082132-01; Dr. West's lab has made the recent observation that LRRK2, and other proteins linked genetically and pathologically to PD, are detectable in exosomes isolated from human urine samples. Using a multiplex mass spectrometry approach, they can quantify 935 proteins from clinical urine exosome samples, and 140 of these proteins are linked to neurodegeneration by pathway analysis. This study seeks to 1) determine whether there are biomarkers associated with PD susceptibility and/or progression in urinary exosome-proteomes derived from PD patients versus controls, and 2) to determine if LRRK2 expression and/or phosphorylation are significantly lowered in the urinary exosomes of individuals treated with the potent LRRK2 kinase inhibitor sunitinib (a multi-kinase inhibitor compound), to establish an assay for on-target effects for future LRRK2 inhibitor clinical trials. Potential biomarkers of interest will be validated in a replication cohort, and the most promising leads will be further explored in future multi-center studies. The study will enroll 300 PD cases and 300 age-matched healthy controls. Clinical assessment will include the core baseline visit for PDBP and both DNA and RNA samples will be collected at the baseline visit and distributed through the NINDS repository. # of subjects planned for enrollment: 600 Patient inclusion criteria: Inclusion criteria will be based on UK Brain Bank criteria for the clinical diagnosis of PD, and will require: 1) the presence of bradykinesia and either rest tremor or rigidity; 2) asymmetric onset; 3) progressive motor symptoms 4) age at onset 35-85 years. Control inclusion criteria: ages of between 35-85 years, a lack of PD in first-degree blood relatives, and a lack of positive responses on more than 3 items on the PD Screening Questionnaire. # of PD participants: 300 # of Controls: 300 # of other diagnoses (specify): N/A Clinical Assessments: 1 visit type (baseline) is collected Baseline visit ? Behavioral History, Demographics, Epworth Sleepiness Scale, Family History, Hamilton Anxiety Rating Scale (HAM-A), Hamilton Depression Rating Scale (HDRS), Informed Consent and Enrollment, MDS-UPDRS (Movement Disorder Society - Unified Parkinson's Disease Rating Scale), Modified Schwab and England Activities of Daily Living Scale, Montreal Cognitive Assessment (MoCA), Neurological Exam, PDBP Inclusion and Exclusion Criteria, PDQ-39, Prior and Concomitant Medications, Rapid Eye Movement Behavior Disorder Questionnaire, University of Pennsylvania Smell Identification Test (UPSIT) and Vital Signs Types of biospecimens: DNA and RNA at baseline visit
Study ID: PDBP-STUDY0000204
Data Type: Clinical Assessment
Study Type: Natural History
Grant ID: U1 8NS082132
Study Started On: 2013-01-15
Study Completed On: 2015-12-19
Estimated number of Subjects: 609

Abstract

There is a critical need for quantitative biomarkers that predict Parkinson disease (PD) susceptibility and progression. Such biomarkers would aid the development of new therapies that slow or halt disease. PD has a clear genetic component that contributes to disease susceptibility. One gene in particular, leucine-rich repeat kinase 2 (LRRK2), harbors pathogenic missense mutations prevalent in some populations. LRRK2 is further linked to PD susceptibility through genome-wide association studies. Pathogenic LRRK2 mutations upregulate LRRK2 kinase activity and increase levels of the auto phosphorylated residue serine S1292 (pS1292). In our previous project Exploratory Laboratory and Analysis Projects in PDBP (U18 NS082132), we focused our efforts on analyzing and measuring LRRK2 in clinical samples. We discovered that auto phosphorylated LRRK2 (pS1292-LRRK2) could be detected and quantified in exosome fractions from both cerebral-spinal fluid (CSF) and urine. We found elevated levels (~5 fold) of pS1292-LRRK2 in urinary exosomes from G2019S-LRRK2 mutation carriers with PD. In G2019S-LRRK2 mutation carriers, pS1292-LRRK2 levels successfully predicting clinical PD manifestation. We further analyzed pS1292-LRRK2 in a large cohort of cases and controls (n=160) from the University of Alabama at Birmingham Parkinson's Disease Biomarker Program (UAB PDBP) and found that pS1292-LRRK2 levels predicted PD phenotypes in patients. Here we will determine the potential of exosome pS1292-LRRK2, purified from urine and CSF, in predicting PD susceptibility and progression in both early and mid-stage idiopathic PD cases as well as in LRRK2 mutation carriers. Project success will include the discovery of novel insights into the role of LRRK2 in the pathogenesis of PD and the development of a novel biomarker (exosome pS1292-LRRK2) that may predict PD manifestation in LRRK2 mutation carriers. The successful prediction of LRRK2 mutation carriers that will go on to develop PD would aid in future clinical trial design for LRRK2-directed therapies. Finally, we predict that the novel biomarker exosome pS1292- LRRK2 may help stratify idiopathic PD patients that will experience rapid progression of PD symptoms from those with more benign disease courses. Identification of PD cases with a poor prognosis would assist physicians in making treatment choices and clinical trial design for novel neuroprotective therapies.

Goals

Goals of this project:

1. Isolation of exosomes from urine and CSF samples from the LRRK2 cohort and measurement of pS1292-LRRK2 levels using Western blot analysis.

2. Isolation of exosomes from urine and CSF samples from the JHMI PDPB cohort (cross-sectional and longitudinal) to determine if levels of pS1292-LRRK2 correspond to PD non-motor disease severity.

3. Determine if western blot analysis using LRRK2 mouse monoclonal N241A/34 (Antibodies Inc), and pS1292-LRRK2 rabbit monoclonal (Abcam MJFR-19 LRRK2) can be developed into a SiMoA assay in collaboration with Dr. David Walt.  
 

Andrew West, Ph.D.