Blood-based biomarkers for early detection, diagnosis and staging of Parkinson’s disease

Using human protein microarrays, the researchers identified a panel of blood-borne autoantibodies that act as potential biomarkers to detect early-stage Parkinson's disease with an overall accuracy of 87.9 percent (94.1 percent sensitivity and 85.5 percent specificity), and an accuracy rate of 97.5 percent in differentiating between early and mild-moderate stages of the disease. The researchers also reported that the test demonstrated similar accuracy in distinguishing Parkinson's from Alzheimer's disease (97.0 percent), multiple sclerosis (96.3 percent) and breast cancer (97.5 percent). Their findings appear online in Immunology Letters.

"Currently, there is no simple and reliable diagnostic test for Parkinson's disease," said Robert Nagele, PhD, the director of the Biomarker Discovery Center at Rowan University's New Jersey Institute for Successful Aging and co-founder of Durin Technologies, Inc. "Instead, diagnosis relies on clinical observation of patients' symptoms and is only accurate about three-quarters of the time. An accurate, inexpensive and relatively non-invasive test for early-stage Parkinson's could have a profound impact that leads to earlier treatment of patients and allows for early enrollment of patients into clinical trials."

"As more potentially disease-modifying therapies move to clinical testing, the need for a Parkinson's biomarker grows more urgent," said Catherine Kopil, PhD, senior associate director of research programs at The Michael J. Fox Foundation for Parkinson's Research, which partially funded the study and provided biospecimens for analyses. "The abilities to identify subjects at early stage of disease and to measure impact of therapeutics would improve our likelihood of successful intervention, and Dr. Nagele's work is a step in that direction. Replication of these findings will be an important next step."

In discussing the impact of their findings, the researchers noted the vital role the test could have for patients, their physicians and companies involved in clinical trials. "A diagnostic test capable of distinguishing different stages of PD (Parkinson's disease) severity may make it possible to follow a patient's disease course, rate of progression and response to therapies," they wrote.

Under Dr. Nagele's direction, the research team has also found comparable results in a similar study involving subjects with mild cognitive impairment. That as-yet-unpublished study indicates that it is also possible to identify a small number of autoantibody biomarkers that can diagnose mild cognitive impairment and differentiate patients with mild cognitive impairment from those with mild-moderate Alzheimer's disease.