Creating A Diagnostic Test Could Detect Parkinson’s Earlier
Giovanni Bellomo, PhD, of the University of Perugia received a Parkinson’s Foundation Postdoctoral Fellowship for Basic Scientists to improve the usefulness of a group of testing techniques called seed amplification assays (SAAs) in the early diagnosis of Parkinson’s disease (PD).
There is no single test to diagnose Parkinson’s disease. A movement disorder specialist often heavily relies on the presence of movement symptoms to make a diagnosis. However, these symptoms appear several years after changes start occurring in the brain. This means that by the time symptoms appear, the disease is already past its early phase. Early detection would allow earlier disease-modifying treatment, which could potentially benefit people with PD.
One of the earliest known changes in the brain that occurs in PD is the deposits of a protein called alpha-synuclein. These deposits can spread among brain cells and trigger changes in the brain that lead to Parkinson’s. Seed amplification assays have been successfully used to detect alpha-synuclein pathological changes in the cerebrospinal fluid (CSF) of people with Parkinson’s.
Tests like the seed amplification assays are used to detect a biomarker (a biological molecule that is a sign of disease). Having a biomarker for Parkinson’s could lead to earlier diagnosis and can improve outcomes for people living with PD.
Cerebrospinal fluid circulates around the brain and spinal cord. “Currently, alpha-synuclein SAA is the most promising technique for the biomarker-based diagnosis of PD, even at early stages,” said Dr. Bellomo. “However, several factors limit their use in clinical practice.”
First, collecting CSF is an invasive procedure. Second, there are still no standards for SAA. This results in disparities among different labs using the technique. Finally, the results of SAA testing do not provide enough detailed information to use in monitoring treatment.
“This research will improve the usefulness of SAAs in obtaining a specific and early diagnosis of PD. This is crucial for properly planning a treatment approach and including people with PD in clinical trials,” said Dr. Bellomo.
First, Dr. Bellomo will study whether olfactory mucosa can be used in SAA. Early PD-related alpha-synuclein alterations can be found in the olfactory mucosa. Collecting this sample is easily achieved by using a swab to scrape small amounts of olfactory mucosa from inside the nose.
The researcher will compare the results of SAAs in CSF and olfactory mucosa collected from people with and without PD. This non-intrusive test would represent a breakthrough in Parkinson's diagnosis, as no such test currently exists.
Second, Dr. Bellomo also aims to improve current CSF SAAs by making them capable of estimating the amount of disease-causing alpha-synuclein present in CSF samples. This is a key step toward testing treatments against pathological forms of alpha-synuclein. In addition, it will show how these estimates relate to PD symptoms.
Of his Parkinson’s Foundation grant award, he said, “This award means a lot to me. As the son of a person with Parkinson's, it will give me the opportunity to make a significant contribution in the field of Parkinson's disease diagnostics.”
Meet more Parkinson’s researchers! Explore our My PD Stories featuring PD researchers.