Blood test for Parkinson’s at your fingertips for the first time

Until now, the main means of diagnosing Parkinson’s has been limited to the typical movement disorders such as tremors, slow movements and stiffening of muscles. However, the disease starts up to 20 years before these symptoms appear. Until now, there are no blood indicators or imaging procedures suitable for making a reliable diagnosis, especially at such an early stage. This presents doctors with a dilemma. They want to detect Parkinson’s disease at an early stage in order to be able to take measures to prevent patients from developing the symptoms. A number of working groups around the world are looking for reliable clinical biomarkers for the chronic degenerative brain disease. A team of researchers from Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Universitätsklinikum Schleswig-Holstein and Christian-Albrechts-Universität zu Kiel (CAU) has now achieved a joint breakthrough. They have developed a biochemical, blood-based test to diagnose Parkinson’s disease. With this new method, the researchers managed to distinguish patients from members of the control group with a very high degree of accuracy. The results are now published in the magazine “Brain”†

The method was developed by the biochemist from Erlangen, Prof. dr. Friederike Zunke, Deputy Head of the Department of Molecular Neurology at the Universitätsklinikum Erlangen. Also deeply involved in the study were Dr. Annika Kluge, lead author and physician trainee at the Department of Neurology at the Universitätsklinikum Schleswig-Holstein, PD Dr. Philipp Arnold and PD Dr. Wei Xiang, research associates at the Institute of Anatomy at FAU and the Department of Molecular Neurology at the Universitätsklinikum Erlangen, PhD students Alice Drobny and Josina Bunk, Prof. dr. Daniela Berg, Director of the Department of Neurology at Universitätsklinikum Schleswig-Holstein, and Prof. dr. Ralph Lucius, Director of the Institute of Anatomy at CAU. The interdisciplinary team is delighted with the startling results that can now be used to develop a blood test for the diagnosis of Parkinson’s disease. Work still needs to be done on refining the method to make it suitable for large-scale use. It remains unclear whether the test can also pick up the disease at an early stage and whether it works in diseases similar to Parkinson’s.

Direct evidence of pathogenic protein in blood

The new method is based on three steps: After the first step of drawing blood, the next step is to treat the blood sample so that microvesicles released by nerve cells can be isolated. Microvesicles are small particles released by cells that contain proteins from the original cell. This method allows researchers to extract microvesicles from the nervous system using a regular blood sample. Basically, they can look inside the patient’s brain by examining these microvesicles. The third step is then a targeted search for the protein that causes the disease in these isolated nerve cell microvesicles. The protein in question is a modified version of -synuclein. An accumulation of this pathologically modified -synuclein is directly involved in the destruction of the affected nerve cells. With their method, the team of researchers has succeeded in detecting the pathogenic protein in the blood using highly specific biochemical analyzes of tiny protein particles that cause the disease. This now offers opportunities to specifically look for the misfolded protein and other early interventions.