Until now, the main means of diagnosing Parkinson’s has been restricted to the typical movement disorders such as tremors, slowing movements and stiffening of muscles. The disease begins up to 20 years before these symptoms appear, however. Until now there have been no blood indicators or imaging procedures suitable for giving a reliable diagnosis, and certainly not at such an early stage. This faces doctors with a dilemma. They would like to detect Parkinson’s disease during the early stages in order to be able to take measures that would prevent patients suffering from the symptoms. A number of working groups across the globe 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) have now made a joint breakthrough. They have developed a biochemical, blood-based test for diagnosing Parkinson’s disease. Using this new method, the researchers succeeded in differentiating patients from members of the control group with a very high degree of accuracy. The results have now been published in the journal “Brain”.
The method was developed by the Erlangen-based biochemist, Prof. Dr. Friederike Zunke, deputy head of the Department of Molecular Neurology at Universitätsklinikum Erlangen. Also closely involved in the study were Dr. Annika Kluge, lead author and physician in training at the Department of Neurology at 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 Universitätsklinikum Erlangen respectively, doctoral candidates 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 sensational results that can now be used to develop a blood test for diagnosing Parkinson’s disease. Work still has to be done on refining the method to make it suitable for large-scale use. It remains unclear whether the test will also be able to pick up on the disease in the early stages and whether it will work for diseases similar to Parkinson’s.
Direct proof of pathogenic protein in blood
The new method is based on three steps: After the first step of taking blood, the next step is to treat the blood sample to allow microvesicles released by nerve cells to 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 common blood sample. Basically, they can see into the patient’s brain by investigating these microvesicles. The third step then involves specifically looking for the protein that causes the disease in these isolated nerve cell microvesicles. The protein in question is a modified version of α-synuclein. An accumulation of this pathologically modified α-synuclein is directly involved in the destruction of the affected nerve cells. Using their method, the team of researchers has succeeded in tracking down the pathogenic protein in the blood using highly specific biochemical analyses of minute protein particles that trigger the disease. This now opens up opportunities for specifically looking for the misfolded protein and other early interventions.