Scientists Develop Blood Test With Promise for Early Diagnosis
Scientists in Germany have developed the first highly sensitive test to detect altered alpha-synuclein proteins in blood samples from patients with Parkinson’s disease.
The test accurately distinguishes people with Parkinson’s from those without the disease and has the potential to detect the disease early, before symptoms start, according to a new study.
“We developed a biochemical blood-based test for the diagnosis of Parkinson’s disease. With our procedure, we were able to distinguish the 30 Parkinson’s patients from the 50 control individuals with a very high degree of sensitivity,” Annika Kluge, MD, said in a press release. Kluge is from the Arbeitsgruppe Früherkennung Parkinson (working group on the early recognition of Parkinson’s) at the faculty of medicine at Kiel University.
The study, “Detection of neuron-derived pathological alpha-synuclein in blood,” was published in the journal Brain.
Clinicians currently diagnose Parkinson’s based on movement symptoms, neuroimaging scans, and invasive brain and spinal fluid tests that detect clumps of the alpha-synuclein protein. However, Parkinson’s has similar symptoms to other brain diseases such as dementia with Lewy bodies and is often misdiagnosed.
Moreover, it can take up to 20 years before symptoms of Parkinson’s disease begin to show, by which time it has far advanced with limited treatment options. Therefore, a noninvasive test that accurately detects Parkinson’s, preferably in its early stages, is needed.
“We would like to detect the disease in its early stages and develop measures to prevent patients from becoming stiff, shaky and slow,” Kluge said.
Researchers in Germany have now developed a blood test that could potentially achieve this. The test is based on detecting misfolded alpha-synuclein protein in brain vesicles — small structures that are pinched off brain cells — in the blood. The scientists initially detect these brain vesicles in blood samples and then identify the misfolded alpha-synuclein protein that cause the disease. These proteins are then extracted and researchers are able to reproduce their misfolded forms seen in people with Parkinson’s brains.
The team analyzed blood samples from 30 patients with Parkinson’s (mean age of 67 years) and 50 individuals who did not have the disease (mean age 79 years). The patients had an average disease duration of four years and a mean motor symptom score of 25 based on the Movement Disorder Society Unified Parkinson’s Disease Rating Scale Part 3.
The test was able to identify all patients with Parkinson’s and accurately distinguished blood samples of patients from individuals without the disease.
“The results are really sensational. They form the basis on which a blood test for diagnosing Parkinson’s disease can be developed,” said Daniela Berg, MD, director of the department of neurology at the University Medical Center Schleswig-Holstein, Campus Kiel.
“Whether early stages of the disease can also be detected and whether the test will work for diseases that are similar to Parkinson’s are questions yet to be answered,” Berg added.
More studies are needed to fine-tune the blood test and make it suitable for widespread use.
“Our study supports the approach that instead of focusing on quantitative alpha synuclein level in body fluids or tissues, the detection of pathological [diseased] neuronal alpha synuclein conformers should be targeted,” the researchers concluded.
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