| α-Synuclein (α-syn) is a small protein with an inherent tendency to aggregate and is implicated in several neurodegenerative diseases, including Parkinson’s disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA), collectively referred to as synucleinopathies. Evidence from genetic, pathological, biochemical, and animal model studies strongly supports the role of α-syn aggregation in developing PD and related synucleinopathies. Therefore, developing reliable tools to detect aggregated forms of ?-syn is critical.
Here, we report the creation and characterization of six novel conformation-specific monoclonal antibodies that selectively recognize α-syn aggregates, without binding to its soluble, monomeric form. These antibodies did not recognize monomers or fibrils generated from other amyloidogenic proteins, such as β-syn, γ-syn, β-amyloid, tau, islet amyloid polypeptide, or ABri. Moreover, they did not bind to overlapping linear peptides covering the entire α-syn sequence, confirming their specificity for aggregated α-syn.
In immunohistochemistry, these conformation-specific antibodies revealed previously unappreciated small micro-aggregates and thin neurites in PD and DLB cases, which were not detected by pan antibodies that recognize linear epitopes. Additionally, using one of the antibodies in a sandwich-based ELISA, we detected elevated levels of ?-syn oligomers in brain lysates from DLB cases compared to Alzheimer’s disease and control samples. These conformation-specific antibodies represent valuable tools for research, biomarker development, diagnosis, and potentially immunotherapy for PD and related diseases. |
