Lewy body extracts from Parkinson disease brains trigger α‐synuclein pathology and neurodegeneration in mice and monkeys

α-Synuclein species contained in PD-derived LB are pathogenic and have the capacity to initiate a PD-like pathological process, including intracellular and presynaptic accumulations of pathological α-synuclein in different brain areas and slowly progressive axon-initiated dopaminergic nigrostriatal neurodegeneration.