title: Pathological interface between oligomeric alpha-synuclein and tau in synucleinopathies.
abstract: BACKGROUND
  Aberrant accumulation of α-synuclein constitutes inclusion bodies that are considered a characteristic feature of a group of neurological disorders described as synucleinopathies. Often, multiple disease-causing proteins overlap within a given disease pathology. An emerging body of research focuses on the oligomeric populations of various pathogenic proteins, considering them as the culprits causing neuronal damage and degeneration. To this end, the use of conformation-specific antibodies has proven to be an effective tool. Previous work from our laboratory and others has shown that oligomeric entities of α-synuclein and tau accumulate in their respective diseases, but their interrelationship at this higher order has yet to be shown in synucleinopathies.
  
  
  METHODS
  Here, we used two novel conformation-specific antibodies, F8H7 and Syn33, which recognize α-synuclein oligomers and were developed in our laboratory. We investigated brain tissue from five of each Parkinson's disease and dementia with Lewy bodies patients by performing biophysical and biochemical assays using these antibodies, in addition to the previously characterized anti-tau oligomer antibody T22.
  
  
  RESULTS
  We demonstrate that in addition to the deposition of oligomeric α-synuclein, tau oligomers accumulate in these diseased brains compared with control brains. Moreover, we observed that oligomers of tau and α-synuclein exist in the same aggregates, forming hybrid oligomers in these patients' brains.
  
  
  CONCLUSIONS
  In addition to the deposition of tau oligomers, our results also provide compelling evidence of co-occurrence of α-synuclein and tau into their most toxic forms, i.e., oligomers suggesting that these species interact and influence each other's aggregation via an interface in synucleinopathies.
authors: Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas.
authors: Urmi
authors: U
authors: Sengupta
authors: Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas.
authors: Marcos J
authors: MJ
authors: Guerrero-Muñoz
authors: Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas.
authors: Diana L
authors: DL
authors: Castillo-Carranza
authors: Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas.
authors: Cristian A
authors: CA
authors: Lasagna-Reeves
authors: Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas.
authors: Julia E
authors: JE
authors: Gerson
authors: Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, Texas.
authors: Adriana A
authors: AA
authors: Paulucci-Holthauzen
authors: Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas.
authors: Shashirekha
authors: S
authors: Krishnamurthy
authors: Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas.
authors: Malika
authors: M
authors: Farhed
authors: Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas; Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, Texas.
authors: George R
authors: GR
authors: Jackson
authors: Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas; Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, Texas. Electronic address: rakayed@utmb.edu.
authors: Rakez
authors: R
authors: Kayed
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000906:Antibodies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005625:Frontal Lobe / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D020961:Lewy Body Disease / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000378:metabolism* / Q000473:pathology; D010300:Parkinson Disease / Q000378:metabolism* / Q000473:pathology; D051844:alpha-Synuclein / Q000276:immunology / Q000378:metabolism*; D016875:tau Proteins / Q000276:immunology / Q000378:metabolism*
chemical_list: D000906:Antibodies; C054369:MAPT protein, human; D051844:alpha-Synuclein; D016875:tau Proteins
keywords: Co-aggregation; Hybrid oligomers; Interaction; Synucleinopathy; Tau oligomers; α-Synuclein oligomers