title: Preliminary Study of Plasma Exosomal Tau as a Potential Biomarker for Chronic Traumatic Encephalopathy.
abstract: BACKGROUND
  Chronic traumatic encephalopathy (CTE) is a tauopathy associated with prior exposure to repetitive head impacts, such as those incurred through American football and other collision sports. Diagnosis is made through neuropathological examination. Many of the clinical features of CTE are common in the general population, with and without a history of head impact exposure, making clinical diagnosis difficult. As is now common in the diagnosis of other neurodegenerative disorders, such as Alzheimer's disease, there is a need for methods to diagnose CTE during life through objective biomarkers.
  
  
  OBJECTIVE
  The aim of this study was to examine tau-positive exosomes in plasma as a potential CTE biomarker.
  
  
  METHODS
  Subjects were 78 former National Football League (NFL) players and 16 controls. Extracellular vesicles were isolated from plasma. Fluorescent nanoparticle tracking analysis was used to determine the number of vesicles staining positive for tau.
  
  
  RESULTS
  The NFL group had higher exosomal tau than the control group (p <  0.0001). Exosomal tau discriminated between the groups, with 82% sensitivity, 100% specificity, 100% positive predictive value, and 53% negative predictive value. Within the NFL group, higher exosomal tau was associated with worse performance on tests of memory (p = 0.0126) and psychomotor speed (p = 0.0093).
  
  
  CONCLUSIONS
  These preliminary findings suggest that exosomal tau in plasma may be an accurate, noninvasive CTE biomarker.
authors.affiliation: Boston University Alzheimer's Disease and CTE Center, Boston, MA, USA.|Department of Neurology, Boston University School of Medicine, Boston, MA, USA.|Department of Neurosurgery, Boston University School of Medicine, Boston, MA, USA.|Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA, USA.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Stern
authors.affiliation: Boston University Alzheimer's Disease and CTE Center, Boston, MA, USA.|Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA.
authors.forename: Yorghos
authors.initials: Y
authors.lastname: Tripodis
authors.affiliation: Boston University Alzheimer's Disease and CTE Center, Boston, MA, USA.
authors.forename: Christine M
authors.initials: CM
authors.lastname: Baugh
authors.affiliation: Boston University Alzheimer's Disease and CTE Center, Boston, MA, USA.
authors.forename: Nathan G
authors.initials: NG
authors.lastname: Fritts
authors.affiliation: Boston University Alzheimer's Disease and CTE Center, Boston, MA, USA.|Data Coordinating Center, Boston University School of Public Health, Boston, MA, USA.
authors.forename: Brett M
authors.initials: BM
authors.lastname: Martin
authors.affiliation: Boston University Alzheimer's Disease and CTE Center, Boston, MA, USA.|Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA.|Data Coordinating Center, Boston University School of Public Health, Boston, MA, USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Chaisson
authors.affiliation: Boston University Alzheimer's Disease and CTE Center, Boston, MA, USA.|Department of Neurology, Boston University School of Medicine, Boston, MA, USA.|Department of Neurosurgery, Boston University School of Medicine, Boston, MA, USA.|Department of Neurosurgery, Emerson Hospital, Concord, MA, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Cantu
authors.affiliation: Aethlon Medical, San Diego, CA, USA.
authors.forename: James A
authors.initials: JA
authors.lastname: Joyce
authors.affiliation: Exosome Sciences, San Diego, USA.
authors.forename: Sahil
authors.initials: S
authors.lastname: Shah
authors.affiliation: Department of Neurology, Boston University School of Medicine, Boston, MA, USA.|Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA.
authors.forename: Tsuneya
authors.initials: T
authors.lastname: Ikezu
authors.affiliation: Department of Pathology, University of Washington, Seattle, WA, USA.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Exosome Sciences, San Diego, USA.
authors.forename: Cicek
authors.initials: C
authors.lastname: Gercel-Taylor
authors.affiliation: Exosome Sciences, San Diego, USA.
authors.forename: Douglas D
authors.initials: DD
authors.lastname: Taylor
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D000070627:Chronic Traumatic Encephalopathy / Q000097:blood*; D000067128:Extracellular Vesicles / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010949:Plasma / Q000166:cytology*; D016875:tau Proteins / Q000378:metabolism*
chemical_list: D016875:tau Proteins
keywords: Biomarker; chronic traumatic encephalopathy; diagnosis; exosome; football; neurodegeneration; plasma; tau