title: Apolipoproteins and their subspecies in human cerebrospinal fluid and plasma.
abstract: BACKGROUND
  Subspecies of apolipoproteins can be defined by fractionating apolipoproteins based on the presence and absence of coexisting apolipoproteins.
  
  
  METHODS
  We determined age- and sex-adjusted correlations of enzyme-linked immunosorbent assay-measured plasma and cerebrospinal fluid (CSF) apolipoproteins (apoA-I, apoC-III, apoE, and apoJ) or apolipoprotein subspecies (apoA-I with and without apoC-III, ApoE, or apoJ; apoE with and without apoC-III or apoJ) in 22 dementia-free participants.
  
  
  RESULTS
  CSF apoE did not correlate with plasma apolipoproteins or their subspecies. CSF apoJ correlated most strongly with plasma apoA-I without apoJ (r= 0.7). CSF apoA-I correlated similarly strong with plasma total apoA-I and all apoA-I subspecies (r≥ 0.4) except for apoA-I with apoE (r= 0.3) or apoA-I with apoJ (r= 0.3). CSF apoC-III was most strongly correlated with plasma apoA-I with apoC-III (r= 0.7).
  
  
  CONCLUSIONS
  CSF levels of some apolipoproteins implicated in the pathophysiology of dementia might be better approximated by specific plasma apolipoprotein subspecies than total plasma concentrations.
authors.affiliation: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: Manja
authors.initials: M
authors.lastname: Koch
authors.affiliation: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: Jeremy D
authors.initials: JD
authors.lastname: Furtado
authors.affiliation: Neuroimmunology Unit, Christian-Albrechts-University Kiel, Kiel, Germany; Department of Neurology, Institute of Clinical Chemistry, University Hospital Schleswig-Holstein, Kiel, Germany.
authors.forename: Kim
authors.initials: K
authors.lastname: Falk
authors.affiliation: Neuroimmunology Unit, Christian-Albrechts-University Kiel, Kiel, Germany; Department of Neurology, Institute of Clinical Chemistry, University Hospital Schleswig-Holstein, Kiel, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Leypoldt
authors.affiliation: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA.
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Mukamal
authors.affiliation: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Department of Medicine, Channing Division of Network Medicine, Harvard Medical School, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Majken K
authors.initials: MK
authors.lastname: Jensen
keywords: Apolipoprotein subspecies; Apolipoproteins; Brain; Cerebrospinal fluid; Lipoproteins