High Resolution Discovery Proteomics Reveals Candidate Disease Progression Markers of Alzheimer's Disease in Human Cerebrospinal Fluid

PLoS One. 2015 Aug 13;10(8):e0135365. doi: 10.1371/journal.pone.0135365. eCollection 2015.

Abstract

Disease modifying treatments for Alzheimer's disease (AD) constitute a major goal in medicine. Current trends suggest that biomarkers reflective of AD neuropathology and modifiable by treatment would provide supportive evidence for disease modification. Nevertheless, a lack of quantitative tools to assess disease modifying treatment effects remains a major hurdle. Cerebrospinal fluid (CSF) biochemical markers such as total tau, p-tau and Ab42 are well established markers of AD; however, global quantitative biochemical changes in CSF in AD disease progression remain largely uncharacterized. Here we applied a high resolution open discovery platform, dMS, to profile a cross-sectional cohort of lumbar CSF from post-mortem diagnosed AD patients versus those from non-AD/non-demented (control) patients. Multiple markers were identified to be statistically significant in the cohort tested. We selected two markers SME-1 (p<0.0001) and SME-2 (p = 0.0004) for evaluation in a second independent longitudinal cohort of human CSF from post-mortem diagnosed AD patients and age-matched and case-matched control patients. In cohort-2, SME-1, identified as neuronal secretory protein VGF, and SME-2, identified as neuronal pentraxin receptor-1 (NPTXR), in AD were 21% (p = 0.039) and 17% (p = 0.026) lower, at baseline, respectively, than in controls. Linear mixed model analysis in the longitudinal cohort estimate a decrease in the levels of VGF and NPTXR at the rate of 10.9% and 6.9% per year in the AD patients, whereas both markers increased in controls. Because these markers are detected by mass spectrometry without the need for antibody reagents, targeted MS based assays provide a clear translation path for evaluating selected AD disease-progression markers with high analytical precision in the clinic.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / cerebrospinal fluid*
  • Biomarkers / cerebrospinal fluid
  • C-Reactive Protein / cerebrospinal fluid*
  • Female
  • Humans
  • Male
  • Mass Spectrometry*
  • Middle Aged
  • Nerve Growth Factors / cerebrospinal fluid*
  • Nerve Tissue Proteins / cerebrospinal fluid*
  • Proteomics*

Substances

  • Biomarkers
  • Nerve Growth Factors
  • Nerve Tissue Proteins
  • VGF protein, human
  • neuronal pentraxin
  • C-Reactive Protein

Grants and funding

This discovery proteomics and analysis work was supported by Merck & Co. The manuscript was reviewed and approved for publication by Merck. The funders had no other role in the study design, data collection and analysis or preparation of the manuscript. The specific roles of the authors are articulated in the "author contribution" section.