Ammonium hydroxide treatment of Aβ produces an aggregate free solution suitable for biophysical and cell culture characterization

PeerJ. 2013;1:e73 DOI 10.7717/peerj.73

 

Journal Homepage

Journal Title: PeerJ

ISSN: 2167-8359 (Online)

Publisher: PeerJ Inc.

LCC Subject Category: Medicine

Country of publisher: United States

Language of fulltext: English

Full-text formats available: PDF, HTML, XML

 

AUTHORS

Timothy M. Ryan (The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia)
Joanne Caine (Materials Science and Engineering, Preventative Health Flagship, Commonwealth Scientific and Industrial Research Organization, Parkville, Victoria, Australia)
Haydyn D.T. Mertens (SAXS/WAXS Beamline, Australian Synchrotron, Clayton, Victoria, Australia)
Nigel Kirby (SAXS/WAXS Beamline, Australian Synchrotron, Clayton, Victoria, Australia)
Julie Nigro (Materials Science and Engineering, Preventative Health Flagship, Commonwealth Scientific and Industrial Research Organization, Parkville, Victoria, Australia)
Kerry Breheney (Materials Science and Engineering, Preventative Health Flagship, Commonwealth Scientific and Industrial Research Organization, Parkville, Victoria, Australia)
Lynne J. Waddington (Materials Science and Engineering, Preventative Health Flagship, Commonwealth Scientific and Industrial Research Organization, Parkville, Victoria, Australia)
Victor A. Streltsov (Materials Science and Engineering, Preventative Health Flagship, Commonwealth Scientific and Industrial Research Organization, Parkville, Victoria, Australia)
Cyril Curtain (The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia)
Colin L. Masters (The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia)
Blaine R. Roberts (The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia)

EDITORIAL INFORMATION

Blind peer review

Editorial Board

Instructions for authors

Time From Submission to Publication: 10 weeks

 

Abstract | Full Text | Full Text

Alzheimer’s disease is the leading cause of dementia in the elderly. Pathologically it is characterized by the presence of amyloid plaques and neuronal loss within the brain tissue of affected individuals. It is now widely hypothesised that fibrillar structures represent an inert structure. Biophysical and toxicity assays attempting to characterize the formation of both the fibrillar and the intermediate oligomeric structures of Aβ typically involves preparing samples which are largely monomeric; the most common method by which this is achieved is to use the fluorinated organic solvent 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP). Recent evidence has suggested that this method is not 100% effective in producing an aggregate free solution. We show, using dynamic light scattering, size exclusion chromatography and small angle X-ray scattering that this is indeed the case, with HFIP pretreated Aβ peptide solutions displaying an increased proportion of oligomeric and aggregated material and an increased propensity to aggregate. Furthermore we show that an alternative technique, involving treatment with strong alkali results in a much more homogenous solution that is largely monomeric. These techniques for solubilising and controlling the oligomeric state of Aβ are valuable starting points for future biophysical and toxicity assays.