Abstract
INTRODUCTION
Tau aggregation into paired helical filaments and neurofibrillary tangles is characteristic of Alzheimer’s disease (AD) and related disorders. However, biochemical assays for the quantification of soluble, earlier-stage tau aggregates are lacking. We describe an immunoassay that is selective for tau oligomers and related soluble aggregates over monomers.
METHODS
A homogeneous (single-antibody) immunoassay was developed using a novel anti-tau monoclonal antibody and validated with recombinant and brain tissue–derived tau.
RESULTS
The assay signals were concentration dependent for recombinant tau aggregates in solution but not monomers, and recognized peptides within, but not outside, the aggregation-prone microtubule binding region. The signals in inferior and middle frontal cortical tissue homogenates increased with neuropathologically determined Braak staging, and were higher in insoluble than soluble homogenized brain fractions. Autopsy-verified AD gave stronger signals than other neurodegenerative diseases.
DISCUSSION
The quantitative oligomer/soluble aggregate-specific assay can identify soluble tau aggregates, including oligomers, from monomers in human and in vitro biospecimens.
Highlights
The aggregation of tau to form fibrils and neurofibrillary tangles is a key feature of Alzheimer’s disease.
However, biochemical assays for the quantification of oligomers/soluble aggregated forms of tau are lacking.
We developed a new assay that preferentially binds to soluble tau aggregates, including oligomers and fibrils, versus monomers.
The assay signal increased corresponding to the total protein content, Braak staging, and insolubility of the sequentially homogenized brain tissue fractions in an autopsy-verified cohort.
The assay recognized tau peptides containing the microtubule binding region but not those covering the N- or C-terminal regions only.
If you do not see content above, kindly GO TO SOURCE.
Not all publishers encode content in a way that enables republishing at Neuro.vip.
This post is Copyright: Tohidul Islam,
Hlin Kvartsberg,
Anuradha Sehrawat,
Przemysław R. Kac,
Bruno Becker,
Maria Olsson,
Eric E. Abrahamson,
Henrik Zetterberg,
Milos D. Ikonomovic,
Kaj Blennow,
Thomas K. Karikari | March 23, 2024