Polarimetric imaging of amyloid

Kaminksy, Werner; Jin, Lee Way; Powell, Steven; Maezawa, Izumi; Claborn, Kacey; Branham, Charles W.; Kahr, Bart

doi:10.1016/j.micron.2005.10.014

Cited by 25 publications

(21 citation statements)

References 95 publications

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“…The mechanism that explains them differs from other processes postulated to give the colours in Congo red‐stained amyloid. Interference colours, such as those seen in soap bubbles, have been suggested, but require much larger retardances, or differences in the phase of waves, than those ever measured in sections of Congo red‐stained amyloid . Detection of interference colours between crossed polarizer and analyser requires retardances of whole wavelengths, but reported retardances in Congo red‐stained amyloid have invariably been under half of any wavelength .…”

Section: First Report Of Colours In Congo Red‐stained Amyloidmentioning

confidence: 99%

Origins of a pervasive, erroneous idea: The “green birefringence” of Congo red‐stained amyloid

Howie

2019

Int J Experimental Path

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Summary Congo red was discovered to stain amyloid by accident in 1922, and Congo red‐stained amyloid was shown to be birefringent on polarization microscopy in 1927. Colours, namely green and yellow, were reported under these conditions in 1945, although these are only two of various anomalous colours that may be seen, depending on the optical set‐up. In 1953 there began a dogmatic insistence that in Congo red‐stained amyloid between crossed polarizer and analyser green alone should be seen, and the finding of any other colour was a mistake. The idea that green, and only green, is essential for the diagnosis of amyloid has persisted almost universally, and virtually all mentions of Congo red‐stained amyloid say that it just shows “green birefringence” or “apple‐green birefringence.” This idea is wrong and is contrary to everyday experience, because green is seldom seen on its own under these conditions of microscopy, and often, there is no green at all. How observers maintain this unscientific position is explained by a study of its historical origins. Most of the early literature was in German or French and was usually quoted in English at second hand, which meant that misquotations, misattributions and misunderstandings were common. Few workers reported their findings accurately, hardly any attempted to explain them, and until 2008, none gave a completely satisfactory account of the physical optics. The history of Congo red‐stained amyloid is an instructive example of how an erroneous belief can become widely established even when it is contradicted by simple experience.

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Section: First Report Of Colours In Congo Red‐stained Amyloidmentioning

confidence: 99%

Origins of a pervasive, erroneous idea: The “green birefringence” of Congo red‐stained amyloid

Howie

2019

Int J Experimental Path

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“…Previously, polarization microscopy has been used extensively to image ordered supramolecular structures in live cells [12][13][14][15][16], as well as to study the formation of intracellular aggregates [17]. This led us to consider combining quantitative polarization microscopy together with fluorescence and transmittance measurements to facilitate multiparameter cytometric analysis of molecular aggregates formation at a single cell level.…”

Section: Introductionmentioning

confidence: 99%

Detecting ordered small molecule drug aggregates in live macrophages: a multi-parameter microscope image data acquisition and analysis strategy

Rzeczycki

Yoon

Keswani

et al. 2017

Biomed. Opt. Express

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Abstract:Following prolonged administration, certain orally bioavailable but poorly soluble small molecule drugs are prone to precipitate out and form crystal-like drug inclusions (CLDIs) within the cells of living organisms. In this research, we present a quantitative multiparameter imaging platform for measuring the fluorescence and polarization diattenuation signals of cells harboring intracellular CLDIs. To validate the imaging system, the FDAapproved drug clofazimine (CFZ) was used as a model compound. Our results demonstrated that a quantitative multi-parameter microscopy image analysis platform can be used to study drug sequestering macrophages, and to detect the formation of ordered molecular aggregates formed by poorly soluble small molecule drugs in animals.

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“…We next assessed binding of F1 to AL and AA amyloid-laden patient renal tissue sections. Amyloid deposition in the tissues was demonstrated by apple green Congo red birefringence, which is known to detect some, but not all, amyloid (42) (Fig. 3B).…”

Section: Table 1 Monoclonal Human Igg and Hc Binding To Amyloid Fibrimentioning

confidence: 99%

Inherent Anti-amyloidogenic Activity of Human Immunoglobulin γ Heavy Chains

Adekar

Klyubin

Macy

et al. 2010

Journal of Biological Chemistry

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We have previously shown that a subpopulation of naturally occurring human IgGs were cross-reactive against conformational epitopes on pathologic aggregates of A␤, a peptide that forms amyloid fibrils in the brains of patients with Alzheimer disease, inhibited amyloid fibril growth, and dissociated amyloid in vivo. Here, we describe similar anti-amyloidogenic activity that is a general property of free human Ig ␥ heavy chains. A ␥ 1 heavy chain, F1, had nanomolar binding to an amyloid fibril-related conformational epitope on synthetic oligomers and fibrils as well as on amyloidladen tissue sections. F1 did not bind to native A␤ monomers, further indicating the conformational nature of its binding site. The inherent anti-amyloidogenic activity of Ig ␥ heavy chains was demonstrated by nanomolar amyloid fibril and oligomer binding by polyclonal and monoclonal human heavy chains that were isolated from inert or weakly reactive antibodies. Most importantly, the F1 heavy chain prevented in vitro fibril growth and reduced in vivo soluble A␤ oligomer-induced impairment of rodent hippocampal long term potentiation, a cellular mechanism of learning and memory. These findings demonstrate that free human Ig ␥ heavy chains comprise a novel class of molecules for developing potential therapeutics for Alzheimer disease and other amyloid disorders. Moreover, establishing the molecular basis for heavy chain-amyloidogenic conformer interactions should advance understanding on the types of interactions that these pathologic assemblies have with biological molecules. Alzheimer disease (AD)3 is approaching global epidemic proportions and is the most common of over 25 incurable protein misfolding diseases that are termed the amyloidoses (1, 2). A hallmark of the disease is deposition of amyloid fibril-containing neuritic plaques that are formed by abnormal processing of ␤-amyloid protein (A␤), a proteolyzed transmembrane 39 -43 fragment of amyloid precursor protein (3). Diverse experimental studies support a central pathogenic role for aggregated A␤, which in the brain initiates a cascade of events that ultimately lead to neuronal dysfunction and death (4 -6). The most neurotoxic A␤ species are low molecular weight oligomers (5), which include noncovalently linked species (7-9) and dityrosine cross-linked ␤-amyloid protein species (CAPS) (10).Active vaccination with A␤ or passive administration of anti-A␤ antibodies has shown promise in transgenic AD animal models and in some AD patients by inducing neuritic plaque clearance, neutralizing neurotoxic soluble A␤ oligomers, and/or improving cognitive functioning (6,8,(11)(12)(13). Immunotherapy has generally targeted linear sequence epitopes on A␤ (13). However, antibodies that do not distinguish between pathologic A␤ conformers and the monomeric peptide may have adverse effects because the native peptide has been implicated in normal lipid and cholesterol homeostasis (14). Of potentially greater use are antibodies that cross-react with conformational epitopes on pathogenic aggregated A...

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Polarimetric imaging of amyloid

Cited by 25 publications

References 95 publications

Origins of a pervasive, erroneous idea: The “green birefringence” of Congo red‐stained amyloid

Origins of a pervasive, erroneous idea: The “green birefringence” of Congo red‐stained amyloid

Detecting ordered small molecule drug aggregates in live macrophages: a multi-parameter microscope image data acquisition and analysis strategy

Inherent Anti-amyloidogenic Activity of Human Immunoglobulin γ Heavy Chains

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