Dataset Information

Noninvasive Antemortem Detection of Retinal Prions by a Fluorescent Tracer.

ABSTRACT:

Background

Neurodegenerative diseases are widespread yet challenging to diagnose and stage antemortem. As an extension of the central nervous system, the eye harbors retina ganglion cells vulnerable to degeneration, and visual symptoms are often an early manifestation of neurodegenerative disease.

Objective

Here we test whether prion protein aggregates could be detected in the eyes of live mice using an amyloid-binding fluorescent probe and high-resolution retinal microscopy.

Methods

We performed retinal imaging on an experimental mouse model of prion-associated cerebral amyloid angiopathy in a longitudinal study. An amyloid-binding fluorophore was intravenously administered, and retinal imaging was performed at timepoints corresponding to early, mid-, and terminal prion disease. Retinal amyloid deposits were quantified and compared to the amyloid load in the brain.

Results

We report that by early prion disease (50% timepoint), discrete fluorescent foci appeared adjacent to the optic disc. By later timepoints, the fluorescent foci surrounded the optic disc and tracked along retinal vasculature.

Conclusion

The progression of perivascular amyloid can be directly monitored in the eye by live imaging, illustrating the utility of this technology for diagnosing and monitoring the progression of cerebral amyloid angiopathy.

SUBMITTER: Aguilar-Calvo P

PROVIDER: S-EPMC10080909 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Publications

Noninvasive Antemortem Detection of Retinal Prions by a Fluorescent Tracer.

Aguilar-Calvo Patricia P Sevillano Alejandro M AM Rasool Suhail S Cao Kevin J KJ Randolph Lyndsay M LM Rissman Robert A RA Sarraf Stella T ST Yang Jerry J Sigurdson Christina J CJ

Journal of Alzheimer's disease : JAD 20220101 3

<h4>Background</h4>Neurodegenerative diseases are widespread yet challenging to diagnose and stage antemortem. As an extension of the central nervous system, the eye harbors retina ganglion cells vulnerable to degeneration, and visual symptoms are often an early manifestation of neurodegenerative disease.<h4>Objective</h4>Here we test whether prion protein aggregates could be detected in the eyes of live mice using an amyloid-binding fluorescent probe and high-resolution retinal microscopy.<h4>M ...[more]

PMID: 35754278

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Dataset Information

Noninvasive Antemortem Detection of Retinal Prions by a Fluorescent Tracer.

Background

Objective

Methods

Results

Conclusion

Publications

Noninvasive Antemortem Detection of Retinal Prions by a Fluorescent Tracer.

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