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Related Experiment Video

Updated: Sep 29, 2025

In Vitro Modeling of Down Syndrome Neurogenesis Using Human-Induced Pluripotent Stem Cells

In Vitro Modeling of Down Syndrome Neurogenesis Using Human-Induced Pluripotent Stem Cells

Published on: March 7, 2025

Patterns of Mixed Pathologies in Down Syndrome.

Shojiro Ichimata^1,2, Koji Yoshida^1,2, Naomi P Visanji^1,3

¹Department of Laboratory Medicine and Pathobiology and Tanz Centre for Research in Neurodegenerative Disease, University of Toronto, Toronto, Canada.

Journal of Alzheimer'S Disease : JAD

|March 21, 2022

Summary

Down syndrome (DS) brains show Alzheimer's disease (AD) protein pathologies, but with unique features. Mixed proteinopathies, including Lewy-related pathology, TDP-43 encephalopathy, and tau astrogliopathy, present differently than in sporadic AD.

Keywords:

Age-related tau astrogliopathy Down syndrome alpha-synuclein amyloid-β cerebral amyloid angiopathy mixed pathology tau transactive response DNA binding protein 43 kDa

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Published on: December 18, 2016

Area of Science:

Neuroscience
Neuropathology
Genetics

Background:

Down syndrome (DS) frequently exhibits Alzheimer's disease (AD)-related neuropathological changes.
Limited data exists on the spectrum of mixed proteinopathies in DS patients.

Purpose of the Study:

To evaluate multiple disease-associated proteinopathies in postmortem brain samples from DS cases.
To characterize the distribution and staging of neurodegenerative proteins in DS.

Main Methods:

Analysis of postmortem brain samples from 11 DS cases (ages 38-66).
Immunohistochemical staining for phosphorylated tau, tau variants, amyloid-β, alpha synuclein, phosphorylated TDP-43, and p62.
Comprehensive anatomical mapping and staging of protein pathologies.

Main Results:

All cases showed tau and amyloid-β pathology consistent with AD, with subtle deviations.
Four cases displayed Lewy-related pathology (LRP), with two showing atypical distribution.
Two cases had limbic predominant age-related TDP-43 encephalopathy (LATE) and two had aging-related tau astrogliopathy (ARTAG).

Conclusions:

DS brains exhibit distinct features in mixed proteinopathies, including deviations in LRP staging.
LATE and ARTAG pathologies were observed in younger DS individuals compared to sporadic AD.
Down syndrome appears to involve distinct pathogenic pathways compared to sporadic AD.