Stem-cell-based in vitro models offer promising potential to elucidate human brain cell functions and interactions, but limitations in reproducibility, maturation and cell-type diversity persist. Especially, prolonged incorporation of mature microglia and studies of neuroinflammation have proven challenging. Here, we developed a human induced pluripotent stem cell-based three-dimensional cortical brain tissue model (3BTM) containing neurons, astrocytes and microglia with high reproducibility, maturity and viability. 3BTMs show morphological, functional and proteomic maturation of all cell types, leading to high similarity to their in vivo counterparts. Incorporated microglia survive for over 6 months and display mature morphology, functions and gene expression. Importantly, when engineered to model Alzheimer’s disease pathology, 3BTMs recapitulate key disease hallmarks, including amyloid deposition, increased phospho-tau levels and neuroinflammation, with microglia shifting their transcriptional landscape to disease-relevant signatures. Treatment of Alzheimer’s disease 3BTMs with anti-Aβ immunotherapy cleared deposits and largely reversed disease signatures in glia. Together, our microglia-containing model provides a platform for studying physiological and pathological states of human brain tissue. Klimmt, Cardoso Gonçalves et al. developed a reproducible human three-dimensional brain tissue model with neurons, astrocytes and microglia, replicating in-vivo-like maturation and enabling the study of Alzheimer’s disease-relevant perturbations and drug responses.
Julien Klimmt, Carolina Cardoso Gonçalves, J. V. Montgomery et al.· Nature Neuroscience· 1 citation
Background Progressive supranuclear palsy (PSP) is a primary tauopathy defined by the accumulation of 4R tau isoforms in neurons, oligodendrocytes and astrocytes. Despite evidence of genetic susceptibility operating through glial cell types, it remains poorly understood how cell type-specific epigenetic-transcriptional programs evolve with progression of tau pathology. Methods We conducted single-nucleus chromatin accessibility (snATACseq) and RNA sequencing (snRNAseq) on postmortem frontal cortex samples from PSP patients (n = 8) and matched controls (n = 8), yielding over 144,000 nuclei passing quality control. Tau pathology burden, including neurofibrillary tangles, coiled bodies, and tufted astrocytes, was quantified on AT8-immunostained sections from the same individuals. We integrated differential gene expression analysis, transcription factor motif enrichment, weighted gene co-expression network analysis, and pseudotime modeling anchored to cell type-specific tau pathology burden to delineate molecular pseudo-progression trajectories. Results In eight cell types, 20 subclasses, and 70 subclusters, PSP brains displayed a selective depletion of certain excitatory deep-layer neurons and oligodendrocyte subclusters, with relative preservation of inhibitory neurons and vascular cells. Genetic risk enrichment was localized to astrocytes and oligodendrocytes, whereas excitatory neurons exhibited the greatest transcriptional dysregulation. Oligodendrocyte pseudo-progression indicated a transition from homeostatic myelination programs (MBP, MOBP) through glucocorticoid-responsive stress (FKBP5, ZBTB16), to compensatory myelination (PLP1, CNP) and proteostasis stress (UCHL1, CYRAB, CLU). Neuronal pseudo- progression revealed early dysregulation of synaptic (RORB2, NRG3, NPTX1), microtubule dynamics (KIF2C, RAB27B, TUBA/B), and survival (MEG3, FTX) pathways, alongside a transient increase in neuron-glia interactions (GRIP, CNTNAP4, ERBB4), converging late on ribosomal translation and vesicular trafficking modules across all neuronal subtypes. Cross-modal integration with independent cerebrospinal fluid proteomics identified a concordant subset of glial reactivity, axonal injury, and synaptic markers jointly dysregulated in inhibitory neurons, oligodendrocytes, and excitatory deep-layer neurons. Conclusion PSP pathogenesis reflects a combination of glial genetic susceptibility and staged, cell type-specific transcriptional dysfunction. Oligodendrocytes transition from myelination-competent states to FKBP5-mediated stress states, while neurons show variably timed loss of synaptic excitability and survival programs, preceded by neuron-glia interactions and followed by convergent ribosomal-proteostatic failure. These cytopathology-anchored trajectories outline a potential pathophysiological sequence and may inform candidate selection for stage-specific therapeutic interventions in PSP.
N. Briel, Viktoria C. Ruf, Paul L. C. Feyen et al.· bioRxiv· 0 citations
It is shown that early complement associated pruning of inhibitory synapses precedes overt α-synuclein aggregation and neuronal loss in prodromal synucleinopathy, indicating disease-context dependent relationships between αSyn pathology and neurodegeneration.
Svenja-Lotta Rumpf, Felix L. Struebing, Karsten Nalbach et al.· Nature Communications· 0 citations