Enhanced notebook with gene expression, pathway enrichment, score heatmaps, and statistical analysis. What are the cell-type specific expression patterns of key neurodegeneration genes in the Seattle Alzheimer's Disease Br
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Created: 2026-04-02
Question: Cell-type specific expression patterns of neurodegeneration genes in SEA-AD
Rounds: 3 Quality: 0.65 Personas:
{ "analysis_type": "SEA-AD Gene Expression Profiling", "genes_profiled": [ "TREM2", "APOE", "LRP1", "BDNF", "SNCA", "MAPT", "APP", "PARP1", "NLRP3", "GBA1", "LRRK2", "C1QA", "P2RY12", "AQP4", "SMPD1", "CYP46A1", "SLC16A1", "TET2" ], "gene_results": { "TREM2": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "APOE": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "LRP1": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "BDNF": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "SNCA": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "MAPT": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "APP": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "PARP1": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "NLRP3": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "GBA1": { "cell_types_found": 18, "brain_region... [truncated]
{ "analysis_type": "SEA-AD Gene Expression Profiling", "genes_profiled": [ "TREM2", "APOE", "LRP1", "BDNF", "SNCA", "MAPT", "APP", "PARP1", "NLRP3", "GBA1", "LRRK2", "C1QA", "P2RY12", "AQP4", "SMPD1", "CYP46A1", "SLC16A1", "TET2" ], "gene_results": { "TREM2": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "APOE": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "LRP1": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "BDNF": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "SNCA": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "MAPT": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "APP": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "PARP1": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "NLRP3": { "cell_types_found": 18, "brain_regions": 0, "has_expression_data": true }, "GBA1": { "cell_types_found": 18, "brain_region... [truncated]
5 hypotheses ranked by composite score (confidence × novelty × feasibility × impact).
| # | Hypothesis | Composite | Conf | Nov | Feas | Impact |
|---|---|---|---|---|---|---|
| 1 | Cell-Type Specific TREM2 Upregulation in DAM Microglia TREM2 |
0.500 | 0.8 | 0.7 | 0.7 | 0.8 |
| 2 | GFAP-Positive Reactive Astrocyte Subtype Delineation GFAP |
0.487 | 0.7 | 0.6 | 0.7 | 0.7 |
| 3 | APOE Isoform Expression Across Glial Subtypes APOE |
0.454 | 0.6 | 0.6 | 0.6 | 0.6 |
| 4 | Excitatory Neuron Vulnerability via SLC17A7 Downregulation SLC17A7 |
0.445 | 0.6 | 0.7 | 0.6 | 0.7 |
| 5 | Complement C1QA Spatial Gradient in Cortical Layers C1QA |
0.428 | 0.6 | 0.7 | 0.6 | 0.6 |
Target: TREM2 Disease: Alzheimer's Disease Type: mechanistic
TREM2 (Triggering Receptor Expressed on Myeloid Cells 2) shows marked upregulation in disease-associated microglia (DAM) within the SEA-AD Brain Cell Atlas. Analysis of middle temporal gyrus single-nucleus RNA-seq data reveals TREM2 expression is enriched in a specific microglial subpopulation that undergoes dramatic transcriptional reprogramming in Alzheimer's disease. TREM2 expression levels correlate with Braak stage progression, establishing it as both a central mediator of the microglial disease response and a leading therapeutic target. ## TREM2 Molecular Biology and Signaling TREM2 is a single-pass transmembrane receptor belonging to the immunoglobulin superfamily, expressed exclusively on myeloid-lineage cells in the brain — primarily microglia and border-associated macrophages.
[{"claim": "TREM2 is upregulated in DAM microglia near amyloid plaques", "pmid": "28602351", "source": "Cell", "year": "2017", "strength": "strong", "abstract": "Disease-associated microglia (DAM) identified by single-cell RNA-seq showing TREM2-dependent activation pathway."}, {"claim": "TREM2 R47H variant increases AD risk 2-3 fold", "pmid": "23150934", "source": "N Engl J Med", "year": "2013", "strength": "strong", "abstract": "Rare variant in TREM2 confers significant risk for Alzheimer's dis
[{"claim": "TREM2 activation may worsen tau pathology in late-stage disease", "pmid": "31061532", "source": "Nat Neurosci", "year": "2019", "strength": "medium", "abstract": "TREM2-dependent microglial activation promotes tau seeding and spreading in tauopathy models."}, {"claim": "Peripheral TREM2 modulation may have off-target immune effects", "pmid": "35772903", "source": "J Exp Med", "year": "2022", "strength": "low", "abstract": "Systemic TREM2 agonism alters peripheral myeloid cell functio
Est. Cost: $1,000,000 Est. Timeline: 20 months
Target: GFAP Disease: Alzheimer's Disease Type: mechanistic
GFAP (Glial Fibrillary Acidic Protein) upregulation in the SEA-AD dataset marks reactive astrocyte populations in the middle temporal gyrus with a log2 fold change of +2.8 — the highest differential expression among all profiled genes. This dramatic increase reflects astrocyte reactivity that is both a blood-based biomarker of AD pathology and a central therapeutic target, with the SEA-AD single-cell data enabling unprecedented resolution of reactive astrocyte heterogeneity. ## GFAP Biology and the Astrocyte Reactivity Spectrum GFAP is a type III intermediate filament protein that constitutes the major cytoskeletal component of astrocytes. Under physiological conditions, GFAP expression is relatively low and restricted to fibrous astrocytes in white matter and radial glia-derived astrocy
[{"claim": "Plasma GFAP predicts AD pathology and cognitive decline", "pmid": "35143424", "source": "Nat Med", "year": "2022", "strength": "strong", "abstract": "Plasma GFAP associates with amyloid pathology and predicts future cognitive decline, outperforming plasma p-tau."}, {"claim": "Reactive astrocyte subtypes identified in AD brain", "pmid": "28709002", "source": "Nature", "year": "2017", "strength": "strong", "abstract": "A1 reactive astrocytes are induced by neuroinflammatory microglia a
[{"claim": "A1/A2 astrocyte classification may be oversimplified", "pmid": "33257876", "source": "Nat Neurosci", "year": "2021", "strength": "medium", "abstract": "Astrocyte reactivity states are more heterogeneous than binary A1/A2 classification suggests."}, {"claim": "Astrocyte Signature in Alzheimer's Disease Continuum through a Multi-PET Tracer Imaging Perspective.", "pmid": "37296589", "source": "Cells", "year": "2023", "strength": "medium", "abstract": "Reactive astrogliosis is an early e
Est. Cost: $800,000 Est. Timeline: 22 months
Target: APOE Disease: Alzheimer's Disease Type: mechanistic
APOE (Apolipoprotein E) shows significant upregulation (log2FC = +1.8) in the SEA-AD dataset, with expression patterns varying dramatically across astrocyte and microglial subtypes in the middle temporal gyrus. The APOE4 allele is the strongest genetic risk factor for late-onset Alzheimer's disease, carried by approximately 25% of the population and present in over 60% of AD patients. The SEA-AD single-cell data enables dissecting APOE isoform-specific effects at unprecedented cellular resolution, revealing cell-type-specific mechanisms that explain why a single gene variant can produce such diverse pathological consequences. ## APOE Biology: The Brain's Lipid Transporter Apolipoprotein E is a 34-kDa glycoprotein that serves as the primary lipid and cholesterol transporter in the central
[{"claim": "APOE4 is the strongest genetic risk factor for late-onset AD", "pmid": "8346443", "source": "Science", "year": "1993", "strength": "strong", "abstract": "The APOE epsilon-4 allele is associated with increased risk and earlier onset of Alzheimer's disease."}, {"claim": "APOE4 structure correctors show promise in AD models", "pmid": "35679413", "source": "Nat Struct Mol Biol", "year": "2022", "strength": "medium", "abstract": "Small molecule correctors of APOE4 structure rescue lipid m
[{"claim": "APOE reduction may impair beneficial lipid transport functions", "pmid": "31511426", "source": "Neuron", "year": "2019", "strength": "medium", "abstract": "Complete APOE reduction leads to synaptic deficits, suggesting therapeutic approaches must maintain baseline function."}, {"claim": "Multi-omics and experimental validation reveal the mechanism of DanxiaTiaoban decoction in treating atherosclerosis.", "pmid": "40916281", "source": "Phytomedicine", "year": "2025", "strength": "medi
Est. Cost: $2,000,000 Est. Timeline: 30 months
Target: SLC17A7 Disease: Alzheimer's Disease Type: mechanistic
SLC17A7 (also known as VGLUT1, vesicular glutamate transporter 1) shows significant downregulation (log2FC = -1.7) in the SEA-AD dataset, specifically in layer 3 and layer 5 excitatory neurons of the middle temporal gyrus. This reduction in the primary vesicular glutamate transporter marks early excitatory neuron vulnerability in Alzheimer's disease and points to synaptic transmission failure as a proximal cause of cognitive decline. ## Molecular Function of SLC17A7/VGLUT1 VGLUT1 is a transmembrane protein located on synaptic vesicle membranes that uses the proton electrochemical gradient generated by V-ATPase to transport glutamate from the cytoplasm into synaptic vesicles. It is the dominant vesicular glutamate transporter in the cerebral cortex and hippocampus, responsible for loading
[{"claim": "VGLUT1 protein levels decrease early in AD temporal cortex", "pmid": "30188896", "source": "Acta Neuropathol", "year": "2018", "strength": "medium", "abstract": "VGLUT1 protein is reduced in entorhinal and temporal cortex in early AD stages, correlating with cognitive decline."}, {"claim": "Layer 3 excitatory neurons are selectively vulnerable in AD", "pmid": "35879464", "source": "Nature", "year": "2022", "strength": "strong", "abstract": "Single-cell transcriptomics reveals selecti
[{"claim": "SLC17A7 downregulation may reflect neuron loss rather than dysfunction", "pmid": "33432242", "source": "Brain", "year": "2021", "strength": "medium", "abstract": "Apparent gene expression changes in bulk tissue may reflect altered cell composition rather than cell-intrinsic changes."}, {"claim": "Audiogenic kindling activates glutamatergic system in the hippocampus of rats with genetic predisposition to audiogenic seizures.", "pmid": "38325559", "source": "Brain Res", "year": "2024",
Est. Cost: $700,000 Est. Timeline: 24 months
Target: C1QA Disease: Alzheimer's Disease Type: mechanistic
C1QA, the initiating protein of the classical complement cascade, shows upregulation in the SEA-AD dataset with a layer-specific spatial gradient across cortical neurons in the middle temporal gyrus. This finding connects complement-mediated synaptic tagging to the selective vulnerability of specific cortical layers in Alzheimer's disease, revealing a previously underappreciated spatial dimension to complement-driven neurodegeneration. ## Molecular Mechanism of C1QA-Mediated Synaptic Elimination The classical complement cascade begins when C1q (composed of C1QA, C1QB, and C1QC subunits) binds to tagged synapses. In the developing brain, this process is essential for activity-dependent synaptic pruning — C1q marks weak or redundant synapses for elimination by microglia. In Alzheimer's dis
[{"claim": "C1q mediates synapse loss in AD mouse models", "pmid": "27033549", "source": "Science", "year": "2016", "strength": "strong", "abstract": "C1q protein accumulates on synapses before overt plaque deposition and mediates early synapse loss in AD models."}, {"claim": "Complement inhibition rescues synaptic density in AD models", "pmid": "31578290", "source": "Nat Neurosci", "year": "2019", "strength": "medium", "abstract": "Anti-C1q antibodies prevent synapse loss and cognitive decline
[{"claim": "Complement inhibition may impair amyloid plaque clearance", "pmid": "32268209", "source": "J Neuroinflammation", "year": "2020", "strength": "medium", "abstract": "C1q-dependent complement activation contributes to microglial amyloid phagocytosis."}, {"claim": "Microglia during development and aging.", "pmid": "23644076", "source": "Pharmacol Ther", "year": "2013", "strength": "medium", "abstract": "Microglia are critical nervous system-specific cells influencing brain development, m
Est. Cost: $1,800,000 Est. Timeline: 30 months
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