Description
The study shows cystatin-C binds amyloid oligomers and activates TREM2, but the molecular basis for this specific receptor activation is unclear. This mechanistic gap limits understanding of how to optimize cystatin-C therapeutic approaches and whether other receptors could be targeted.
Gap type: unexplained_observation Source paper: Peripheral cancer attenuates amyloid pathology in Alzheimer’s disease via cystatin-c activation of TREM2. (2026, Cell, PMID:41576952)
Evidence summary
{“resolution_pipeline”: “scidex.atlas.gap_closure_pipeline”, “task_id”: “f4f7b129-0f43-4c84-abd8-20d4e701842d”, “evaluated_at”: “2026-04-28T19:10:32.501747+00:00”, “resolution_summary”: “Resolved by hypothesis h-d083850487: TREM2-dependent microglial phagocytosis of tau seeds. Supporting evidence includes debate sess_SDA-2026-04-14-gap-pubmed-20260411-072446-a32fa49c.”, “match_counts”: {“hypothesis_matches”: 5, “debate_matches”: 5, “paper_matches”: 0}, “hypothesis_matches”: [{“id”: “h-d083850487”, “title”: “TREM2-dependent microglial phagocytosis of tau seeds”, “score”: 0.365, “reason”: “8 token overlaps; entity overlap: trem2”, “analysis_id”: “SDA-2026-04-26-gap-pubmed-20260410-150544-e3a2eab9-debate”, “target_gene”: “TREM2/Syk/PLCγ2”, “target_pathway”: null, “disease”: “neurodegeneration”, “composite_score”: 0.53, “confidence_score”: 0.5, “status”: “proposed”, “pubmed_evidence_ids”: [“26653636”, “29518356”, “29689295”, “36306735”, “36564824”]}, {“id”: “h-c58ac188fc”, “title”: “Enhancing Microglial Phagocytosis of Extracellular Tau via TREM2 Activation”, “score”: 0.258, “reason”: “21 token overlaps; entity overlap: trem2”, “analysis_id”: “SDA-2026-04-04-gap-tau-prion-spreading”, “target_gene”: “TREM2”, “target_pathway”: null, “disease”: “neuroscience”, “composite_score”: 0.770522, “confidence_score”: 0.82, “status”: “debated”, “pubmed_evidence_ids”: [“28803812”, “32403128”, “34429422”, “ClinicalTrials.gov”]}, {“id”: “h-f373e16bb108”, “title”: “EZH2-Mediated H3K27me3 Spreading in Senescent ALS Microglia Silences Neuroprotective Gene Programs — Reversible by EZH2 Inhibitors”, “score”: 0.258, “reason”: “12 token overlaps; entity overlap: trem2”, “analysis_id”: “SDA-2026-04-26-gap-20260425215446”, “target_gene”: “EZH2 (PRC2) → H3K27me3 silencing of BDNF, GRN, TREM2, MerTK”, “target_pathway”: null, “disease”: “ALS”, “composite_score”: 0.7136330000000001, “confidence_score”: 0.28, “status”: “proposed”, “pubmed_evidence_ids”: [“31048495”, “31202798”, “32553389”, “32933418”]}, {“id”: “h-aa1f5de5cd”, “title”: “TREM2 haploinsufficiency dysregulates microglial synaptic surveillance, switching from protective ‘disease-associated microglia’ to neurotoxic ‘inflammasome-active’ states”, “score”: 0.258, “reason”: “22 token overlaps; entity overlap: trem2”, “analysis_id”: “SDA-2026-04-02-gap-synaptic-pruning-microglia”, “target_gene”: “TREM2, TYROBP (DAP12), APOE”, “target_pathway”: null, “disease”: “neurodegeneration”, “composite_score”: 0.7, “confidence_score”: 0.22, “status”: “proposed”, “pubmed_evidence_ids”: [“26598730”, “27753624”, “28602351”, “28802038”, “29070674”]}, {“id”: “SDA-2026-04-02-gap-tau-prop-20260402003221-H002”, “title”: “TREM2-mediated microglial tau clearance enhancement”, “score”: 0.253, “reason”: “26 token overlaps; entity overlap: trem2”, “analysis_id”: “SDA-2026-04-04-gap-tau-prop-20260402003221”, “target_gene”: “TREM2”, “target_pathway”: “TREM2/TYROBP microglial signaling”, “disease”: “neurodegeneration”, “composite_score”: 0.780383, “confidence_score”: 0.665, “status”: “proposed”, “pubmed_evidence_ids”: [“24990881”, “28602351”, “28802038”, “31932797”, “33516818”]}], “debate_matches”: [{“id”: “sess_SDA-2026-04-14-gap-pubmed-20260411-072446-a32fa49c”, “title”: “The abstract shows TYROBP deficiency is neuroprotective despite being required for TREM2, CD33, and CR3 function - receptors associated with AD risk. This counterintuitive finding challenges current understanding of how these immune receptors contribute to AD pathogenesis.\n\nGap type: contradiction\nSource paper: Deficiency of TYROBP, an adapter protein for TREM2 and CR3 receptors, is neuroprotective in a mouse model of early Alzheimer’s pathology. (None, None, PMID:28612290)”, “score”: 0.555, “reason”: “11 token overlaps; entity overlap: pmid, trem2”, “analysis_id”: “SDA-2026-04-14-gap-pubmed-20260411-072446-a32fa49c”, “quality_score”: 0.56, “status”: “completed”, “target_artifact_id”: null, “target_artifact_type”: null}, {“id”: “sess_SDA-2026-04-15-gap-pubmed-20260411-090658-7651c1d2_20260416-033018”, “title”: “The abstract shows p53 is a central regulator of C9orf72-mediated neurodegeneration but doesn’t explain how poly(PR) specifically activates p53. Understanding this upstream trigger mechanism is critical for developing targeted therapeutic interventions.\n\nGap type: unexplained_observation\nSource paper: p53 is a central regulator driving neurodegeneration caused by C9orf72 poly(PR). (None, None, PMID:33482083)”, “score”: 0.488, “reason”: “12 token overlaps; entity overlap: pmid”, “analysis_id”: “SDA-2026-04-15-gap-pubmed-20260411-090658-7651c1d2”, “quality_score”: 0.61, “status”: “completed”, “target_artifact_id”: null, “target_artifact_type”: null}, {“id”: “sess_SDA-2026-04-13-gap-pubmed-20260410-145358-185db2c8_20260414-005137”, “title”: “The study shows homozygous R136S fully rescues APOE4-driven pathology while heterozygous provides only partial protection, but the mechanistic basis for this gene dosage effect is unexplained. Understanding this mechanism is critical for developing therapeutic strategies that could mimic R136S protection.\n\nGap type: unexplained_observation\nSource paper: The APOE-R136S mutation protects against APOE4-driven Tau pathology, neurodegeneration and neuroinflammation. (2023, Nature neuroscience, PMID:37957317)”, “score”: 0.471, “reason”: “13 token overlaps; entity overlap: pmid”, “analysis_id”: “SDA-2026-04-13-gap-pubmed-20260410-145358-185db2c8”, “quality_score”: 0.81, “status”: “completed”, “target_artifact_id”: null, “target_artifact_type”: null}, {“id”: “sess_SDA-2026-04-06-gap-pubmed-20260406-062118-e3613755_task_9aae8fc5”, “title”: “The study shows SPP1 from perivascular cells drives microglial synaptic engulfment, but the specific receptors, signaling pathways, and molecular cascades linking SPP1 to phagocytic gene expression remain undefined. Understanding this mechanism is critical for developing targeted therapeutics that could modulate pathological synaptic loss.\n\nGap type: unexplained_observation\nSource paper: Perivascular cells induce microglial phagocytic states and synaptic engulfment via SPP1 in mouse models of Alzheimer’s disease. (2023, Nat Neurosci, PMID:36747024)”, “score”: 0.459, “reason”: “12 token overlaps; entity overlap: pmid”, “analysis_id”: “SDA-2026-04-06-gap-pubmed-20260406-062118-e3613755”, “quality_score”: 0.704, “status”: “completed”, “target_artifact_id”: null, “target_artifact_type”: null}, {“id”: “sess_SDA-2026-04-08-gap-pubmed-20260406-062202-5c32c50a_task_9aae8fc5”, “title”: “AD patients with TDP-43 pathology show worse cognitive impairment, but how TDP-43 mechanistically contributes to this severity is unknown. Understanding this could identify TDP-43 as a therapeutic target for cognitive preservation in AD.\n\nGap type: unexplained_observation\nSource paper: TDP-43 Pathology in Alzheimer’s Disease. (2021, Mol Neurodegener, PMID:34930382)”, “score”: 0.458, “reason”: “10 token overlaps; entity overlap: pmid”, “analysis_id”: “SDA-2026-04-08-gap-pubmed-20260406-062202-5c32c50a”, “quality_score”: 0.734, “status”: “completed”, “target_artifact_id”: null, “target_artifact_type”: null}], “paper_matches”: []}