Version history

{
  "session_id": "sess_SDA-2026-04-12-gap-debate-20260410-112927-b4535f82_20260412-075030",
  "round_number": 1,
  "agent_persona": "persona-theorist",
  "agent_backend": "minimax/MiniMax-M2.7",
  "action": "propose",
  "content": "\n\n# Mechanistic Hypotheses: Curli Amyloid Trans-BBB Seeding of α-Synuclein Aggregation\n\n---\n\n## Hypothesis 1: LRP1-Mediated Curli Transcytosis Across the BBB\n\n**Title:** LRP1 receptor mediates curli amyloid transcytosis\n\n**Mechanism:** Curli fibrils (primarily CsgA monomers with conserved β-solenoid structure) bind to the low-density lipoprotein receptor-related protein 1 (LRP1) on brain microvascular endothelial cells. LRP1-mediated endocytosis packages curli into vesicles that traffic across the endothelial cytoplasm, releasing curli into the brain parenchyma via exocytosis at the abluminal membrane. Released curli directly templating α-synuclein (SNCA) monomer misfolding via cross-β-sheet complementarity.\n\n**Key Evidence:**\n- E. coli curli accelerate α-synuclein aggregation and dopaminergic neurodegeneration in M83 mice (PMID: 31101651)\n- LRP1 mediates transcytosis of other amyloid species (Aβ40, α-synuclein oligomers) across BBB (PMID: 23702984)\n\n**Testable Prediction:** siRNA knockdown of LRP1 in human iPSC-derived brain microvascular endothelial cells (BMVECs) will reduce transwell transport of purified FITC-labeled curli fibrils by >70% compared to non-targeting controls.\n\n**Target Gene/Protein:** LRP1 (LIPR1_HUMAN)\n\n---\n\n## Hypothesis 2: Cross-Seeding at the Neurovascular Unit via C3b Opsonization\n\n**Title:** Complement C3 deposits on curli enabling BBB crossing\n\n**Mechanism:** Systemic curli activates the classical complement cascade via C1q binding to curli fibrils (similar to Aβ recognition), leading to C3b opsonization. C3b-coated curli engages CR3 (CD11b/CD18) on infiltrating monocytes and neutrophils, hitchhiking across a compromised BBB. Alternatively, C3b binds CR3 on brain endothelial cells, triggering LRP1-independent transmigration. Within the brain, C3b-curli complexes directly nucleate α-synuclein fibrillization.\n\n**Key Evidence:**\n- Curli activate complement factor C3 in vitro and in vivo (PMID: 31249567)\n- C3 deficiency attenuates α-synuclein pathology in MOG35-80-immunized mice (PMID: 31953283)\n\n**Testable Prediction:** C3 knockout mice colonized with curli-producing E. coli will show reduced brain parenchymal curli (measured by RT-QuIC) and attenuated α-synuclein seeding compared to WT colonized mice.\n\n**Target Gene/Protein:** Complement C3 (CO3_HUMAN)\n\n---\n\n## Hypothesis 3: Bacterial Outer Membrane Vesicles Carry Curli Across the BBB\n\n**Title:** Curli-vesicle complexes penetrate BBB intact\n\n**Mechanism:** Curli fibers become incorporated into or",
  "tokens_used": "628"
}