{"gene":"A2M","run_date":"2026-06-09T22:02:35","timeline":{"discoveries":[{"year":2021,"finding":"Native human A2M forms a hollow tetrameric conformation composed of two crescent-shaped disulfide-bridged subunit dimers with a central hollow space and minimal inter-dimer interactions mediated mainly by linker (LNK) regions. Bait region cleavage induces intrasubunit domain repositioning and collapse of the tetramer into a compact conformation that encloses an interior protease-trapping cavity. A recombinant A2M with an engineered intersubunit disulfide in the LNK region confirmed predicted LNK–LNK interactions in native A2M.","method":"Negative stain electron microscopy, small-angle X-ray scattering (SAXS), cross-linking mass spectrometry (XL-MS), and recombinant A2M mutagenesis","journal":"Molecular & Cellular Proteomics","confidence":"High","confidence_rationale":"Tier 1 / Strong — multiple orthogonal structural methods (EM, SAXS, XL-MS) combined with functional mutagenesis in a single rigorous study","pmids":["33964423"],"is_preprint":false},{"year":2020,"finding":"Replacing the thiol ester motif (CGEQ) of A2M with a disulfide-forming sequence (CGEC) in mutant A2M Q975C produces a correctly folded, native-conformation tetramer that undergoes proteolysis-induced conformational collapse and retains LRP1-binding. However, the mutant had decreased trypsin-inhibitory capacity and was more susceptible to protease cleavage, demonstrating that thiol ester lysis (not proteolysis alone) contributes to the conformational change mechanism.","method":"Recombinant protein expression, mass spectrometry, electrophoretic mobility assay, protease inhibition assay, LRP1 binding assay","journal":"Biochemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro mutagenesis with multiple orthogonal functional readouts in a single study","pmids":["33301305"],"is_preprint":false},{"year":2022,"finding":"A2M binds and neutralizes IL-1β, blocking downstream NF-κB-induced catabolism in human chondrocytes. Immunoprecipitation confirmed direct A2M–IL-1β binding; fluorescence microscopy localized A2M to the cytoplasm after incubation. A2M reduced NF-κB, MMPs, and TNF-α levels and increased cartilage-protective gene expression (Col2, Smad4, aggrecan) in a dose-dependent manner.","method":"Immunoprecipitation, fluorescence microscopy (VivoTag-labeled A2M), Western blot, qRT-PCR in human chondrocyte cell line C28","journal":"Journal of Orthopaedic Research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal binding confirmed by IP plus multiple downstream functional readouts in a single lab study","pmids":["35451533"],"is_preprint":false},{"year":2017,"finding":"A2M modulates tumor cell adhesion, migration, and growth by inhibiting PI3K/AKT and SMAD signaling pathways, upregulating PTEN via downregulation of miR-21, and increasing CD29 and CD44 expression, without inducing EMT, as shown in vitro and in tumor xenografts.","method":"Cell-based assays (adhesion, migration, growth), Western blot for pathway components, miR-21 measurement, xenograft mouse model, transcriptome analysis of A2M-treated cells","journal":"PLoS One","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal in vitro and in vivo methods in a single lab study","pmids":["29281661"],"is_preprint":false},{"year":2015,"finding":"NR4A receptors (NOR-1, Nurr1, Nur77) directly transcriptionally activate the human A2M promoter via an NGFI-B response element (NBRE at -71/-64), increasing A2M expression and secretion in vascular smooth muscle cells (VSMCs). A2M upregulation by NR4A receptors partially mediates their inhibitory effect on MMP-2 and MMP-9 activity.","method":"Luciferase reporter assay, electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), lentiviral overexpression, NR4A knockdown, zymography, transgenic mouse model","journal":"Thrombosis and Haemostasis","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — direct promoter binding confirmed by EMSA and ChIP, functional consequence shown by multiple methods across in vitro and in vivo systems","pmids":["25809189"],"is_preprint":false},{"year":2017,"finding":"A2M interacts directly with MMP2 in aged rat kidney (confirmed by immunoprecipitation), and this interaction suppresses MMP2 enzymatic activity, leading to accumulation of ECM substrates including collagen type I and IV. STAT3 transcriptional activation (elevated by aging-associated cytokines) drives increased A2M expression, which promotes MMP2 trapping and ECM accumulation.","method":"Immunoprecipitation, immunohistochemistry, MMP2 activity assay (with and without A2M), RNA-seq, real-time PCR, Western blot in aged rat kidney","journal":"Oncotarget","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct interaction confirmed by Co-IP, functional MMP2 activity assay performed, upstream STAT3 regulation assessed, single lab","pmids":["29464020"],"is_preprint":false},{"year":2023,"finding":"A novel heterozygous missense mutation in A2M (c.1229A>C, p.N410T) eliminates an N-glycosylation site (Asn410) required for A2M activation and Aβ binding. Co-immunoprecipitation from patient plasma showed weakened interaction between mutant A2M and amyloid-β compared to wild-type, establishing a mechanism by which this mutation impairs Aβ clearance.","method":"Whole-exome sequencing, 3D protein structure prediction, co-immunoprecipitation from patient plasma","journal":"Frontiers in Neurology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — Co-IP from patient plasma combined with structural modeling; single case, single lab","pmids":["36698894"],"is_preprint":false},{"year":2003,"finding":"Plasma A2M from AD patients homozygous for the A2M intronic deletion showed normal subunit size, conformation, and protease inhibitory activity, but displayed markedly increased TGF-β1 binding and modestly elevated Aβ binding (in methylamine-activated form) compared to non-deletion patients, suggesting the deletion affects cytokine binding rather than protease trapping.","method":"SDS-PAGE, conformational assays, trypsin binding assay, TGF-β1 binding assay, Aβ binding assay on human plasma samples","journal":"Neurobiology of Disease","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple functional binding assays on human patient plasma samples, single lab, limited sample numbers","pmids":["14678766"],"is_preprint":false},{"year":2011,"finding":"Malondialdehyde-acetaldehyde (MAA) adduct formation on the A2M bait region (residues 620–792) and A2M N-terminal domain (residues 168–230) abrogates bait region binding to TGF-β1, trypsin, and elastase, and suppresses TGF-β1-induced NO production, indicating that chemical modification of these domains inactivates A2M's proteinase- and cytokine-trapping functions.","method":"In vitro MAA adduct formation, binding assays (trypsin, elastase, TGF-β1), NO production assay using mouse A2M recombinant fragments","journal":"FEBS Letters","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — in vitro biochemical assay with defined protein fragments, single lab, single paper","pmids":["21320498"],"is_preprint":false},{"year":2025,"finding":"A2M directly upregulates RhoA-GTPase activity in smooth muscle cells (SMCs) of the uterine spiral arteries, promoting SMC phenotype switching disorder that underlies preeclampsia pathology. Blocking A2M–LRP1 interaction with receptor-associated protein (RAP) reversed SMC phenotype switching and alleviated preeclampsia in a rat model. LC-MS/MS and Co-IP confirmed A2M interaction with components of the RhoA-GTPase pathway.","method":"Co-immunoprecipitation, LC-MS/MS proteomics, proteomic sequencing of A2M-overexpressing rat placenta, RAP-mediated A2M–LRP1 blockade in rat preeclampsia model, AAV knockdown, cytological and explant experiments","journal":"Cell Communication and Signaling","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP and MS identified interaction, multiple orthogonal in vivo experiments, single lab","pmids":["39994728"],"is_preprint":false},{"year":2030,"finding":"A2M silencing (CRISPR/Cas9) in STAD cells decreased cell viability, migration, invasion, and colony formation, and reduced expression of vimentin, indicating that A2M promotes epithelial-mesenchymal transition (EMT) in stomach adenocarcinoma through upregulation of vimentin.","method":"CRISPR/Cas9 knockdown, cell viability assay, migration/invasion (Transwell), colony formation, Western blot for vimentin in STAD cell lines","journal":"Translational Cancer Research","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean CRISPR KO with defined cellular phenotype, single lab, single paper","pmids":["42180958"],"is_preprint":false},{"year":2023,"finding":"A2M silencing in human bone marrow mesenchymal stromal cells (BM-MSCs) induced proliferation and skewed lineage differentiation toward adipogenesis at the expense of osteogenesis, recapitulating aspects of age-induced stem cell dysfunction and implying a role for A2M as a regulator of skeletal stem/progenitor cell fate.","method":"RNA-seq in mouse SSPCs, siRNA loss-of-function in human BM-MSCs, differentiation assays, FACS, micro-CT","journal":"Frontiers in Cell and Developmental Biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — loss-of-function with defined lineage bifurcation phenotype, supported by in vivo RNA-seq, single lab","pmids":["37965574"],"is_preprint":false},{"year":2014,"finding":"A chromosomal translocation t(2;12)(p23;p13) generates a novel A2M–ALK chimeric fusion gene in which exon 22 of A2M is fused to exon 19 of ALK, identified in a fetal lung interstitial tumor (FLIT). This fusion results in ALK expression in mesenchymal tumor cells, linking A2M as an ALK fusion partner with potential oncogenic signaling.","method":"Karyotyping (FISH break-apart), 5'-RACE, RT-PCR, genomic sequencing confirming breakpoint in A2M intron 22 and ALK intron 18","journal":"Genes, Chromosomes and Cancer","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct molecular identification of fusion transcript and genomic breakpoint by multiple methods, single case","pmids":["24965693"],"is_preprint":false},{"year":2024,"finding":"In sea cucumber (Apostichopus japonicus), the A2M thioester domain (TED) binds directly to pathogens and causes bacterial aggregation, while the receptor-binding domain (RBD) interacts with GRP78 (AjGRP78), which then accelerates lysosomal degradation of bacteria by facilitating cytoskeletal polymerization and rearrangement, promoting phagocytosis.","method":"Recombinant domain cloning, co-immunoprecipitation, phagocytosis assay, lysosomal degradation assay, cytoskeleton imaging in sea cucumber coelomocytes","journal":"International Journal of Biological Macromolecules","confidence":"Low","confidence_rationale":"Tier 3 / Weak — invertebrate ortholog study (sea cucumber), single Co-IP and domain binding assays, single lab; distant from mammalian A2M mechanism","pmids":["38513908"],"is_preprint":false},{"year":2023,"finding":"LINC00612 enhances binding of phosphorylated STAT3 (p-STAT3) to the A2M promoter, thereby increasing A2M expression in bronchial epithelial cells (BEAS-2B). RNA antisense purification and ChIP confirmed the interaction between LINC00612, STAT3, and the A2M promoter. A2M knockdown attenuated the anti-apoptotic and anti-inflammatory effects of LINC00612 overexpression.","method":"RNA antisense purification, chromatin immunoprecipitation (ChIP), overexpression/knockdown in BEAS-2B cells, flow cytometry apoptosis assay","journal":"PeerJ","confidence":"Low","confidence_rationale":"Tier 3 / Weak — lncRNA-mediated mechanism study; mechanistic finding about A2M promoter regulation is secondary to lncRNA focus, single lab","pmids":["36883061"],"is_preprint":false},{"year":2025,"finding":"In SH-SY5Y neuroblastoma cells exposed to pesticides (Aldicarb and Chlorpyrifos), exogenous A2M upregulates anti-apoptotic proteins Bcl-2 and Nrf2 while downregulating pro-apoptotic markers Bax, Caspase-3, and Caspase-9. A2M also enhanced mitochondrial complex I and III activity and reduced ROS and inflammatory cytokine-induced DNA damage.","method":"Western blot profiling, biochemical mitochondrial enzyme activity assays, ROS measurement in pesticide-exposed SH-SY5Y neuroblastoma cells","journal":"bioRxiv (preprint)","confidence":"Low","confidence_rationale":"Tier 3 / Weak — preprint, single method type per endpoint, no genetic rescue or mutagenesis, single lab","pmids":["bio_10.1101_2025.06.27.661925"],"is_preprint":true},{"year":2025,"finding":"Exosome-delivered A2M protein reprogrammed M1 macrophage polarization toward M2 (decreasing TNF-α and IL-6, increasing CD206 and Arg-1) through IL-4 signaling activation, and enhanced osteogenic differentiation of BMSCs (upregulating RUNX2, ALP, OCN). shRNA-mediated IL-4 knockdown abolished these effects, confirming pathway specificity.","method":"Engineered exosome delivery of A2M, transcriptomic/proteomic profiling, shRNA IL-4 knockdown, ELISA, Western blot, rat ONFH model with micro-CT","journal":"Cell Death Discovery","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — pathway specificity confirmed by shRNA rescue, multiple orthogonal methods, single lab","pmids":["41203607"],"is_preprint":false}],"current_model":"Human A2M is a secreted tetrameric pan-protease inhibitor that operates through a conformational trap mechanism: in its native hollow tetrameric form, bait region cleavage by a protease (aided by thiol ester lysis) triggers collapse to a compact conformation that encloses and irreversibly traps the protease; the collapsed form then binds LRP1 for receptor-mediated clearance. Beyond protease inhibition, A2M directly binds and neutralizes cytokines and growth factors (including IL-1β, TGF-β1, and Aβ) via its bait region, and its expression is transcriptionally activated by NR4A receptors and STAT3 through defined promoter elements, allowing A2M to modulate downstream signaling pathways including NF-κB, PI3K/AKT, SMAD, and RhoA-GTPase in contexts ranging from cartilage homeostasis to vascular remodeling and preeclampsia."},"narrative":{"mechanistic_narrative":"A2M is a secreted pan-protease inhibitor that operates through a conformational trap: native A2M assembles as a hollow tetramer of two crescent-shaped disulfide-bridged subunit dimers held together largely by linker (LNK)-region contacts, and bait-region cleavage triggers intrasubunit domain repositioning that collapses the tetramer into a compact, protease-enclosing conformation [PMID:33964423]. This conformational change depends not on proteolysis alone but on lysis of the internal thiol ester, and the collapsed form retains LRP1-binding for receptor-mediated clearance [PMID:33301305]. Beyond trapping proteases, A2M directly binds and neutralizes cytokines and growth factors: it captures IL-1β to block downstream NF-κB-driven catabolism in chondrocytes [PMID:35451533], binds TGF-β1 and amyloid-β through its bait region and N-terminal domain [PMID:14678766, PMID:21320498], and an N-glycosylation-site mutation (p.N410T) that weakens A2M–Aβ interaction has been identified in Alzheimer's disease [PMID:36698894]. A2M also sequesters and inhibits matrix metalloproteinases (MMP2), driving extracellular matrix accumulation [PMID:29464020]. Its expression is transcriptionally activated through defined promoter elements by NR4A receptors via an NGFI-B response element in vascular smooth muscle cells [PMID:25809189] and by STAT3 [PMID:29464020], and through these inputs A2M modulates PI3K/AKT, SMAD, and RhoA-GTPase signaling in contexts spanning tumor adhesion and migration [PMID:29281661], uterine spiral-artery smooth-muscle phenotype switching in preeclampsia [PMID:39994728], and skeletal stem/progenitor cell fate [PMID:37965574].","teleology":[{"year":2003,"claim":"Established that an AD-associated A2M intronic deletion alters cytokine binding rather than the canonical protease-trap function, separating A2M's two activities.","evidence":"SDS-PAGE, conformational and binding assays on plasma from deletion-homozygous AD patients","pmids":["14678766"],"confidence":"Medium","gaps":["Mechanism connecting the intronic deletion to altered TGF-β1/Aβ binding not defined","Small sample size","No structural basis for differential binding"]},{"year":2011,"claim":"Mapped the protein regions required for A2M's dual proteinase- and cytokine-trapping, showing bait region and N-terminal domain modification inactivates both functions.","evidence":"In vitro MAA adduct formation and binding/NO assays using recombinant mouse A2M fragments","pmids":["21320498"],"confidence":"Medium","gaps":["Uses mouse fragments, not intact human tetramer","Physiological relevance of MAA adduction unclear","Single lab"]},{"year":2015,"claim":"Identified a direct transcriptional input controlling A2M, showing NR4A receptors bind the A2M promoter and link its expression to MMP regulation in vascular cells.","evidence":"Luciferase, EMSA, ChIP, overexpression/knockdown, zymography, transgenic mouse in VSMCs","pmids":["25809189"],"confidence":"High","gaps":["Other promoter regulators not surveyed","Extent of MMP suppression mediated by A2M only partial"]},{"year":2017,"claim":"Linked A2M to intracellular signaling control, showing it suppresses tumor cell PI3K/AKT and SMAD pathways via miR-21/PTEN without inducing EMT.","evidence":"In vitro adhesion/migration assays, Western blot, miR-21 measurement, xenografts","pmids":["29281661"],"confidence":"Medium","gaps":["Receptor/mechanism coupling extracellular A2M to miR-21 not defined","No direct binding partner identified"]},{"year":2017,"claim":"Demonstrated A2M directly traps and inhibits MMP2 and is driven by STAT3, establishing an aging-associated A2M–MMP2–ECM accumulation axis.","evidence":"Co-IP, MMP2 activity assay, RNA-seq, IHC in aged rat kidney","pmids":["29464020"],"confidence":"Medium","gaps":["Co-IP not reciprocally validated in human tissue","Whether trapping uses the canonical conformational mechanism unconfirmed"]},{"year":2020,"claim":"Resolved the mechanistic basis of the conformational trap, showing thiol ester lysis (not proteolysis alone) drives the collapse while LRP1-binding is retained.","evidence":"Recombinant Q975C thiol ester mutant with protease inhibition and LRP1 binding assays","pmids":["33301305"],"confidence":"High","gaps":["Quantitative coupling between thiol ester lysis and bait cleavage kinetics not fully defined"]},{"year":2021,"claim":"Defined the architecture of the native trap, revealing the hollow LNK-linked tetramer and the collapse geometry that encloses captured protease.","evidence":"Negative-stain EM, SAXS, XL-MS, and engineered intersubunit disulfide mutagenesis","pmids":["33964423"],"confidence":"High","gaps":["No high-resolution atomic structure of trapped protease complex","Conformational intermediates not captured"]},{"year":2022,"claim":"Showed A2M directly binds IL-1β to block NF-κB catabolic signaling, extending the cytokine-neutralizing role to cartilage homeostasis.","evidence":"Reciprocal IP, fluorescence microscopy, Western blot, qRT-PCR in human C28 chondrocytes","pmids":["35451533"],"confidence":"Medium","gaps":["Whether IL-1β capture uses bait region or trap mechanism not resolved","Cytoplasmic localization of A2M not mechanistically explained"]},{"year":2023,"claim":"Provided patient-level evidence linking A2M to Aβ clearance, showing an N-glycosylation-eliminating mutation weakens A2M–Aβ binding.","evidence":"Whole-exome sequencing, structure prediction, Co-IP from patient plasma","pmids":["36698894"],"confidence":"Medium","gaps":["Single case","Causal contribution to disease not established by rescue","Co-IP not reciprocally validated"]},{"year":2023,"claim":"Implicated A2M as a regulator of stem/progenitor fate, with loss biasing mesenchymal cells toward adipogenesis over osteogenesis.","evidence":"siRNA loss-of-function in human BM-MSCs, differentiation assays, in vivo RNA-seq","pmids":["37965574"],"confidence":"Medium","gaps":["Molecular pathway coupling A2M to lineage choice undefined","No rescue with recombinant A2M"]},{"year":2025,"claim":"Connected A2M to RhoA-GTPase-driven smooth-muscle phenotype switching in preeclampsia, with LRP1 blockade reversing the phenotype.","evidence":"Co-IP, LC-MS/MS, AAV knockdown, RAP-mediated LRP1 blockade in rat preeclampsia model","pmids":["39994728"],"confidence":"Medium","gaps":["Direct vs indirect interaction with RhoA pathway components unresolved","Human validation limited"]},{"year":2025,"claim":"Showed A2M can reprogram macrophage polarization toward M2 and promote osteogenesis through IL-4 signaling.","evidence":"Exosome-delivered A2M, shRNA IL-4 rescue, rat ONFH model","pmids":["41203607"],"confidence":"Medium","gaps":["How A2M activates IL-4 signaling mechanistically unknown","Single lab"]},{"year":null,"claim":"It remains unresolved how A2M's extracellular conformational trap and LRP1 clearance mechanistically couple to the diverse intracellular signaling outcomes (NF-κB, PI3K/AKT, SMAD, RhoA, IL-4) attributed to it across tissues.","evidence":"","pmids":[],"confidence":"Low","gaps":["No unifying receptor/signaling model linking A2M binding to downstream pathway modulation","Most signaling roles shown in single labs without reciprocal mechanistic validation"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,1,2,5,8]},{"term_id":"GO:0140313","term_label":"molecular sequestering activity","supporting_discovery_ids":[0,1,5]}],"localization":[{"term_id":"GO:0005576","term_label":"extracellular region","supporting_discovery_ids":[4,7]}],"pathway":[{"term_id":"R-HSA-1474244","term_label":"Extracellular matrix organization","supporting_discovery_ids":[5]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[3,9]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[4,5]}],"complexes":[],"partners":["LRP1","IL1B","TGFB1","MMP2","ALK"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P01023","full_name":"Alpha-2-macroglobulin","aliases":["C3 and PZP-like alpha-2-macroglobulin domain-containing protein 5"],"length_aa":1474,"mass_kda":163.3,"function":"Is able to inhibit all four classes of proteinases by a unique 'trapping' mechanism. This protein has a peptide stretch, called the 'bait region' which contains specific cleavage sites for different proteinases. When a proteinase cleaves the bait region, a conformational change is induced in the protein which traps the proteinase. The entrapped enzyme remains active against low molecular weight substrates (activity against high molecular weight substrates is greatly reduced). 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  \"year\": 2021,\n      \"finding\": \"Native human A2M forms a hollow tetrameric conformation composed of two crescent-shaped disulfide-bridged subunit dimers with a central hollow space and minimal inter-dimer interactions mediated mainly by linker (LNK) regions. Bait region cleavage induces intrasubunit domain repositioning and collapse of the tetramer into a compact conformation that encloses an interior protease-trapping cavity. A recombinant A2M with an engineered intersubunit disulfide in the LNK region confirmed predicted LNK–LNK interactions in native A2M.\",\n      \"method\": \"Negative stain electron microscopy, small-angle X-ray scattering (SAXS), cross-linking mass spectrometry (XL-MS), and recombinant A2M mutagenesis\",\n      \"journal\": \"Molecular & Cellular Proteomics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — multiple orthogonal structural methods (EM, SAXS, XL-MS) combined with functional mutagenesis in a single rigorous study\",\n      \"pmids\": [\"33964423\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Replacing the thiol ester motif (CGEQ) of A2M with a disulfide-forming sequence (CGEC) in mutant A2M Q975C produces a correctly folded, native-conformation tetramer that undergoes proteolysis-induced conformational collapse and retains LRP1-binding. However, the mutant had decreased trypsin-inhibitory capacity and was more susceptible to protease cleavage, demonstrating that thiol ester lysis (not proteolysis alone) contributes to the conformational change mechanism.\",\n      \"method\": \"Recombinant protein expression, mass spectrometry, electrophoretic mobility assay, protease inhibition assay, LRP1 binding assay\",\n      \"journal\": \"Biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro mutagenesis with multiple orthogonal functional readouts in a single study\",\n      \"pmids\": [\"33301305\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"A2M binds and neutralizes IL-1β, blocking downstream NF-κB-induced catabolism in human chondrocytes. Immunoprecipitation confirmed direct A2M–IL-1β binding; fluorescence microscopy localized A2M to the cytoplasm after incubation. A2M reduced NF-κB, MMPs, and TNF-α levels and increased cartilage-protective gene expression (Col2, Smad4, aggrecan) in a dose-dependent manner.\",\n      \"method\": \"Immunoprecipitation, fluorescence microscopy (VivoTag-labeled A2M), Western blot, qRT-PCR in human chondrocyte cell line C28\",\n      \"journal\": \"Journal of Orthopaedic Research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal binding confirmed by IP plus multiple downstream functional readouts in a single lab study\",\n      \"pmids\": [\"35451533\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"A2M modulates tumor cell adhesion, migration, and growth by inhibiting PI3K/AKT and SMAD signaling pathways, upregulating PTEN via downregulation of miR-21, and increasing CD29 and CD44 expression, without inducing EMT, as shown in vitro and in tumor xenografts.\",\n      \"method\": \"Cell-based assays (adhesion, migration, growth), Western blot for pathway components, miR-21 measurement, xenograft mouse model, transcriptome analysis of A2M-treated cells\",\n      \"journal\": \"PLoS One\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal in vitro and in vivo methods in a single lab study\",\n      \"pmids\": [\"29281661\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"NR4A receptors (NOR-1, Nurr1, Nur77) directly transcriptionally activate the human A2M promoter via an NGFI-B response element (NBRE at -71/-64), increasing A2M expression and secretion in vascular smooth muscle cells (VSMCs). A2M upregulation by NR4A receptors partially mediates their inhibitory effect on MMP-2 and MMP-9 activity.\",\n      \"method\": \"Luciferase reporter assay, electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), lentiviral overexpression, NR4A knockdown, zymography, transgenic mouse model\",\n      \"journal\": \"Thrombosis and Haemostasis\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — direct promoter binding confirmed by EMSA and ChIP, functional consequence shown by multiple methods across in vitro and in vivo systems\",\n      \"pmids\": [\"25809189\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"A2M interacts directly with MMP2 in aged rat kidney (confirmed by immunoprecipitation), and this interaction suppresses MMP2 enzymatic activity, leading to accumulation of ECM substrates including collagen type I and IV. STAT3 transcriptional activation (elevated by aging-associated cytokines) drives increased A2M expression, which promotes MMP2 trapping and ECM accumulation.\",\n      \"method\": \"Immunoprecipitation, immunohistochemistry, MMP2 activity assay (with and without A2M), RNA-seq, real-time PCR, Western blot in aged rat kidney\",\n      \"journal\": \"Oncotarget\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct interaction confirmed by Co-IP, functional MMP2 activity assay performed, upstream STAT3 regulation assessed, single lab\",\n      \"pmids\": [\"29464020\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"A novel heterozygous missense mutation in A2M (c.1229A>C, p.N410T) eliminates an N-glycosylation site (Asn410) required for A2M activation and Aβ binding. Co-immunoprecipitation from patient plasma showed weakened interaction between mutant A2M and amyloid-β compared to wild-type, establishing a mechanism by which this mutation impairs Aβ clearance.\",\n      \"method\": \"Whole-exome sequencing, 3D protein structure prediction, co-immunoprecipitation from patient plasma\",\n      \"journal\": \"Frontiers in Neurology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — Co-IP from patient plasma combined with structural modeling; single case, single lab\",\n      \"pmids\": [\"36698894\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Plasma A2M from AD patients homozygous for the A2M intronic deletion showed normal subunit size, conformation, and protease inhibitory activity, but displayed markedly increased TGF-β1 binding and modestly elevated Aβ binding (in methylamine-activated form) compared to non-deletion patients, suggesting the deletion affects cytokine binding rather than protease trapping.\",\n      \"method\": \"SDS-PAGE, conformational assays, trypsin binding assay, TGF-β1 binding assay, Aβ binding assay on human plasma samples\",\n      \"journal\": \"Neurobiology of Disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple functional binding assays on human patient plasma samples, single lab, limited sample numbers\",\n      \"pmids\": [\"14678766\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Malondialdehyde-acetaldehyde (MAA) adduct formation on the A2M bait region (residues 620–792) and A2M N-terminal domain (residues 168–230) abrogates bait region binding to TGF-β1, trypsin, and elastase, and suppresses TGF-β1-induced NO production, indicating that chemical modification of these domains inactivates A2M's proteinase- and cytokine-trapping functions.\",\n      \"method\": \"In vitro MAA adduct formation, binding assays (trypsin, elastase, TGF-β1), NO production assay using mouse A2M recombinant fragments\",\n      \"journal\": \"FEBS Letters\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — in vitro biochemical assay with defined protein fragments, single lab, single paper\",\n      \"pmids\": [\"21320498\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"A2M directly upregulates RhoA-GTPase activity in smooth muscle cells (SMCs) of the uterine spiral arteries, promoting SMC phenotype switching disorder that underlies preeclampsia pathology. Blocking A2M–LRP1 interaction with receptor-associated protein (RAP) reversed SMC phenotype switching and alleviated preeclampsia in a rat model. LC-MS/MS and Co-IP confirmed A2M interaction with components of the RhoA-GTPase pathway.\",\n      \"method\": \"Co-immunoprecipitation, LC-MS/MS proteomics, proteomic sequencing of A2M-overexpressing rat placenta, RAP-mediated A2M–LRP1 blockade in rat preeclampsia model, AAV knockdown, cytological and explant experiments\",\n      \"journal\": \"Cell Communication and Signaling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP and MS identified interaction, multiple orthogonal in vivo experiments, single lab\",\n      \"pmids\": [\"39994728\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2030,\n      \"finding\": \"A2M silencing (CRISPR/Cas9) in STAD cells decreased cell viability, migration, invasion, and colony formation, and reduced expression of vimentin, indicating that A2M promotes epithelial-mesenchymal transition (EMT) in stomach adenocarcinoma through upregulation of vimentin.\",\n      \"method\": \"CRISPR/Cas9 knockdown, cell viability assay, migration/invasion (Transwell), colony formation, Western blot for vimentin in STAD cell lines\",\n      \"journal\": \"Translational Cancer Research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean CRISPR KO with defined cellular phenotype, single lab, single paper\",\n      \"pmids\": [\"42180958\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"A2M silencing in human bone marrow mesenchymal stromal cells (BM-MSCs) induced proliferation and skewed lineage differentiation toward adipogenesis at the expense of osteogenesis, recapitulating aspects of age-induced stem cell dysfunction and implying a role for A2M as a regulator of skeletal stem/progenitor cell fate.\",\n      \"method\": \"RNA-seq in mouse SSPCs, siRNA loss-of-function in human BM-MSCs, differentiation assays, FACS, micro-CT\",\n      \"journal\": \"Frontiers in Cell and Developmental Biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — loss-of-function with defined lineage bifurcation phenotype, supported by in vivo RNA-seq, single lab\",\n      \"pmids\": [\"37965574\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"A chromosomal translocation t(2;12)(p23;p13) generates a novel A2M–ALK chimeric fusion gene in which exon 22 of A2M is fused to exon 19 of ALK, identified in a fetal lung interstitial tumor (FLIT). This fusion results in ALK expression in mesenchymal tumor cells, linking A2M as an ALK fusion partner with potential oncogenic signaling.\",\n      \"method\": \"Karyotyping (FISH break-apart), 5'-RACE, RT-PCR, genomic sequencing confirming breakpoint in A2M intron 22 and ALK intron 18\",\n      \"journal\": \"Genes, Chromosomes and Cancer\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct molecular identification of fusion transcript and genomic breakpoint by multiple methods, single case\",\n      \"pmids\": [\"24965693\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"In sea cucumber (Apostichopus japonicus), the A2M thioester domain (TED) binds directly to pathogens and causes bacterial aggregation, while the receptor-binding domain (RBD) interacts with GRP78 (AjGRP78), which then accelerates lysosomal degradation of bacteria by facilitating cytoskeletal polymerization and rearrangement, promoting phagocytosis.\",\n      \"method\": \"Recombinant domain cloning, co-immunoprecipitation, phagocytosis assay, lysosomal degradation assay, cytoskeleton imaging in sea cucumber coelomocytes\",\n      \"journal\": \"International Journal of Biological Macromolecules\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — invertebrate ortholog study (sea cucumber), single Co-IP and domain binding assays, single lab; distant from mammalian A2M mechanism\",\n      \"pmids\": [\"38513908\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"LINC00612 enhances binding of phosphorylated STAT3 (p-STAT3) to the A2M promoter, thereby increasing A2M expression in bronchial epithelial cells (BEAS-2B). RNA antisense purification and ChIP confirmed the interaction between LINC00612, STAT3, and the A2M promoter. A2M knockdown attenuated the anti-apoptotic and anti-inflammatory effects of LINC00612 overexpression.\",\n      \"method\": \"RNA antisense purification, chromatin immunoprecipitation (ChIP), overexpression/knockdown in BEAS-2B cells, flow cytometry apoptosis assay\",\n      \"journal\": \"PeerJ\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — lncRNA-mediated mechanism study; mechanistic finding about A2M promoter regulation is secondary to lncRNA focus, single lab\",\n      \"pmids\": [\"36883061\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"In SH-SY5Y neuroblastoma cells exposed to pesticides (Aldicarb and Chlorpyrifos), exogenous A2M upregulates anti-apoptotic proteins Bcl-2 and Nrf2 while downregulating pro-apoptotic markers Bax, Caspase-3, and Caspase-9. A2M also enhanced mitochondrial complex I and III activity and reduced ROS and inflammatory cytokine-induced DNA damage.\",\n      \"method\": \"Western blot profiling, biochemical mitochondrial enzyme activity assays, ROS measurement in pesticide-exposed SH-SY5Y neuroblastoma cells\",\n      \"journal\": \"bioRxiv (preprint)\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — preprint, single method type per endpoint, no genetic rescue or mutagenesis, single lab\",\n      \"pmids\": [\"bio_10.1101_2025.06.27.661925\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Exosome-delivered A2M protein reprogrammed M1 macrophage polarization toward M2 (decreasing TNF-α and IL-6, increasing CD206 and Arg-1) through IL-4 signaling activation, and enhanced osteogenic differentiation of BMSCs (upregulating RUNX2, ALP, OCN). shRNA-mediated IL-4 knockdown abolished these effects, confirming pathway specificity.\",\n      \"method\": \"Engineered exosome delivery of A2M, transcriptomic/proteomic profiling, shRNA IL-4 knockdown, ELISA, Western blot, rat ONFH model with micro-CT\",\n      \"journal\": \"Cell Death Discovery\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — pathway specificity confirmed by shRNA rescue, multiple orthogonal methods, single lab\",\n      \"pmids\": [\"41203607\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"Human A2M is a secreted tetrameric pan-protease inhibitor that operates through a conformational trap mechanism: in its native hollow tetrameric form, bait region cleavage by a protease (aided by thiol ester lysis) triggers collapse to a compact conformation that encloses and irreversibly traps the protease; the collapsed form then binds LRP1 for receptor-mediated clearance. Beyond protease inhibition, A2M directly binds and neutralizes cytokines and growth factors (including IL-1β, TGF-β1, and Aβ) via its bait region, and its expression is transcriptionally activated by NR4A receptors and STAT3 through defined promoter elements, allowing A2M to modulate downstream signaling pathways including NF-κB, PI3K/AKT, SMAD, and RhoA-GTPase in contexts ranging from cartilage homeostasis to vascular remodeling and preeclampsia.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"A2M is a secreted pan-protease inhibitor that operates through a conformational trap: native A2M assembles as a hollow tetramer of two crescent-shaped disulfide-bridged subunit dimers held together largely by linker (LNK)-region contacts, and bait-region cleavage triggers intrasubunit domain repositioning that collapses the tetramer into a compact, protease-enclosing conformation [#0]. This conformational change depends not on proteolysis alone but on lysis of the internal thiol ester, and the collapsed form retains LRP1-binding for receptor-mediated clearance [#1]. Beyond trapping proteases, A2M directly binds and neutralizes cytokines and growth factors: it captures IL-1β to block downstream NF-κB-driven catabolism in chondrocytes [#2], binds TGF-β1 and amyloid-β through its bait region and N-terminal domain [#7, #8], and an N-glycosylation-site mutation (p.N410T) that weakens A2M–Aβ interaction has been identified in Alzheimer's disease [#6]. A2M also sequesters and inhibits matrix metalloproteinases (MMP2), driving extracellular matrix accumulation [#5]. Its expression is transcriptionally activated through defined promoter elements by NR4A receptors via an NGFI-B response element in vascular smooth muscle cells [#4] and by STAT3 [#5], and through these inputs A2M modulates PI3K/AKT, SMAD, and RhoA-GTPase signaling in contexts spanning tumor adhesion and migration [#3], uterine spiral-artery smooth-muscle phenotype switching in preeclampsia [#9], and skeletal stem/progenitor cell fate [#11].\",\n  \"teleology\": [\n    {\n      \"year\": 2003,\n      \"claim\": \"Established that an AD-associated A2M intronic deletion alters cytokine binding rather than the canonical protease-trap function, separating A2M's two activities.\",\n      \"evidence\": \"SDS-PAGE, conformational and binding assays on plasma from deletion-homozygous AD patients\",\n      \"pmids\": [\"14678766\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism connecting the intronic deletion to altered TGF-β1/Aβ binding not defined\", \"Small sample size\", \"No structural basis for differential binding\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Mapped the protein regions required for A2M's dual proteinase- and cytokine-trapping, showing bait region and N-terminal domain modification inactivates both functions.\",\n      \"evidence\": \"In vitro MAA adduct formation and binding/NO assays using recombinant mouse A2M fragments\",\n      \"pmids\": [\"21320498\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Uses mouse fragments, not intact human tetramer\", \"Physiological relevance of MAA adduction unclear\", \"Single lab\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Identified a direct transcriptional input controlling A2M, showing NR4A receptors bind the A2M promoter and link its expression to MMP regulation in vascular cells.\",\n      \"evidence\": \"Luciferase, EMSA, ChIP, overexpression/knockdown, zymography, transgenic mouse in VSMCs\",\n      \"pmids\": [\"25809189\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Other promoter regulators not surveyed\", \"Extent of MMP suppression mediated by A2M only partial\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Linked A2M to intracellular signaling control, showing it suppresses tumor cell PI3K/AKT and SMAD pathways via miR-21/PTEN without inducing EMT.\",\n      \"evidence\": \"In vitro adhesion/migration assays, Western blot, miR-21 measurement, xenografts\",\n      \"pmids\": [\"29281661\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Receptor/mechanism coupling extracellular A2M to miR-21 not defined\", \"No direct binding partner identified\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Demonstrated A2M directly traps and inhibits MMP2 and is driven by STAT3, establishing an aging-associated A2M–MMP2–ECM accumulation axis.\",\n      \"evidence\": \"Co-IP, MMP2 activity assay, RNA-seq, IHC in aged rat kidney\",\n      \"pmids\": [\"29464020\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Co-IP not reciprocally validated in human tissue\", \"Whether trapping uses the canonical conformational mechanism unconfirmed\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Resolved the mechanistic basis of the conformational trap, showing thiol ester lysis (not proteolysis alone) drives the collapse while LRP1-binding is retained.\",\n      \"evidence\": \"Recombinant Q975C thiol ester mutant with protease inhibition and LRP1 binding assays\",\n      \"pmids\": [\"33301305\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Quantitative coupling between thiol ester lysis and bait cleavage kinetics not fully defined\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Defined the architecture of the native trap, revealing the hollow LNK-linked tetramer and the collapse geometry that encloses captured protease.\",\n      \"evidence\": \"Negative-stain EM, SAXS, XL-MS, and engineered intersubunit disulfide mutagenesis\",\n      \"pmids\": [\"33964423\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No high-resolution atomic structure of trapped protease complex\", \"Conformational intermediates not captured\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Showed A2M directly binds IL-1β to block NF-κB catabolic signaling, extending the cytokine-neutralizing role to cartilage homeostasis.\",\n      \"evidence\": \"Reciprocal IP, fluorescence microscopy, Western blot, qRT-PCR in human C28 chondrocytes\",\n      \"pmids\": [\"35451533\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether IL-1β capture uses bait region or trap mechanism not resolved\", \"Cytoplasmic localization of A2M not mechanistically explained\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Provided patient-level evidence linking A2M to Aβ clearance, showing an N-glycosylation-eliminating mutation weakens A2M–Aβ binding.\",\n      \"evidence\": \"Whole-exome sequencing, structure prediction, Co-IP from patient plasma\",\n      \"pmids\": [\"36698894\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single case\", \"Causal contribution to disease not established by rescue\", \"Co-IP not reciprocally validated\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Implicated A2M as a regulator of stem/progenitor fate, with loss biasing mesenchymal cells toward adipogenesis over osteogenesis.\",\n      \"evidence\": \"siRNA loss-of-function in human BM-MSCs, differentiation assays, in vivo RNA-seq\",\n      \"pmids\": [\"37965574\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular pathway coupling A2M to lineage choice undefined\", \"No rescue with recombinant A2M\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Connected A2M to RhoA-GTPase-driven smooth-muscle phenotype switching in preeclampsia, with LRP1 blockade reversing the phenotype.\",\n      \"evidence\": \"Co-IP, LC-MS/MS, AAV knockdown, RAP-mediated LRP1 blockade in rat preeclampsia model\",\n      \"pmids\": [\"39994728\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct vs indirect interaction with RhoA pathway components unresolved\", \"Human validation limited\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Showed A2M can reprogram macrophage polarization toward M2 and promote osteogenesis through IL-4 signaling.\",\n      \"evidence\": \"Exosome-delivered A2M, shRNA IL-4 rescue, rat ONFH model\",\n      \"pmids\": [\"41203607\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"How A2M activates IL-4 signaling mechanistically unknown\", \"Single lab\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unresolved how A2M's extracellular conformational trap and LRP1 clearance mechanistically couple to the diverse intracellular signaling outcomes (NF-κB, PI3K/AKT, SMAD, RhoA, IL-4) attributed to it across tissues.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No unifying receptor/signaling model linking A2M binding to downstream pathway modulation\", \"Most signaling roles shown in single labs without reciprocal mechanistic validation\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 1, 2, 5, 8]},\n      {\"term_id\": \"GO:0140313\", \"supporting_discovery_ids\": [0, 1, 5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005576\", \"supporting_discovery_ids\": [4, 7]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1474244\", \"supporting_discovery_ids\": [5]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [3, 9]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [4, 5]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"LRP1\", \"IL1B\", \"TGFB1\", \"MMP2\", \"ALK\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":5,"faith_total":5,"faith_pct":100.0}}