Quarterly ReportJul 1 – Sep 30, 2025
Sepsis, Q3 2025 edition
We read 264 papers and selected 10.
Summary
The third quarter of 2025 marked a clear movement in sepsis research from nonspecific inflammation control toward biologically stratified, mechanism-directed intervention. Across the quarter, studies converged on immunometabolic regulation, pyroptosis and NETosis, endothelial–myeloid communication, gut–brain signaling, and immune-collapse mechanisms as actionable determinants of organ dysfunction and mortality. Diagnostic science also advanced through temporal-graph electronic health-record modeling, rapid molecular pathogen detection, host-response profiling, and biomarker-linked endotyping. Several papers connected circulating or tissue biomarkers to causal mechanisms and therapeutic rescue, strengthening the translational bridge from association to intervention. Most therapeutic findings remain preclinical, but the quarter generated multiple testable candidates for biomarker-enriched early-phase trials. Overall, the research landscape shifted toward precision sepsis in which disease phase, immune phenotype, organ-specific injury, and pathogen status jointly guide treatment.
Selected Articles
1. Homocysitaconate controls inflammation through reshaping methionine metabolism and N-homocysteinylation.
This study identifies homocysitaconate as an anti-inflammatory metabolite generated through interaction between homocysteine and itaconate biology. It binds methionyl-tRNA synthetase, reshapes methionine metabolism, suppresses N-homocysteinylation, promotes NLRP3 ubiquitination, and improves outcomes in sepsis models.
Impact: It reveals a previously unrecognized immunometabolic pathway connecting itaconate and homocysteine biology to inflammasome control, with therapeutic effects across inflammatory models.
Clinical Implications: The AHCY–MARS–methionine axis could support host-directed adjunctive therapy, but pharmacokinetics, safety, target engagement, and treatment timing require human evaluation.
Key Findings
- Homocysitaconate increases during inflammation and has anti-inflammatory activity.
- It binds MARS and suppresses N-homocysteinylation.
- It promotes NLRP3 ubiquitination and improves outcomes in sepsis models.
2. IGFBP6 orchestrates antiinfective immune collapse in murine sepsis via prohibitin-2-mediated immunosuppression.
IGFBP6 was associated with sepsis diagnosis and prognosis in multicenter human cohorts. It bound PHB2, impaired STAT1-driven CCL2 transcription and macrophage chemotaxis, suppressed Akt-dependent bactericidal activity, and was therapeutically rescued through PHB2–STAT1 or Akt pathways in septic mice.
Impact: It forms an unusually complete biomarker-to-mechanism-to-therapy chain for immune collapse and links human observations with causal in vivo rescue.
Clinical Implications: IGFBP6 could support prognostic stratification and selection for immunorestorative therapy, but treatment must be timed carefully to avoid aggravating uncontrolled inflammation.
Key Findings
- IGFBP6 was associated with diagnosis and prognosis across human cohorts.
- IGFBP6 impaired PHB2–STAT1–CCL2 signaling and macrophage chemotaxis.
- PHB2 or Akt rescue improved bacterial clearance and survival in mice.
3. Delaying pyroptosis with an AI-screened gasdermin D pore blocker mitigates inflammatory response.
The AI-screened peptide SK56 directly blocked gasdermin D pores without preventing upstream gasdermin D cleavage or IL-1β production. It reduced pyroptosis in human and murine cells, improved survival in endotoxemia and CLP models, and limited bystander immune activation in human alveolar organoids.
Impact: It demonstrates a first-in-class execution-stage strategy for modulating pyroptosis and connects AI-enabled discovery with a precise host-directed intervention.
Clinical Implications: GSDMD pore blockade may control inflammatory injury while preserving some upstream host-defense signaling, but pharmacokinetics, immunogenicity, pathogen clearance, and timing require extensive study.
Key Findings
- SK56 blocked GSDMD pores in macrophages and human leukocytes.
- SK56 improved survival in LPS and CLP sepsis models.
- It reduced bystander activation and cell death in human alveolar organoids.
4. Excessive HIF-1α driven by phospholipid metabolism causes septic cardiomyopathy through cytopathic hypoxia.
Inflammatory phospholipid signaling activates cardiomyocyte HIF-1α, suppresses mitochondrial respiration through iNOS-derived nitric oxide, and causes cytopathic hypoxia and contractile dysfunction. Genetic or pharmacologic inhibition of the pathway attenuated cardiac injury.
Impact: It provides a coherent molecular explanation for septic cardiomyopathy and identifies several pharmacologically approachable intervention points.
Clinical Implications: COX2, sPLA2, and HIF-1α pathway modulation warrants clinical translation with biomarkers of lipid signaling and cardiac mitochondrial dysfunction.
Key Findings
- HIF-1α suppressed mitochondrial respiration through iNOS-derived nitric oxide.
- Cardiac HIF-1α reduction attenuated cytopathic hypoxia and dysfunction.
- COX2 or sPLA2 inhibition reduced cardiac mitochondrial injury.
5. Small intestinal γδ T17 cells promote SAE through STING/C1q-induced microglial synaptic pruning in male mice.
This study shows that IL-7R-positive small-intestinal γδT17 cells migrate to the brain after sepsis and induce microglial synaptic pruning through STING/C1q signaling, producing sepsis-associated encephalopathy in male mice.
Impact: It establishes a specific peripheral-to-central immune circuit for neurological injury, expanding sepsis biology beyond conventional systemic inflammatory organ damage.
Clinical Implications: STING or C1q blockade may offer neuroprotective strategies, but sex-specific biology and confirmation in human encephalopathy are essential.
Key Findings
- Small-intestinal IL-7R-positive γδT17 cells migrated to the brain after sepsis.
- γδT17 cells induced microglial synaptic pruning through STING/C1q.
- The pathway caused sepsis-associated encephalopathy in male mice.
6. InfEHR: Clinical phenotype resolution through deep geometric learning on electronic health records.
InfEHR represents complete electronic health records as temporal graphs and uses deep geometric learning to infer clinical phenotypes with few labeled examples. Across two health systems, it substantially improved detection of culture-negative neonatal sepsis and postoperative acute kidney injury while retaining high specificity.
Impact: It addresses label scarcity, low-prevalence phenotype detection, and cross-system validation, representing a major methodological contribution to deployable precision-sepsis infrastructure.
Clinical Implications: Such systems could prioritize high-risk patients for review, but prospective studies must assess alert burden, calibration, equity, antibiotic exposure, and patient outcomes.
Key Findings
- Temporal-graph modeling enabled phenotype inference with minimal manual labeling.
- Sensitivity for culture-negative neonatal sepsis increased from 0.04 to 0.60 with high specificity.
- Performance exceeded physician heuristics across two health systems.
7. Ferroptosis mediated by the IDO1/Kyn/AhR pathway triggers acute thymic involution in sepsis.
IDO1 activity and kynurenine accumulation activated AhR and ferroptosis-related programs in thymocytes during sepsis. IDO1 inhibition restored thymic function and improved survival in septic mice, while pediatric samples showed elevated kynurenine/tryptophan ratios associated with thymic atrophy.
Impact: It connects a human-supported metabolic biomarker to immune-organ failure and demonstrates reversible therapeutic rescue in vivo.
Clinical Implications: Kynurenine/tryptophan ratios and ferroptosis signatures may support immune dysfunction stratification, but IDO1 inhibition must be tested carefully for effects on antimicrobial defense.
Key Findings
- Pediatric sepsis samples showed increased kynurenine/tryptophan ratios.
- IDO1-driven kynurenine activated AhR and ferroptosis programs in thymocytes.
- IDO1 inhibition restored thymic function and improved survival in mice.
8. Unraveling mitochondrial pyruvate dysfunction to mitigate hyperlactatemia and lethality in sepsis.
Sepsis-associated pyruvate dehydrogenase dysfunction was attributed to depletion of thiamine pyrophosphate rather than irreversible enzyme inactivation. Supplementation restored mitochondrial pyruvate oxidation, reduced lactate, enabled safer glucose administration, and improved survival in mice.
Impact: It identifies a measurable metabolic deficiency and a readily testable replacement strategy linking mechanism, phenotype, and survival benefit.
Clinical Implications: Functional thiamine status or pyruvate-oxidation markers could guide supplementation trials, but dose, timing, patient selection, and outcome effects require clinical testing.
Key Findings
- Sepsis impaired pyruvate oxidation through thiamine pyrophosphate depletion.
- Mitochondria compensated with glutamate-driven anaplerosis and alanine formation.
- Thiamine pyrophosphate supplementation reduced lactate and improved survival.
9. Src Reduces Neutrophil Extracellular Traps Generation and Resolves Acute Organ Damage.
Src activation drove NETosis in human and murine neutrophils through RAF/MEK/ERK signaling. Genetic deletion or pharmacologic inhibition reduced NET formation, reactive oxygen species, and acute organ injury in vivo, with human biomarker associations in sepsis and pancreatitis.
Impact: It defines a druggable kinase pathway controlling NETosis and links mechanistic inhibition to reduced organ injury with human biomarker relevance.
Clinical Implications: Src inhibition may be useful for NET-driven phenotypes, but immunosuppression, infection control, and selection of patients with active NETosis require careful evaluation.
Key Findings
- Src was activated during NETosis in human and murine sepsis.
- Src inhibition suppressed NET formation through RAF/MEK/ERK signaling.
- Genetic or pharmacologic inhibition reduced acute organ injury in vivo.
10. N-formyl methionine mediates NETosis of neutrophil to promote sepsis-induced cardiomyopathy via the FPR1 pathway.
Elevated serum N-formyl methionine was associated with sepsis-induced cardiomyopathy and activated FPR1/HIF-1α signaling, excessive NETosis, and cardiac injury. FPR1 deletion or inhibition reduced NET formation and inflammation while improving cardiac, mitochondrial, and survival outcomes in CLP mice.
Impact: It links a measurable circulating metabolite to a defined NET pathway and cardiac injury, creating a plausible biomarker-guided therapeutic strategy.
Clinical Implications: fMet and NET markers may identify patients at risk for septic cardiomyopathy, while selective FPR1 inhibition requires validation for efficacy, safety, and infection control.
Key Findings
- Serum fMet was elevated in patients with sepsis-induced cardiomyopathy.
- fMet and LPS activated FPR1/HIF-1α signaling and NET formation.
- FPR1 inhibition improved cardiac function, mitochondrial function, and survival in mice.