Monthly ReportDec 1–31, 2025
Sepsis, December 2025 edition
We read 365 papers and selected 5.
Summary
December sepsis research increasingly treated sepsis as a dynamic, anatomically heterogeneous syndrome requiring longitudinal molecular profiling and phenotype-specific intervention. Major mechanistic themes included mitochondrial dysfunction, endothelial injury, ferroptosis, PANoptosis, immunothrombosis, cardiac endothelial senescence, and organ-specific immune reprogramming. Translational research expanded from biomarker discovery toward targeted strategies, including Notch1-DLL4 blockade, IFNβ-informed DIC risk stratification, STING or heme-directed therapy, and immune-phenotype-guided treatment. Clinically, the strongest practice-facing evidence supported selective anticoagulation, structured antibiotic de-escalation, and cautious use of phenotype-guided immunotherapy, while many innovative therapies remain preclinical.
Selected Articles
1. Single-cell multi-omic landscape reveals anatomical-specific immune features in adult and pediatric sepsis.
In 281 adults and children with sepsis and controls, integrated single-cell transcriptomics, T-cell and B-cell receptor sequencing, CITE-seq, bulk RNA sequencing, and plasma proteomics showed that the anatomical source of infection imprints distinct immune programs. The study identified shared core features across ages as well as source- and age-specific states, including an NR4A2-associated signature, providing a reference map for precision sepsis stratification.
Impact: This large, deeply phenotyped human study reframes sepsis heterogeneity around infection source and age rather than treating sepsis as a uniform systemic syndrome. Its integrated molecular reference map can support biomarker development, trial enrichment, and source-specific immunomodulation.
Clinical Implications: Future diagnostic pathways and clinical trials should account for infection source and age when interpreting immune biomarkers. Source-specific immune signatures may improve prognosis and identify candidates for targeted immunomodulation, although prospective clinical utility and assay standardization remain necessary.
Key Findings
- Integrated multi-omics in 281 individuals identified infection-site-specific immune programs across adult and pediatric sepsis.
- Adult and pediatric sepsis shared core immune features but also showed distinct source- and age-related states.
- An NR4A2-associated signature emerged as a candidate marker of sepsis immune heterogeneity.
2. Longitudinal multi-omic signatures of ARDS and sepsis inflammatory phenotypes identify pathways associated with mortality.
Longitudinal metabolomic and transcriptomic profiling of 160 ARDS patients identified four mortality-associated molecular signatures linked to innate immune activation, glycolysis, hepatic and immune dysfunction, impaired fatty acid oxidation, interferon suppression, redox impairment, and mitochondrial dysfunction. The signatures persisted through day 2 and were validated in an independent critically ill sepsis cohort, supporting a mechanistic framework for endotype-guided therapy.
Impact: The study moves beyond static inflammatory phenotypes by identifying persistent, externally validated molecular pathways associated with mortality. Its convergence on mitochondrial and metabolic dysfunction provides a coherent basis for longitudinal endotype-guided intervention.
Clinical Implications: Repeated molecular profiling may help determine whether mitochondrial, fatty-acid oxidation, interferon, redox, or immune pathways are active at a given time. These signatures could support endotype-enriched trials, but causal validation, assay simplification, and prospective treatment studies are still needed.
Key Findings
- Four mortality-associated molecular signatures were identified across inflammatory phenotypes.
- All signatures converged on or included mitochondrial dysfunction-related biology and persisted from day 0 to day 2.
- The molecular signatures were externally validated in an independent critically ill sepsis cohort.
3. DLL4+ neutrophils promote Notch1-mediated endothelial PANoptosis to exacerbate acute lung injury in sepsis.
This mechanistic study identified an eCIRP-induced DLL4-positive neutrophil subset that activates Notch1 on pulmonary vascular endothelial cells, triggering ZBP1-mediated endothelial PANoptosis and worsening sepsis-induced acute lung injury. A rationally designed Notch1-DLL4 inhibitor reduced PANoptosis, vascular permeability, lung injury, inflammatory markers, and mortality in sepsis models.
Impact: The study defines a previously unrecognized neutrophil-endothelial pathway and links it to a target-specific inhibitor with functional and survival benefit in vivo. It provides a strong mechanistic basis for endothelial-protective therapy in sepsis-associated acute lung injury.
Clinical Implications: Notch1-DLL4 blockade could become an adjunctive therapy for sepsis-associated acute lung injury, but human biomarker validation, pharmacokinetic studies, infection-risk assessment, and safety testing are required before clinical translation.
Key Findings
- eCIRP induced DLL4-positive neutrophils that drove ZBP1-initiated endothelial PANoptosis.
- DLL4 binding to endothelial Notch1 amplified PANoptosis and vascular barrier failure.
- A Notch1-derived inhibitor reduced lung injury and inflammation and improved survival in sepsis models.
4. A Critical Role for MALAT1 in Gram-negative Bacteria-induced Coagulation via Regulation of Caspase-11 signaling.
Admission plasma IFNβ predicted the development of septic DIC within 48 hours, whereas HMGB1 did not. Mechanistic studies showed that IFNβ induces macrophage MALAT1, which suppresses GPX4 activity and promotes LPS internalization, caspase-11 activation, GSDMD-dependent phosphatidylserine exposure, and immunocoagulation.
Impact: This paper bridges a clinically measurable early biomarker with a detailed immunocoagulation mechanism. It therefore offers both a potential early DIC prediction strategy and a mechanistically defined MALAT1-GPX4-caspase-11 therapeutic axis.
Clinical Implications: IFNβ may help identify patients at high risk for early DIC, while MALAT1, GPX4, or caspase-11 modulation could become future therapeutic approaches. External clinical validation and careful assessment of infection-control and bleeding consequences are essential.
Key Findings
- Admission IFNβ, but not HMGB1, correlated with DIC onset 48 hours later.
- IFNβ induced macrophage MALAT1, reduced GPX4 activity, and enhanced caspase-11-dependent coagulation.
- Macrophage-specific Malat1 deletion reduced phosphatidylserine exposure and protected against bacteria-induced coagulation.
5. Heme drives cardiac endothelial senescence in sepsis via STING activation.
This study identified cardiac endothelial cells as the predominant senescent population in septic hearts and showed that elevated heme directly activates STING, promoting endothelial senescence and cardiac dysfunction. Pharmacologic STING inhibition and hemopexin-mediated heme clearance reduced senescence and improved cardiac recovery in septic mice.
Impact: The study establishes a novel hemolysis-to-STING-to-endothelial-senescence pathway linking circulating heme to septic cardiomyopathy. It also identifies two intervention points, heme clearance and STING inhibition, with in vivo functional benefit.
Clinical Implications: Hemopexin-based heme scavenging or STING inhibition could eventually be evaluated for septic cardiac dysfunction, but human confirmation, patient selection, dosing, immunologic safety, and interaction with infection control require substantial further study.
Key Findings
- Cardiac endothelial cells were the predominant senescent population in septic cardiac tissue.
- Heme promoted STING polymerization and activation, driving endothelial senescence and cardiac dysfunction.
- STING inhibition or hemopexin-mediated heme clearance improved cardiac recovery in septic mice.