Daily Sepsis Research Analysis
Three studies advance sepsis research across diagnostics and therapeutics: an international prospective cohort validates a rapid gene-expression panel to identify high-risk sepsis endotypes; a multicentre study defines an exosome-derived three-miRNA signature that distinguishes septic from non-septic shock with high accuracy; and a preclinical study demonstrates noninvasive vagus nerve stimulation via ultrasound-activated gastric piezoelectric particles that reduces inflammation and improves sur
Summary
Three studies advance sepsis research across diagnostics and therapeutics: an international prospective cohort validates a rapid gene-expression panel to identify high-risk sepsis endotypes; a multicentre study defines an exosome-derived three-miRNA signature that distinguishes septic from non-septic shock with high accuracy; and a preclinical study demonstrates noninvasive vagus nerve stimulation via ultrasound-activated gastric piezoelectric particles that reduces inflammation and improves survival in murine sepsis.
Research Themes
- Precision endotyping and prognostic stratification in sepsis using rapid transcriptomics
- Extracellular vesicle miRNA biomarkers for septic shock discrimination
- Bioelectronic and neuromodulatory therapies for immune control in sepsis
Selected Articles
1. Noninvasive Vagus Nerve Electrical Stimulation for Immune Modulation in Sepsis Therapy.
In a murine sepsis model, ingestible piezoelectric particles activated by low-intensity ultrasound stimulated vagal afferents, engaging the cholinergic anti-inflammatory pathway. This neuromodulatory approach reduced systemic inflammation, mitigated organ injury and weight loss, and improved survival, suggesting a feasible, noninvasive bioelectronic therapy for sepsis.
Impact: Introduces a novel, noninvasive neuromodulatory therapy that improves survival in sepsis, bridging materials science and immunology. If translatable, it could redefine sepsis management beyond pharmacotherapy.
Clinical Implications: Not yet ready for clinical use, but points to bioelectronic vagal modulation as an adjunctive strategy for sepsis. Encourages early-phase safety and feasibility trials of ultrasound-driven neuromodulation.
Key Findings
- Ultrasound-activated piezoelectric gastric particles stimulated vagal afferents via TRPV1 targeting.
- Neuromodulation reduced systemic inflammation, tissue injury, and weight loss in murine sepsis.
- Intervention improved survival by modulating splenic immune cell responses through the CAIP.
- Approach is noninvasive and compatible with portable ultrasound with minimal thermal effects.
Methodological Strengths
- In vivo demonstration of efficacy with survival outcomes in a rigorous murine sepsis model
- Mechanistic linkage to the cholinergic anti-inflammatory pathway and vagal afferent activation
Limitations
- Preclinical mouse data without human validation; safety, dosing, and biodistribution of particles remain unknown
- Comparative effectiveness versus standard sepsis therapies and long-term outcomes were not assessed
Future Directions: Conduct GLP toxicology, biodistribution, and dose-optimization studies, followed by first-in-human feasibility trials of ultrasound-driven vagal neuromodulation in sepsis or endotoxemia.
Sepsis presents a significant medical challenge due to its intense inflammatory response to infection, often resulting in high mortality rates. A promising therapeutic strategy targets the cholinergic anti-inflammatory pathway (CAIP), which regulates immune responses. This study investigates the ingestion of piezoelectric particles that adhere to the stomach lining, specifically targeting TRPV1 receptors. In a mouse model of sepsis, these particles, when activated by low-intensity pulsed ultrasound, generate mild electrical pulses. These pulses stimulate vagal afferent fibers, transmitting signals to the brain and modulating the neural-immune network via the CAIP. Consequently, this leads to a reduction in systemic inflammation, mitigating weight loss, alleviating multiple tissue injuries, and preventing death by modulating immune cells in the spleen. This approach addresses the critical need for noninvasive sepsis therapies, potentially improving patient outcomes. Utilizing portable ultrasound equipment with minimal thermal effects, this technique offers a safe and convenient treatment option, even for home use.
2. An international observational study validating gene-expression sepsis immune subgroups.
Across 17 ICUs and 357 adults with sepsis, a rapid multiplex RNA panel (FilmArray prototype) assigned patients to high vs low risk groups, with high-risk classification consistently associated with higher 90-day mortality, especially at day 6–8. Serial endotyping decreased the proportion of high-risk patients over time.
Impact: Provides multicountry prospective validation that rapid transcriptomic profiling can stratify sepsis mortality risk, enabling precision medicine trial enrichment and potential bedside triage.
Clinical Implications: Supports integrating rapid gene-expression panels for prognostic stratification to select patients for targeted interventions or trials and to inform intensity of monitoring.
Key Findings
- In 357 ICU sepsis patients, high-risk assignment by model 1 was associated with higher 90-day mortality at all timepoints (S1, S2, S3).
- Model 2 showed a significant mortality difference at day 6–8 (S2: 34% vs 14%, p=0.002).
- The proportion of high-risk patients declined over time, indicating dynamic immune trajectories captured by the panel.
Methodological Strengths
- Prospective, multicentre international cohort with centralized assay processing
- Predefined models applied on a rapid multiplex platform with clinically relevant 90-day outcomes
Limitations
- Observational design without interventional testing of stratified care
- Generalizability beyond European ICUs and optimal timing of sampling require further study
Future Directions: Use the panel for prospective enrichment in adaptive trials testing immunomodulators; evaluate integration into bedside workflows and cost-effectiveness.
BACKGROUND: Sepsis gene-expression sub-phenotypes with prognostic and theranostic potential have been discovered. These have been identified retrospectively and have not been translated to methods that could be deployed at the bedside. We aimed to identify subgroups of septic patients at high-risk of poor outcome, using a rapid, multiplex RNA-based test. METHODS: Adults with sepsis, in the intensive care unit (ICU) were recruited from 17 sites in the United Kingdom, Sweden and France. Blood was collected at days 2-5 (S1), 6-8 (S2) and 13-15 (S3) after ICU admission and analyzed centrally. Patients were assigned into 'high' and 'low' risk groups using two models previously developed for the Immune-Profiling Panel prototype on the bioMérieux FilmArray® system. RESULTS: 357 patients were recruited (March 2021-November 2022). 69% were male with a median age of 67 years, APACHE II score of 21 and a 30% 90-day mortality rate. The proportions of high-risk patients decreased over the three sampling times (model 1: 53%, 40%, 15% and model 2: 81%, 74%, 37%). In model 1, 90-day mortality was higher in a high-risk group at each time (S1: 35% vs 24%, p = 0.04; S2: 43% vs 20%, p < 0.001; S3: 52% vs 24%, p = 0.007). In model 2, mortality was only significantly different at the second sampling time (S1: 30% vs 27%, p = 0.77; S2: 34% vs 14%, p = 0.002; S3: 35% vs 23%, p = 0.13). CONCLUSIONS: Gene-expression diagnostics can identify patients with sepsis at high-risk of poor outcomes and could be used to identify patients for precision medicine trials. REGISTRATION: ISRCTN11364482 Registered 24th September 2020.
3. Study on the diagnostic role of exosome-derived miRNAs in postoperative septic shock and non-septic shock patients.
In postsurgical shock, a multicentre prospective study identified and validated a three-miRNA exosomal signature (miR-100-5p, miR-148a-3p, miR-451a) that discriminates septic from non-septic shock with AUC 0.894 in discovery and 0.960 by qPCR in validation.
Impact: Provides a minimally invasive, biologically plausible biomarker set with strong discrimination to guide early differentiation of septic shock, informing timely antibiotics and stewardship.
Clinical Implications: A validated three-miRNA signature could be integrated into early postoperative shock workflows to distinguish septic vs non-septic shock and tailor resuscitation and antimicrobial strategies.
Key Findings
- Thirty exosome-derived miRNAs differed between septic and non-septic shock in a discovery cohort of 109 patients.
- A three-miRNA panel (miR-100-5p, miR-148a-3p, miR-451a) achieved AUC 0.894 in discovery and 0.960 by qPCR validation in 52 patients.
- Sampling within 24 hours of shock diagnosis supports early diagnostic applicability.
Methodological Strengths
- Multicentre prospective design with independent validation cohort
- Orthogonal validation via qPCR ensures translational feasibility
Limitations
- Modest sample size and focus on postsurgical ICU patients may limit generalizability
- Clinical utility and turnaround time in routine practice remain to be established
Future Directions: Prospectively test the three-miRNA panel in broader sepsis populations and evaluate clinical decision impact, cost-effectiveness, and integration with existing sepsis bundles.
BACKGROUND: Diagnosing septic shock promptly is essential but challenging, especially due to its clinical similarity to non-septic shock. Extracellular vesicle-derived miRNAs may serve as biomarkers to distinguish septic shock from non-septic shock, providing a more accurate diagnostic tool for postsurgical patients. This study aims to identify extracellular vesicle-derived miRNA signatures that differentiate septic shock from non-septic shock in postsurgical patients, potentially improving diagnostic accuracy and clinical decision-making. METHODS: A multicentre, prospective study was conducted on miRNA profiles in shock patients. Two cohorts were recruited from the Intensive Care Units of two Spanish hospitals: a discovery cohort with 109 patients and a validation cohort with 52 patients. Plasma samples were collected within 24 h of shock diagnosis and subjected to miRNA sequencing. High-throughput sequencing data from the discovery cohort were analysed to identify differentially expressed miRNAs. These findings were validated via qPCR in the validation cohort. RESULTS: Thirty miRNAs were identified as significantly differentially expressed between septic and non-septic shock patients. Among these, six miRNAs-miR-100-5p, miR-484, miR-10a-5p, miR-148a-3p, miR-342-3p, and miR-451a-demonstrated strong diagnostic capabilities for septic shock. A combination of miR-100-5p, miR-148a-3p, and miR-451a achieved an area under the curve of 0.894, with qPCR validation in the validation cohort yielding an area under the curve of 0.960. CONCLUSIONS: This study highlights extracellular vesicle-derived miRNAs as promising biomarkers for differentiating septic from non-septic shock. The identified three-miRNA signature has significant potential to enhance septic shock diagnosis, thereby aiding in timely and appropriate treatment for postsurgical patients.