Modulation of Metabolomic Profile in Sepsis According to the State of Immune Activation.

OBJECTIVE: To investigate the metabolomic profiles associated with different immune activation states in sepsis patients. DESIGN: Subgroup analysis of the PROVIDE (a Personalized Randomized trial of Validation and restoration of Immune Dysfunction in severe infections and Sepsis) prospective clinical study. SETTING: Results of the PROVIDE study showed that patients with sepsis may be classified into three states of immune activation: 1) macrophage-activation-like syndrome (MALS) characterized by hyperinflammation, sepsis-induced immunoparalysis, and 3) unclassified or intermediate patients without severe immune dysregulation. PATIENTS OR SUBJECTS: Two hundred ten patients from 14 clinical sites in Greece meeting the Sepsis-3 definitions with lung infection, acute cholangitis, or primary bacteremia. INTERVENTIONS: During our comparison, we did not perform any intervention. MEASUREMENTS AND MAIN RESULTS: Untargeted metabolomics analysis was performed on plasma samples from 210 patients (a total of 1394 products). Differential abundance analysis identified 221 significantly different metabolites across the immune states. Metabolites were enriched in pathways related to ubiquinone biosynthesis, tyrosine metabolism, and tryptophan metabolism when comparing MALS to immunoparalysis and unclassified patients. When comparing MALS to unclassified, 312 significantly different metabolites were found, and pathway analysis indicated enrichment in multiple pathways. Comparing immunoparalysis to unclassified patients revealed only two differentially regulated metabolites. CONCLUSIONS: Findings suggest distinct metabolic dysregulation patterns associated with different immune dysfunctions in sepsis: the strongest metabolic dysregulation is associated with MALS.

THE ROLE OF OBESITY AND PLASMA ADIPOCYTOKINES IN IMMUNE DYSREGULATION IN SEPSIS PATIENTS.

Introduction: The dysregulated immune response in sepsis is highly variable, ranging from hyperinflammation to immunoparalysis. Obesity is associated with the release of inflammatory mediators from adipose tissue, known as adipocytokines, causing a chronic inflammatory state. Perhaps counterintuitively, obesity is also associated with lower mortality in sepsis patients. We investigated the association between obesity, circulating adipocytokine concentrations, immune dysregulation, and outcome in sepsis patients. Methods In this secondary analysis of a prospective study, plasma concentrations of the adipocytokines leptin, adiponectin, and resistin were assessed in 167 patients at diagnosis of sepsis due to pneumonia, bacteremia, or acute cholangitis. Adipocytokines were compared between patients with normal weight (body mass index [BMI], 18.5-24.9 kg/m 2 ; n = 67), overweight (BMI, 25.0-29.9 kg/m 2 ; n = 56), and obesity (BMI ≥30 kg/m 2 ; n = 42), as well as between immunological endotypes: hyperinflammation (n = 40), immunoparalysis (n = 62), and unclassified (n = 55). Results: Higher circulating concentrations of leptin were observed in patients with obesity compared with patients with normal weight ( P = 0.008) and overweight ( P = 0.02), whereas adiponectin and resistin plasma concentrations were not different ( P = 0.08 and P = 0.85, respectively). Resistin concentrations were associated with immunological endotypes, with the highest levels found in hyperinflammatory patients ( P < 0.001). Furthermore, resistin concentrations were predictive for 28-day mortality (adjusted odds ratio, 1.03 per 10 ng/mL; P = 0.04). These associations were not found for leptin and adiponectin. Conclusion: Obesity and BMI-related adipocytokines are not related to the development of a hyperactive or suppressed immune response as defined by ferritin and mHLA-DR expression in sepsis patients. Although resistin is related to the immune response and an increased risk of adverse clinical outcomes, these associations are similar in patients with normal weight, overweight, and obesity. This implies that the relationship between resistin and clinical outcome is likely driven by the inflammatory response and not by obesity itself. Taken together, although there exists a strong association between inflammation and sepsis mortality, our results do not point toward a role for obesity and BMI-related adipocytokines in immune dysregulation in sepsis patients.

Toward personalized immunotherapy in sepsis: The PROVIDE randomized clinical trial.

The state of immune activation may guide targeted immunotherapy in sepsis. In a double-blind, double-dummy randomized clinical study, 240 patients with sepsis due to lung infection, bacteremia, or acute cholangitis were subjected to measurements of serum ferritin and HLA-DR/CD14. Patients with macrophage activation-like syndrome (MALS) or immunoparalysis were randomized to treatment with anakinra or recombinant interferon-gamma or placebo. Twenty-eight-day mortality was the primary endpoint; sepsis immune classification was the secondary endpoint. Using ferritin >4,420 ng/mL and <5,000 HLA-DR receptors/monocytes as biomarkers, patients were classified into MALS (20.0%), immunoparalysis (42.9%), and intermediate (37.1%). Mortality was 79.1%, 66.9%, and 41.6%, respectively. Survival after 7 days with SOFA score decrease was achieved in 42.9% of patients of the immunotherapy arm and 10.0% of the placebo arm (p = 0.042). Three independent immune classification strata are recognized in sepsis. MALS and immunoparalysis are proposed as stratification for personalized adjuvant immunotherapy. Clinicaltrials.gov registration NCT03332225.