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Objectives: This study aims to investigate the diagnostic value of heparin-binding protein (HBP) in sepsis and develop a sepsis diagnostic model incorporating HBP with key biomarkers and disease-related scores for rapid, and accurate diagnosis of sepsis in the intensive care unit (ICU)., Design: Clinical retrospective cross-sectional study., Setting: A comprehensive teaching tertiary hospital in China., Participants: Adult patients (aged ≥18 years) who underwent HBP testing or whose blood samples were collected when admitted to the ICU., Main Outcome Measures: HBP, C reactive protein (CRP), procalcitonin (PCT), white blood cell count (WBC), interleukin-6 (IL-6), lactate (LAC), Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) score were recorded., Results: Between March 2019 and December 2021, 326 patients were enrolled in this study. The patients were categorised into a non-infection group (control group), infection group, sepsis group and septic shock group based on the final diagnosis. The HBP levels in the sepsis group and septic shock group were 45.7 and 69.0 ng/mL, respectively, which were significantly higher than those in the control group (18.0 ng/mL) and infection group (24.0 ng/mL) (p<0.001). The area under the curve (AUC) value of HBP for diagnosing sepsis was 0.733, which was lower than those corresponding to PCT, CRP and SOFA but higher than those of IL-6, LAC and APACHE II. Multivariate logistic regression analysis identified HBP, PCT, CRP, IL-6 and SOFA as valuable indicators for diagnosing sepsis. A sepsis diagnostic model was constructed based on these indicators, with an AUC of 0.901, a sensitivity of 79.7% and a specificity of 86.9%., Conclusions: HBP could serve as a biomarker for the diagnosis of sepsis in the ICU. Compared with single indicators, the sepsis diagnostic model constructed using HBP, PCT, CRP, IL-6 and SOFA further enhanced the diagnostic performance of sepsis., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To investigate the predictive value of left ventricular global longitudinal peak strain (GLPS) for the prognosis of septic patients., Methods: A prospective cohort study was conducted. Patients diagnosed with sepsis and admitted to the intensive care unit (ICU) of the First Affiliated Hospital, Sun Yat-sen University from December 2018 to November 2019 were enrolled. The patient characteristics, cardiac ultrasound parameters [left ventricular ejection fraction (LVEF), right ventricular ejection fraction (RVEF), four-dimensional ejection fraction (4DEF), GLPS] and cardiac biomarkers [N-terminal pro-brain natriuretic peptide (NT-proBNP), cardiac troponin T (cTnT)] within 24 hours of ICU admission, organ support therapies, severity of illness, and prognostic indicators were documented. The differences in clinical parameters between patients with varying outcomes during ICU hospitalization were assessed. Pearson correlation analysis was employed to explore the correlation between GLPS and other cardiac systolic parameters, as well as the associations between various cardiac systolic parameters and sequential organ failure assessment (SOFA) score. Receiver operator characteristic curve (ROC curve) was drawn to analyze the predictive capacity of cardiac ultrasound parameters and cardiac biomarkers for death during ICU hospitalization in septic patients., Results: A total of 50 septic patients were enrolled, with 40 surviving and 10 dying during ICU hospitalization, resulting in a mortality of 20.0%. All patients in the death group were male. Compared with the survival group, the patients in the death group were older, had a higher prevalence of diabetes mellitus, and received continuous renal replacement therapy (CRRT) more frequently, additionally, they exhibited more severe illness and had longer length of ICU stay. The levels of GLPS and cTnT in the death group were significantly elevated as compared with the survival group [GLPS: -7.1% (-8.5%, -7.0%) vs. -12.1% (-15.5%, -10.4%), cTnT (μg/L): 0.07 (0.05, 0.08) vs. 0.03 (0.02, 0.13), both P < 0.05]. However, no statistically significant difference was found in other cardiac ultrasound parameters or cardiac biomarkers between the two groups. Pearson correlation analysis revealed a negative correlation between GLPS and LVEF (r = -0.377, P = 0.014) and 4DEF (r = -0.697, P = 0.000), while no correlation was found with RVEF (r = -0.451, P = 0.069). GLPS demonstrated a positive correlation with SOFA score (r = 0.306, P = 0.033), while LVEF (r = 0.112, P = 0.481), RVEF (r = -0.134, P = 0.595), and 4DEF (r = -0.251, P = 0.259) showed no significant correlation with SOFA score. ROC curve analysis indicated that the area under the ROC curve (AUC) of GLPS for predicting death during ICU hospitalization in septic patients was higher than other cardiac systolic parameters, including LVEF, RVEF, and 4DEF, as well as cardiac biomarkers NT-proBNP and cTnT (0.737 vs. 0.628, 0.556, 0.659, 0.580 and 0.724). With an optimal cut-off value of -14.9% for GLPS, the sensitivity and negative predictive value reached to 100%., Conclusions: GLPS < -14.9% within 24 hours of ICU admission in septic patients indicated a reduced risk of death risk during ICU hospitalization, while also correlating with the severity of organ dysfunction in this patient population.

Abstract: Immunosuppression, commonly accompanied by persistent inflammation, is a key feature in the later phase of sepsis. However, the pathophysiological mechanisms underlying this phenomenon remain unclear. Dendritic cells (DCs), specifically tolerogenic DCs (tolDCs), play a crucial role in this process by regulating immune responses through inducing T cell anergy and releasing anti-inflammatory cytokines. Nevertheless, the existing cell models are inadequate for investigating tolDCs during the immunosuppressive phase of sepsis. Therefore, this study aimed to develop a novel in vitro model to generate tolDCs under chronic inflammatory conditions. We have successfully generated tolDCs by exposing them to sublethal lipopolysaccharide (LPS) for 72 h while preserving cell viability. Considering that IL-10-induced tolDCs (IL-10-tolDCs) are well-established models, we compared the immunological tolerance between LPS-tolDCs and IL-10-tolDCs. Our findings indicated that both LPS-tolDCs and IL-10-tolDCs exhibited reduced expression of maturation markers, whereas their levels of inhibitory markers were elevated. Furthermore, the immunoregulatory activities of LPS-tolDCs and IL-10-tolDCs were found to be comparable. These dysfunctions include impaired antigen presenting capacity and suppression of T cell activation, proliferation, and differentiation. Notably, compared with IL-10-tolDCs, LPS-tolDCs showed a reduced response in maturation and cytokine production upon stimulation, indicating their potential as a better model for research. Overall, in comparison with IL-10-tolDCs, our data suggest that the immunological dysfunctions shown in LPS-tolDCs could more effectively elucidate the increased susceptibility to secondary infections during sepsis. Consequently, LPS-tolDCs have emerged as promising therapeutic targets for ameliorating the immunosuppressed state in septic patients., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 by the Shock Society.)

Purpose: Aspirin is widely used in patients in the intensive care unit (ICU); nonetheless, its effects on these patients remain controversial. This retrospective analysis of data from clinical practice investigated the effects of aspirin on 28-day mortality in ICU patients., Methods: This retrospective study included data from patients in the Medical Information Mart for Intensive Care (MIMIC)-III database and the eICU-Collaborative Research Database (CRD). Patients aged 18 to 90 years and admitted to the ICU were eligible and were assigned to one of two groups according to whether they were given aspirin during their ICU stay. Multiple imputation was used for patients with >10% missing data. Multivariate Cox models and propensity score analysis were used to estimate the association of aspirin treatment with 28-day mortality among patients admitted to the ICU., Findings: In total, 146,191 patients were enrolled in this study, and 27,424 (18.8%) used aspirin. Aspirin treatment in ICU patients, especially in nonseptic patients, was associated with a lower 28-day all-cause mortality on multivariate Cox analysis (eICU-CRD, hazard ratio [HR] = 0.81, [95% CI, 0.75-0.87]; MIMIC-III, HR = 0.72 [95% CI, 0.68-0.76]). Aspirin treatment was associated with lower 28-day all-cause mortality after propensity score matching (eICU-CRD, HR = 0.80 [95% CI, 0.72-0.88]; MIMIC-III, HR = 0.80 [95% CI, 0.76-0.85]). However, on subgroup analysis, aspirin therapy was not associated with a lower 28-day mortality in patients without systemic inflammatory response syndrome (SIRS) symptoms or with sepsis in either database., Implications: Aspirin treatment during the ICU stay was associated with a significantly reduced 28-day all-cause mortality, particularly in patients with SIRS symptoms but without sepsis. In patients with sepsis and with/without SIRS symptoms, beneficial effects were not clear, or more careful patient selection is required., Competing Interests: Declaration of Interest This study was an analysis of data from a third-party anonymized publicly available database with preexisting institutional review board approval. The use of the MIMIC-III and eICU-CRD was approved by the CITI Program (record ID 35925919). The authors have indicated that they have no conflicts of interest with regard to the content of this article., (Copyright © 2023. Published by Elsevier Inc.)

Background: We evaluated the prognostic potential of the ratio of serum procalcitonin to monocytic HLA-DR for 28-day mortality in sepsis., Methods: In this retrospective study, a total of 91 patients with sepsis were enrolled. Clinical and laboratory data detected on admission (D0) and 7 days thereafter (D7) including the Acute Physiology and Chronic Health Evaluation II (APACHE II), the Sequential Organ Failure Assessment (admission SOFA), serum lactate, D-dimer, mHLA-DR, procalcitonin, platelet and white blood cell count, neutrophil-to-lymphocyte ratio were collected. The PCT/mHLA-DR ratio, the changes in mHLA-DR and WBC on day 7 compared with those on the day of admission and PCT clearance were calculated. Receiver operating characteristic curves, Kaplan-Meier survival curves, DeLong test and Cox regression analyses were used to assess and compare their predictive values., Results: Among all studied parameters, D 7 -PCT/mHLA-DR showed the best discriminatory property to differentiate survivors from non-survivors and was identified as an independent predictor of 28-day mortality., Conclusion: The D 7 -PCT/mHLA-DR ratio was more sensitive than either biomarker alone in predicting fatal outcome in septic patients. Combining pro-inflammatory and immunosuppression biomarkers might improve the prognostic accuracy in sepsis., (Copyright © 2021 Elsevier B.V. All rights reserved.)

This expert consensus uses clinical research evidence to explain the mechanism, monitoring and evaluation of sepsis-induced immunosuppression, and treatment with immune stimulation from two aspects: innate immunity and acquired immunity, aiming to help clinicians better understand sepsis-induced immune depression and its clinical significance. Clinical data suggest that the immune dysfunction is critically involved in the occurrence and development of sepsis. Quantitative detection of monocyte human leukocyte antigen DR and lymphocyte count can be used as important indicators to reflect the innate immune and acquired immune dysfunction in patients with sepsis. Immunomodulation therapy includes medication to improve innate immunity and acquired immunity, and immune stimulation combined with anti-inflammatory response.

The present study was to investigate the effect of mesenteric lymph duct drainage on lung inflammatory response, histological alteration, and endothelial cell apoptosis in septic rats. Animals were randomly assigned into four groups: control, sham surgery, sepsis, and sepsis plus mesenteric lymph drainage. We used the colon ascendens stent peritonitis (CASP) procedure to induce the septic model in rats, and mesenteric lymph drainage was performed with a polyethylene (PE) catheter inserted into mesenteric lymphatic. The animals were sacrificed at the end of CASP in 6 h. The mRNA expression levels of inflammatory mediators were measured by qPCR, and the histologic damage were evaluated by the pathological score method. It was found that mesenteric lymph drainage significantly reduced the expression of TNF- α , IL-1 β , and IL-6 mRNA in the lung. Pulmonary interstitial edema and infiltration of inflammatory cells were alleviated by mesenteric lymph drainage. Moreover, increased mRNA levels of TNF- α , IL-1 β , IL-6 mRNA, and apoptotic rate were observed in PMVECs treated with septic lymph. These results indicate that mesenteric lymph duct drainage significantly attenuated lung inflammatory injury by decreasing the expression of pivotal inflammatory mediators and inhibiting endothelial apoptosis to preserve the pulmonary barrier function in septic rats., Competing Interests: The authors declare that there are no conflicts of interest., (Copyright © 2020 Yongjun Liu et al.)

The use of tunneled dialysis catheters (TDCs) for patients in need of hemodialysis treatments (HDs) causes a significant number of bloodstream infections (BSIs), with very few viable preventative/treatment methods. Use of antibiotics is relatively ineffective due to the development of multidrug-resistant bacterial strains and the inability to penetrate bacterial biofilms. Nitric oxide (NO) is an endogenous gas molecule that has broad-spectrum antimicrobial/antibiofilm activity. In this study, the potential of creating a NO-releasing insert device that is attached onto the hub region cap of TDCs and locally releases NO within the TDC hub is evaluated for its antimicrobial/antibiofilm effectiveness. The NO-releasing insert contains the natural NO donor S -nitrosoglutathione (GSNO), along with zinc oxide (ZnO) nanoparticles to accelerate NO release from the GSNO, within a short silicone tube that is sealed at both ends and attached to the catheter cap. An in vitro 3-d-long antimicrobial study using catheter hubs yielded >6.6 log reductions of both Pseudomonas aeruginosa and Staphylococcus aureus for the NO-releasing insert device compared to controls. Two 14-d-long sheep studies demonstrated that the NO-releasing insert devices are exceptionally potent at preventing bacteria/biofilm growth on the inner lumen walls of TDCs compared to controls that have no preventative treatment devices as well as implanted TDCs that have commercially available chlorhexidine-treated insert devices placed within the hub regions.

Sepsis is a systemic inflammatory disease causing life-threatening multi-organ dysfunction. Accumulating evidences suggest that two forms of programmed necrosis, necroptosis and pyroptosis triggered by the pathogen component lipopolysaccharide (LPS) and inflammatory cytokines, play important roles in the development of bacterial sepsis-induced shock and tissue injury. Sepsis-induced shock and tissue injury required receptor-interacting protein kinase-3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL) phosphorylation, caspase11 activation and gasdermin D (GSDMD) cleavage. However, the synergistic effect of necroptosis and pyroptosis in the pathological progress of sepsis remains elusive. In this study, we found that blockage of both necroptosis and pyroptosis (double deletion of Ripk3/Gsdmd or Mlkl/Gsdmd) resulted in accumulative protection against septic shock, systemic blood clotting and multi-organ injury in mice. Bone marrow transplantation confirmed that necroptosis and pyroptosis in both myeloid and nonmyeloid cells are indispensable in the progression of sepsis-induced multi-organ injury. Both RIPK3 and GSDMD signaling collaborated to amplify necroinflammation and tissue factor release in macrophages and endothelial cells, which led to tissue injury. Furthermore, cell death induced by inflammatory cytokines and high-mobility group box 1 could be prevented by double ablation of Ripk3/Gsdmd or Mlkl/Gsdmd, suggesting that a positive feedback loop interconnecting RIPK3/MLKL and GSDMD machinery and inflammation facilitated sepsis progression. Collectively, our findings demonstrated that RIPK3-mediated necroptosis and GSDMD-mediated pyroptosis collaborated to amply inflammatory signaling and enhance tissue injury in the process of sepsis, which may shed new light on two potential targets of combined therapeutic interventions for this highly lethal disorder.

Objective: To investigate the relationship between plasma oxidative stress factors levels and organ damage parameters as well as prognosis in patients with sepsis., Methods: A case-control study was conducted. Twenty-five patients admitted to surgical intensive care unit (ICU) of the First Affiliated Hospital of Sun Yat-sen University from March to December in 2016 and diagnosed as sepsis were enrolled as study subjects. Another 15 patients without sepsis admitted to surgical ICU in the same period were enrolled as controls. General demographic data, main diagnoses, acute physiology and chronic health evaluation II (APACHE II) score within 24 hours, clinical laboratory indicators [alanine aminotransferase (ALT), aspartate transaminase (AST), serum creatinine (SCr), blood urea nitrogen (BUN), C-reactive protein (CRP), procalcitonin (PCT), white blood count (WBC)] and oxidative stress indicators [superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO)] as well as length of ICU stay, total hospital stay and 28-day mortality were recorded. Spearman or Pearson correlation method was used to analyze the correlation between oxidative stress indicators and organ damage indicators as well as prognosis in patients with sepsis. Receiver operator characteristic (ROC) curve was plotted to evaluate the predictive value of oxidative stress indicators for 28-day mortality in patients with sepsis., Results: The length of ICU stay in sepsis group was significantly longer than that in non-sepsis group [days: 7.0 (5.5, 11.0) vs. 4.0 (1.0, 11.0), P < 0.05], and AST, BUN, CRP, PCT, plasma MDA and NO levels were significantly higher than those in non-sepsis group [AST (U/L): 50.76±19.53 vs. 28.53±14.02, BUN (mmol/L): 9.99±5.26 vs. 6.97±4.32, CRP (mg/L): 109.28±42.79 vs. 60.33±46.68, PCT (μg/L): 5.4 (0.3, 24.0) vs. 0.6 (0.1, 1.5), MDA (ng/L): 488.31±76.68 vs. 399.30±50.23, NO (ng/L): 5.08±0.89 vs. 4.42±0.88, all P < 0.05]. There was no significant difference in gender, age, APACHE II score, total hospital stay, 28-day mortality, ALT, SCr, WBC or plasma SOD activity between the two groups. The correlation analysis between oxidative stress parameters and organ damage parameters as well as prognosis in patients with sepsis showed that MDA and NO were positively correlated with SCr (r value was 0.426 and 0.431, respectively, both P < 0.05), and there was a positive correlation between MDA and NO (r = 0.990, P < 0.01); plasma SOD activity was negatively correlated with 28-day mortality (r = -0.468, P < 0.05), while MDA and NO levels were positively correlated with 28-day mortality (r value was 0.598 and 0.611, respectively, both P < 0.01). ROC curve analysis showed that plasma SOD, MDA and NO levels had a good independent predictive effect on 28-day mortality, the area under ROC curve (AUC) was 0.816±0.087, 0.904±0.078 and 0.912±0.071, and the best cut-off value was 40.76% (sensitivity 68.4%, specificity 100%), 487.93 ng/L (sensitivity 83.3%, specificity 89.5%) and 5.31 ng/L (sensitivity 83.3%, specificity 89.5%), respectively., Conclusions: The plasma levels of oxidative stress factors in patients with sepsis are significantly increased, which is closely related to organ damage and poor prognosis. The plasma SOD, MDA and NO levels can be used as independent bio-marker to predict the 28-day mortality of patients with sepsis.

Objectives: To examine the effects and mechanisms of human neutrophil peptides in systemic infection and noninfectious inflammatory lung injury., Design: Prospective experimental study., Setting: University hospital-based research laboratory., Subjects: In vitro human cells and in vivo mouse models., Interventions: Wild-type (Friend virus B-type) and conditional leukocyte human neutrophil peptides transgenic mice were subjected to either sepsis induced by cecal ligation and puncture or acute lung injury by intratracheal instillation of hydrochloric acid followed by mechanical ventilation. Using human neutrophil peptides as bait, the basal cell adhesion molecule (CD239) and the purinergic P2Y purinoceptor 6 receptor were identified as the putative human neutrophil peptides receptor complex in human lung epithelial cells., Measurements and Main Results: In the cecal ligation and puncture sepsis model, Friend virus B-type mice exhibited higher systemic bacterial load, cytokine production, and lung injury than human neutrophil peptides transgenic mice. Conversely, an increased lung cytokine production was seen in Friend virus B-type mice, which was further enhanced in human neutrophil peptides transgenic mice in response to two-hit lung injury induced by hydrochloric acid and mechanical ventilation. The human neutrophil peptides-mediated inflammatory response was mediated through the basal cell adhesion molecule-P2Y purinoceptor 6 receptor signal pathway in human lung epithelial cells., Conclusions: Human neutrophil peptides are critical in host defense against infectious sepsis by their cationic antimicrobial properties but may exacerbate tissue injury when neutrophil-mediated inflammatory responses are excessive in noninfectious lung injury. Targeting the basal cell adhesion molecule/P2Y purinoceptor 6 signaling pathway may serve as a novel approach to attenuate the neutrophil-mediated inflammatory responses and injury while maintaining the antimicrobial function of human neutrophil peptides in critical illness.

Introduction: Sepsis is a life-threatening organ dysfunction caused by host immune response to infection. In this regard, modifying host immune response may help to eliminate systemic infection and restore organ function. Thymosin alpha 1 (Tα1), acting as an immune modulator, exerts great biological influence in activating and restoring the dysregulated immune response for patients with sepsis., Areas Covered: In this review, we summarize the clinical studies of Tα1 treatment alone and in combination with anti-inflammatory for patients with sepsis or septic shock. Clinical studies were collected from available English and Chinese databases., Expert Opinion: In previous studies, single or combined treatment with Tα1 reduced the mortality rate of sepsis, improved the expression of HLA-DR on monocyte, and diminished the incidence of secondary infection. Based on the existing studies, Tα1 seems to be a promising alternative adjuvant therapy for sepsis. However, sepsis is a remarkably heterogeneous clinical syndrome, so much so that it is impossible to generalize the clinical results to all septic patients. Also, the present studies on Tα1 treatment are not able to focus on the immunosuppressive individuals. We believe that selecting septic patients with immunosuppression will be more likely to reveal the efficacy of Tα1 in future trials.

Introduction: Severe sepsis is associated with a high mortality rate despite implementation of guideline recommendations. Adjunctive treatment may be efficient and require further investigation. In light of the crucial role of immunologic derangement in severe sepsis, thymosin alpha 1 (Tα1) is considered as a promising beneficial immunomodulatory drug. The trial is to evaluate whether Tα1 improves 28-day all-cause mortality rates and immunofunction in patients with severe sepsis., Methods: We performed a multicenter randomized controlled trial in six tertiary, teaching hospitals in China between May 12, 2008 and Dec 22, 2010. Eligible patients admitted in ICU with severe sepsis were randomly allocated by a central randomization center to the control group or Tα1 group (1:1 ratio). The primary outcome was death from any cause and was assessed 28 days after enrollment. Secondary outcomes included dynamic changes of Sequential Organ Failure Assessment (SOFA) and monocyte human leukocyte antigen-DR (mHLA-DR) on day 0, 3, 7 in both groups. All analyses were done on an intention-to-treat basis., Results: A total of 361 patients were allocated to either the control group (n = 180) or Tα1 (n = 181) group. The mortalities from any cause within 28 days in the Tα1 group and control group were 26.0% and 35.0% respectively with a marginal P value (nonstratified analysis, P = 0.062; log rank, P = 0.049); the relative risk of death in the Tα1 group as compared to the control group was 0.74 (95% CI 0.54 to 1.02). Greater improvement of mHLA-DR was observed in the Tα1 group on day 3 (mean difference in mHLA-DR changes between the two groups was 3.9%, 95% CI 0.2 to 7.6%, P = 0.037) and day 7 (mean difference in mHLA-DR changes between the two groups was 5.8%, 95% CI 1.0 to 10.5%, P = 0.017) than in the control group. No serious drug-related adverse event was recorded., Conclusions: The use of Tα1 therapy in combination with conventional medical therapies may be effective in improving clinical outcomes in a targeted population of severe sepsis., Trial Registration: ClinicalTrials.gov NCT00711620.

• Septic shock is a subtype of sepsis with a high mortality rate. • Septic shock patients' mortality can be reduced by early prediction and interventions. • We develop a model to predict septic shock patients' mortality based on clinical data. • The model has high prediction accuracy and can be used to assist clinical diagnosis. • This is the first research to predict septic shock patient's mortality via clinic available data. Septic shock has become the leading cause of morbidity and mortality in the ICU. The survival rate of septic shock patients can be improved if their mortality can be predicted in advance to take interventions early. However, currently there is no model to predict the mortality of septic shock patients. We aim to develop such a model. We selected septic shock patients from MIMIC-IV according to Sepsis-3. From vital signs and clinical examination data, we extracted 46 features including markers of inflammation, organ dysfunction or injury. Using these features, we developed a model named ShockSurv basing on the XGBoost Algorithm to predict 28-day mortality for septic shock patients. We also compared the model with five machine learning methods and three clinical critical scoring systems and conduct external independent validation on a multi-center database. 11,947 septic shock patients were enrolled in the training and independent test cohort, with a 28-day mortality of 19.03%. Our model achieves AUROC of 0.9161 (95% CI: 0.8703–0.9390) by the 5-fold cross-validation in the training cohort and 0.9027 (95% CI: 0.8802–0.9253) in the independent test cohort, which are superior to the comparative models. The top 15 important variables identified by our model are consistent with clinically observed variables important for patient outcomes. The proposed model can accurately predict 28-day mortality for septic shock patients. Based on the prediction, clinicians can take appropriate clinical intervention timely for more critical patients to reduce their mortality. [ABSTRACT FROM AUTHOR]

Following long‑term exposure to endotoxins, macrophages enter an immunosuppressive state that renders them unable respond to subsequent exposures to endotoxin, a phenomenon that is termed ʻendotoxin toleranceʼ. Endotoxin tolerance increases the risks of secondary infection and mortality in patients with sepsis. In endotoxin‑tolerant macrophages, the mixed variation of gene transcription is referred to as macrophage reprogramming. The mechanisms underlying macrophage reprogramming remain unclear at present. Interferon‑induced double‑stranded RNA‑dependent protein kinase (PKR) is a widely expressed serine/threonine protein kinase. In addition to antiviral effects, PKR regulates the transcription of inflammatory cytokines by affecting transcription factors. However, the role of PKR in macrophage reprogramming remains to be elucidated. In the present study, the expression of inflammatory cytokines differed in lipopolysaccharide (LPS)‑tolerant RAW264.7 macrophages compared with LPS‑activated macrophages. Specifically, reverse transcription‑quantitative polymerase chain reaction results demonstrated that the mRNA levels of tumor necrosis factor‑α, interleukin‑1β (IL‑1β), C‑X‑C motif chemokine ligand 11, C‑C motif chemokine ligand (CCL17), CCL22 and suppressor of cytokine signaling 3 were decreased, and mRNAs levels of arginase‑1 (Arg1) and nitric oxide synthase 2 (iNOS) were increased, in LPS‑tolerant macrophages compared with LPS‑activated macrophages. Furthermore, western blot analysis demonstrated that the protein levels of phosphorylated (p)‑PKR were significantly decreased in the LPS‑tolerant cells. PKR activation with rotenone (10 μM) abrogated endotoxin tolerance by increasing the levels of the IL‑1β, CCL17 and CCL22 mRNAs and decreasing the levels of the Arg1 and iNOS mRNAs. Furthermore, western blotting demonstrated that AKT was markedly inactivated in endotoxin‑tolerant cells, as indicated by reduced p‑AKT levels. However, levels of p‑AKT were markedly increased following rotenone‑induced PKR activation in endotoxin‑tolerant cells. Ly294002 (10 μM), a phosphatidylinositol‑4,5‑bisphosphate 3‑kinase (PI3K)/AKT signaling inhibitor, partially reversed the rotenone‑induced alleviation of endotoxin tolerance. These results demonstrated that PKR inhibition mediated endotoxin tolerance in macrophages, and these effects were partially mediated by PI3K/AKT signaling. PKR may be a potential target for the treatment of endotoxin tolerance in patients with sepsis. [ABSTRACT FROM AUTHOR]

Apoptosis of alveolar macrophages (AMs) plays a pathogenic role in acute lung injury (ALI) and its severe type, acute respiratory distress syndrome (ARDS). Mesenchymal stem cells (MSCs) are promising therapeutic cells for preventing apoptosis and eliminating cellular injury. We investigated the effects of rat bone marrow mesenchymal stem cells (BMSCs) on lipopolysaccharide (LPS)-induced apoptosis in AMs using transwell experiments, and examined the underlying mechanisms LPS induced AMs apoptosis in a dose- and time-dependent fashion, whereas BMSCs reduced AMs apoptosis when co-cultured at appropriate ratios. BMSCs decreased expression of cleaved caspase-3 and the pro-apoptotic protein, Bax, whilst increased levels of the anti-apoptotic protein, Bcl-2, prolonging the lifespan of AMs in vitro. Promotion of AMs survival by BMSCs required down-regulation of p-GSK-3β and β-catenin in AMs. The anti-apoptosis action of BMSCs was reversed by SB216763, a specific inhibitor of GSK-3β that also activates Wnt/β-catenin signaling. In conclusion, BMSCs can attenuate AM apoptosis partially by suppressing the Wnt/β-catenin pathway. [ABSTRACT FROM AUTHOR]

Excessive activation of the coagulation system leads to life-threatening disseminated intravascular coagulation (DIC). Here, we examined the mechanisms underlying the activation of coagulation by lipopolysaccharide (LPS), the major cell-wall component of Gram-negative bacteria. We found that caspase-11, a cytosolic LPS receptor, activated the coagulation cascade. Caspase-11 enhanced the activation of tissue factor (TF), an initiator of coagulation, through triggering the formation of gasdermin D (GSDMD) pores and subsequent phosphatidylserine exposure, in a manner independent of cell death. GSDMD pores mediated calcium influx, which induced phosphatidylserine exposure through transmembrane protein 16F, a calcium-dependent phospholipid scramblase. Deletion of Casp11 , ablation of Gsdmd , or neutralization of phosphatidylserine or TF prevented LPS-induced DIC. In septic patients, plasma concentrations of interleukin (IL)-1α and IL-1β, biomarkers of GSDMD activation, correlated with phosphatidylserine exposure in peripheral leukocytes and DIC scores. Our findings mechanistically link immune recognition of LPS to coagulation, with implications for the treatment of DIC. • Deletion of caspase-11 prevents disseminated intravascular coagulation (DIC) in sepsis • Deletion of GSDMD prevents caspase-11- and TF-mediated DIC in endotoxemia • GSDMD deficiency inhibits endotoxin-induced TF activation by reducing PS exposure • Activation of GSDMD by caspase-11 triggers Ca2+-dependent PS exposure through TMEM16F Excessive activation of the coagulation system by endotoxin leads to life-threatening disseminated intravascular coagulation (DIC). Yang, Cheng et al. reveal that caspase-11, a cytosolic LPS receptor, activates the coagulation cascade by enhancing the activation of tissue factor, an initiator of coagulation, through triggering the formation of gasdermin (GASMD) pores and subsequent phosphatidylserine exposure, in a manner independent of cell death. [ABSTRACT FROM AUTHOR]