Pharmacologically significant constituents collectively responsible for anti-sepsis action of XueBiJing, a Chinese herb-based intravenous formulation

Sepsis, a life-threatening health issue, lacks effective medicine targeting the septic response. In China, treatment combining the intravenous herbal medicine XueBiJing with conventional procedures reduces the 28-day mortality of critically ill patients by modulating septic response. In this study, we identified the combined active constituents that are responsible for the XueBiJing's anti-sepsis action. Sepsis was induced in rats by cecal ligation and puncture (CLP). The compounds were identified based on their systemic exposure levels and anti-sepsis activities in CLP rats that were given an intravenous bolus dose of XueBiJing. Furthermore, the identified compounds in combination were assessed, by comparing with XueBiJing, for levels of primary therapeutic outcome, pharmacokinetic equivalence, and pharmacokinetic compatibility. We showed that a total of 12 XueBiJing compounds, unchanged or metabolized, circulated with significant systemic exposure in CLP rats that received XueBiJing. Among these compounds, hydroxysafflor yellow A, paeoniflorin, oxypaeoniflorin, albiflorin, senkyunolide I, and tanshinol displayed significant anti-sepsis activities, which involved regulating immune responses, inhibiting excessive inflammation, modulating hemostasis, and improving organ function. A combination of the six compounds, with the same respective doses as in XueBiJing, displayed percentage survival and systemic exposure in CLP rats similar to those by XueBiJing. Both the combination and XueBiJing showed high degrees of pharmacokinetic compatibility regarding interactions among the six active compounds and influences of other circulating XueBiJing compounds. The identification of XueBiJing's pharmacologically significant constituents supports the medicine's anti-sepsis use and provides insights into a polypharmacology-based approach to develop medicines for effective sepsis management.

Interferon-α stimulates DExH-box helicase 58 to prevent hepatocyte ferroptosis

BACKGROUND

Liver ischemia/reperfusion (I/R) injury is usually caused by hepatic inflow occlusion during liver surgery, and is frequently observed during war wounds and trauma. Hepatocyte ferroptosis plays a critical role in liver I/R injury, however, it remains unclear whether this process is controlled or regulated by members of the DEAD/DExH-box helicase (DDX/DHX) family.

METHODS

The expression of DDX/DHX family members during liver I/R injury was screened using transcriptome analysis. Hepatocyte-specific Dhx58 knockout mice were constructed, and a partial liver I/R operation was performed. Single-cell RNA sequencing (scRNA-seq) in the liver post I/R suggested enhanced ferroptosis by Dhx58hep-/-. The mRNAs and proteins associated with DExH-box helicase 58 (DHX58) were screened using RNA immunoprecipitation-sequencing (RIP-seq) and IP-mass spectrometry (IP-MS).

RESULTS

Excessive production of reactive oxygen species (ROS) decreased the expression of the IFN-stimulated gene Dhx58 in hepatocytes and promoted hepatic ferroptosis, while treatment using IFN-α increased DHX58 expression and prevented ferroptosis during liver I/R injury. Mechanistically, DHX58 with RNA-binding activity constitutively associates with the mRNA of glutathione peroxidase 4 (GPX4), a central ferroptosis suppressor, and recruits the m6A reader YT521-B homology domain containing 2 (YTHDC2) to promote the translation of Gpx4 mRNA in an m6A-dependent manner, thus enhancing GPX4 protein levels and preventing hepatic ferroptosis.

CONCLUSIONS

This study provides mechanistic evidence that IFN-α stimulates DHX58 to promote the translation of m6A-modified Gpx4 mRNA, suggesting the potential clinical application of IFN-α in the prevention of hepatic ferroptosis during liver I/R injury.

Interleukin-33/serum stimulation-2 pathway: Regulatory mechanisms and emerging implications in immune and inflammatory diseases

Interleukin (IL)- 33, a nuclear factor and pleiotropic cytokine of the IL-1 family, is gaining attention owing to its important role in chronic inflammatory and autoimmune diseases. This review extends our knowledge of the effects exerted by IL-33 on target cells by binding to its specific receptor serum stimulation-2 (ST2). Depending on the tissue context, IL-33 performs multiple functions encompassing host defence, immune response, initiation and amplification of inflammation, tissue repair, and homeostasis. The levels and activity of IL-33 in the body are controlled by complex IL-33-targeting regulatory pathways. The unique temporal and spatial expression patterns of IL-33 are associated with host homeostasis and the development of immune and inflammatory disorders. Therefore, understanding the origin, function, and processes of IL-33 under various conditions is crucial. This review summarises the regulatory mechanisms underlying the IL-33/ST2 signalling axis and its potential role and clinical significance in immune and inflammatory diseases, and discusses the current complex and conflicting findings related to IL-33 in host responses.

Ferritinophagy: A novel insight into the double-edged sword in ferritinophagy-ferroptosis axis and human diseases

Nuclear receptor coactive 4 (NCOA4), which functions as a selective cargo receptor, is a critical regulator of the particularly autophagic degradation of ferritin, a process known as ferritinophagy. Mechanistically, NCOA4-mediated ferritinophagy performs an increasingly vital role in the maintenance of intracellular iron homeostasis by promoting ferritin transport and iron release as needed. Ferritinophagy is not only involved in iron-dependent responses but also in the pathogenesis and progression of various human diseases, including metabolism-related, neurodegenerative, cardiovascular and infectious diseases. Therefore, ferritinophagy is of great importance in maintaining cell viability and function and represents a potential therapeutic target. Recent studies indicated that ferritinophagy regulates the signalling pathway associated with ferroptosis, a newly discovered type of cell death characterised by iron-dependent lipid peroxidation. Although accumulating evidence clearly demonstrates the importance of the interplay between dysfunction in iron metabolism and ferroptosis, a deeper understanding of the double-edged sword effect of ferritinophagy in ferroptosis has remained elusive. Details of the mechanisms underlying the ferritinophagy-ferroptosis axis in regulating relevant human diseases remain to be elucidated. In this review, we discuss the latest research findings regarding the mechanisms that regulate the biological function of NCOA4-mediated ferritinophagy and its contribution to the pathophysiology of ferroptosis. The important role of the ferritinophagy-ferroptosis axis in human diseases will be discussed in detail, highlighting the great potential of targeting ferritinophagy in the treatment of diseases.

Impact of early heparin therapy on mortality in critically ill patients with sepsis associated acute kidney injury: a retrospective study from the MIMIC-IV database

Background: Inflammatory-coagulation dysfunction plays an increasingly important role in sepsis associated acute kidney injury (SAKI). This study aimed to investigate whether early heparin therapy improves survival in patients with SAKI. Methods: Patients with SAKI were identified from the Medical Information Mart for Intensive Care-IV database. The patients were divided into two groups: those who received heparin subcutaneously within 48 h after intensive care unit (ICU) admission and the control group, who received no heparin. The primary endpoint was ICU mortality, the secondary outcomes were 7-day, 14-day, 28-day, and hospital mortality. Propensity score matching (PSM), marginal structural Cox model (MSCM), and E-value analyses were performed. Results: The study included 5623 individuals with SAKI, 2410 of whom received heparin and 3213 of whom did not. There were significant effects on ICU and 28-day mortality in the overall population with PSM. MSCM further reinforces the efficacy of heparin administration reduces ICU mortality in the general population. Stratification analysis with MSCM showed that heparin administration was associated with decreased ICU mortality at various AKI stages. Heparin use was also associated with reduced 28-day mortality in patients with only female, age >60 years, and AKI stage 3, with HRs of 0.79, 0.77, and 0.60, respectively (p < 0.05). E-value analysis suggests robustness to unmeasured confounding. Conclusion: Early heparin therapy for patients with SAKI decreased ICU mortality. Further analysis demonstrated that heparin therapy was associated with reduced 28-day mortality rate in patients only among female, age > 60 years and AKI stage 3.

[Influence of family with sequence similarity 134, member B-mediated reticulophagy on lipopolysaccharide-induced apoptosis of mouse dendritic cells]

Objective: To investigate the influence of family with sequence similarity 134, member B (FAM134B)-mediated reticulophagy on lipopolysaccharide (LPS)-induced apoptosis of mouse dendritic cells (DCs), so as to provide a basis for improving the immune suppression of sepsis caused by wound infection and other factors. Methods: The experimental research methods were used. The DC line DC2.4 of the 3rd to 10th passage in the logarithmic growth stage was collected for experiments. DCs were divided into LPS stimulation 0 h (no stimulation) group, LPS stimulation 6 h group, LPS stimulation 12 h group, LPS stimulation 24 h group, and LPS stimulation 72 h group, which were cultured with 1 μg/mL LPS (the same concentration below) for the corresponding time. The protein expressions of FAM134B, microtubule-associated protein 1 light chain 3B (LC3B), and transporter protein SEC61B were determined by Western blotting, and the ratio of LC3B-Ⅱ/LC3B-Ⅰ was calculated (n=3). DCs were divided into phosphate buffer solution (PBS) group and LPS group for corresponding treatment. After 24 hours of culture, the expression of FAM134B and its co-localization with lysosomal probes and LC3B were detected using immunofluorescence method, while the number of autolysosomes in cells were observed through transmission electron microscope. DCs were divided into the FAM134B-knockdown group that were transfected with lentivirus containing small interfering RNA (siRNA) sequence of FAM134B gene and the empty vector group with empty lentivirus transfected. At post transfection hour 72, the fluorescence expression of cells was observed under the inverted fluorescence phase contrast microscope, meanwhile, the normally cultured DCs were set as blank control group, and the same observation was performed at the corresponding time point. DCs were divided into PBS alone group and LPS alone group, DCs successfully transfected with lentivirus containing siRNA sequence of FAM134B gene were divided into FAM134B-knockdown+PBS group and FAM134B-knockdown+LPS group, and DCs successfully transfected with empty lentivirus were divided into empty vector+PBS group and empty vector+LPS group. These cells were stimulated correspondingly and cultured for 24 hours. The protein expression of FAM134B was detected using Western blotting (n=3); the apoptotic rate of cells was determined by flow cytometry (n=3); the situation of apoptosis was observed by Hoechst staining, and the apoptotic rate was calculated (n=5); the protein expressions of cleaved cysteine aspartic acid specific protease-3 (caspase-3), B cell lymphoma 2 (Bcl-2), and Bcl-2-associated X protein (Bax) were detected using Western blotting, and the ratio of Bax/Bcl-2 was calculated (n=5). Data were statistically analyzed with one-way analysis of variance (ANOVA), least significant difference test, and ANOVA for factorial design. Results: Compared with those in LPS stimulation 0 h group, the protein expressions of FAM134B of cells in LPS stimulation 12 h group and LPS stimulation 24 h group were significantly increased (P<0.05), the protein expressions of SEC61B of cells in LPS stimulation 6 h group, LPS stimulation 12 h group, LPS stimulation 24 h group, and LPS stimulation 72 h group were significantly decreased (P<0.05), and the ratios of LC3B-Ⅱ/LC3B-Ⅰ of cells in LPS stimulation 24 h group and LPS stimulation 72 h group were obviously increased (P<0.05). As the most significant changes of three proteins were seen in the cells of LPS stimulation 24 h group, 24 h was used as the duration of subsequent LPS stimulation. After 24 hours of culture, the expression of FAM134B and its co-localization with LC3B and lysosomal probes in the cells of LPS group were all significantly enhanced, with a significant increase in the number of autolysosomes in comparison with those in PBS group. Both the empty vector group and the FAM134B-knockdown group showed high intensity fluorescence in the cells at post transfection hour 72, but the blank control group showed no fluorescence in the cells at the corresponding time point. After 24 hours of culture, the protein expression of FAM134B of cells in FAM134B-knockdown+PBS group was significantly lower than the expressions in PBS alone group and empty vector+PBS group (with P values all <0.05), the protein expression of FAM134B of cells in FAM134B-knockdown+LPS group was significantly lower than the expressions in LPS alone group and empty vector+LPS group (with P values all <0.05), the protein expression of FAM134B of cells in LPS alone group was significantly higher than that in PBS alone group (P<0.05), while the protein expression of FAM134B of cells in empty vector+LPS group was significantly higher than that in empty vector+PBS group (P<0.05). After 24 hours of culture, flow cytometry assay revealed that the apoptotic rate of cells in PBS alone group, LPS alone group, empty vector+PBS group, empty vector+LPS group, FAM134B-knockdown+PBS group, and FAM134B-knockdown+LPS group were (13.3±0.8)%, (32.6±4.3)%, (17.0±1.5)%, (51.7±3.3)%, (52.4±3.1)%, and (62.3±2.6)%, respectively. After 24 hours of culture, compared with those in LPS alone group and empty vector+LPS group, the protein expression of cleaved caspase-3, the ratio of Bax/Bcl-2, and the apoptotic rates of cells detected by flow cytometry and Hoechst staining were significantly increased in FAM134B-knockdown+LPS group (P<0.05); compared with those in the corresponding PBS treatment group, namely, PBS alone group, empty vector+PBS group, and FAM134B-knockdown+PBS group, the protein expression of cleaved caspase-3, the ratio of Bax/Bcl-2, and the apoptotic rates of cells detected by flow cytometry and Hoechst staining were significantly increased in LPS alone group, empty vector+LPS group, and FAM134B-knockdown+LPS group (P<0.05). Conclusions: The activation of reticulophagy mediated by FAM134B in mouse DCs is enhanced and peaked in 24 hours under LPS stimulation, and the activated reticulophagy has a significant inhibitory effect on cell apoptosis.

[Novel strategy of sepsis immunomodulation targeting dendritic cells]

Dendritic cells (DCs) are the major antigen-presenting cells that play critical roles in regulating both innate and acquire immune responses. In the state of sepsis, the number of DCs is obviously decreased with inhibited antigen presenting ability as well as abnormal cytokine secretion, thereby resulting in an impairment of T lymphocyte activation. Previous studies have demonstrated that the depletion and dysfunction of DCs appear to be the main causes associated with the development of sepsis-induced immunosuppression. Based on the characteristic changes of DCs in sepsis and analysis of recent research progress, the authors propose a novel strategy of immunomodulation targeting the apoptosis, differentiation, and dysfunction of DCs, in order to provide new ideas for the prevention and treatment of severe burns and trauma complicated with sepsis.

Single-cell transcriptome profiling of sepsis identifies HLA-DRlowS100Ahigh monocytes with immunosuppressive function

BACKGROUND

Sustained yet intractable immunosuppression is commonly observed in septic patients, resulting in aggravated clinical outcomes. However, due to the substantial heterogeneity within septic patients, precise indicators in deciphering clinical trajectories and immunological alterations for septic patients remain largely lacking.

METHODS

We adopted cross-species, single-cell RNA sequencing (scRNA-seq) analysis based on two published datasets containing circulating immune cell profile of septic patients as well as immune cell atlas of murine model of sepsis. Flow cytometry, laser scanning confocal microscopy (LSCM) imaging and Western blotting were applied to identify the presence of S100A9⁺ monocytes at protein level. To interrogate the immunosuppressive function of this subset, splenic monocytes isolated from septic wild-type or S100a9^-/- mice were co-cultured with naïve CD4⁺ T cells, followed by proliferative assay. Pharmacological inhibition of S100A9 was implemented using Paquinimod via oral gavage.

RESULTS

ScRNA-seq analysis of human sepsis revealed substantial heterogeneity in monocyte compartments following the onset of sepsis, for which distinct monocyte subsets were enriched in disparate subclusters of septic patients. We identified a unique monocyte subset characterized by high expression of S100A family genes and low expression of human leukocyte antigen DR (HLA-DR), which were prominently enriched in septic patients and might exert immunosuppressive function. By combining single-cell transcriptomics of murine model of sepsis with in vivo experiments, we uncovered a similar subtype of monocyte significantly associated with late sepsis and immunocompromised status of septic mice, corresponding to HLA-DR^lowS100A^high monocytes in human sepsis. Moreover, we found that S100A9⁺ monocytes exhibited profound immunosuppressive function on CD4⁺ T cell immune response and blockade of S100A9 using Paquinimod could partially reverse sepsis-induced immunosuppression.

CONCLUSIONS

This study identifies HLA-DR^lowS100A^high monocytes correlated with immunosuppressive state upon septic challenge, inhibition of which can markedly mitigate sepsis-induced immune depression, thereby providing a novel therapeutic strategy for the management of sepsis.

Effectiveness of early heparin therapy on outcomes in critically ill patients with sepsis-induced coagulopathy

Background: This study aimed to investigate whether early unfractionated heparin (UFH) administration provides a survival advantage for patients with sepsis-induced coagulopathy (SIC). Methods: Patients hospitalized with sepsis-induced coagulopathy from the Medical Information Mart for Intensive Care (MIMIC)-IV database were identified. Patients were divided into two groups, who received unfractionated heparin (UFH) subcutaneously within 24 h after intensive care unit (ICU) admission, and the control group, who received not. The primary endpoint was intensive care unit mortality, the secondary outcomes were 7, 14, and 28-day and hospital mortality. Propensity score matching (PSM) the marginal structural Cox model (MSCM) and E-value analysis were used to account for baseline differences, time-varying and unmeasured confounding factors. Results: A total of 3,377 patients with sepsis-induced coagulopathy were enrolled in the study, of which 815 in unfractionated heparin group and 2,562 in control group. There was significant effect on primary and secondary outcomes with unfractionated heparin after propensity score matching (intensive care unit mortality, hazard ratio [HR] 0.69, 95% confidence interval [CI] 0.52-0.92; 7-day, HR 0.70, 95% CI 0.49-0.99; 14-day, HR 0.68.95% CI 0.50-0.92; 28-day, HR 0.72, 95% CI 0.54-0.96; hospital mortality, HR 0.74, 95% CI 0.57-0.96), marginal structural Cox model manifested unfractionated heparin associated with decreased intensive care unit mortality in all populations (HR 0.64, 95% CI 0.49-0.84), and stratification with the marginal structural Cox model indicated analysis further indicated the survival advantage only among patients with an sepsis-induced coagulopathy score of 4 (HR 0.56, 95% CI 0.38-0.81). Further analysis showed that treatment with 6,250-13750 IU/day of unfractionated heparin associated with a decreased risk of intensive care unit mortality. Similar results were replicated in subgroup analysis with propensity score matching only for patients with an sepsis-induced coagulopathy score of 4 (intensive care unit mortality, HR 0.51, 95% CI 0.34-0.76). Conclusion: This study found early unfractionated heparin therapy to patients with sepsis-induced coagulopathy appears to be associated with improved outcomes. Subgroup analysis further demonstrates heparin therapy decreased intensive care unit mortality primarily in patients only with SIC score of 4.

Nuclear fragile X mental retardation-interacting protein 1-mediated ribophagy protects T lymphocytes against apoptosis in sepsis

Background

Ribophagy is a selective autophagic process that specifically degrades dysfunctional or superfluous ribosomes to maintain cellular homeostasis. Whether ribophagy can ameliorate the immunosuppression in sepsis similar to endoplasmic reticulum autophagy (ERphagy) and mitophagy remains unclear. This study was conducted to investigate the activity and regulation of ribophagy in sepsis and to further explore the potential mechanism underlying the involvement of ribophagy in T-lymphocyte apoptosis.

Methods

The activity and regulation of nuclear fragile X mental retardation-interacting protein 1 (NUFIP1)-mediated ribophagy in T lymphocytes during sepsis were first investigated by western blotting, laser confocal microscopy and transmission electron microscopy. Then, we constructed lentivirally transfected cells and gene-defective mouse models to observe the impact of NUFIP1 deletion on T-lymphocyte apoptosis and finally explored the signaling pathway associated with T-cell mediated immune response following septic challenge.

Results

Both cecal ligation and perforation-induced sepsis and lipopolysaccharide stimulation significantly induced the occurrence of ribophagy, which peaked at 24 h. When NUFIP1 was knocked down, T-lymphocyte apoptosis was noticeably increased. Conversely, the overexpression of NUFIP1 exerted a significant protective impact on T-lymphocyte apoptosis. Consistently, the apoptosis and immunosuppression of T lymphocytes and 1-week mortality rate in NUFIP1 gene-deficient mice were significantly increased compared with those in wild-type mice. In addition, the protective effect of NUFIP1-mediated ribophagy on T lymphocytes was identified to be closely related to the endoplasmic reticulum stress apoptosis pathway, and PERK-ATF4-CHOP signaling was obviously involved in downregulating T-lymphocyte apoptosis in the setting of sepsis.

Conclusions

NUFIP1-mediated ribophagy can be significantly activated to alleviate T lymphocyte apoptosis through the PERK-ATF4-CHOP pathway in the context of sepsis. Thus, targeting NUFIP1-mediated ribophagy might be of importance in reversing the immunosuppression associated with septic complications.

Expert consensus on the monitoring and treatment of sepsis-induced immunosuppression

Emerged evidence has indicated that immunosuppression is involved in the occurrence and development of sepsis. To provide clinical practice recommendations on the immune function in sepsis, an expert consensus focusing on the monitoring and treatment of sepsis-induced immunosuppression was developed. Literature related to the immune monitoring and treatment of sepsis were retrieved from PubMed, Web of Science, and Chinese National Knowledge Infrastructure to design items and expert opinions were collected through an online questionnaire. Then, the Delphi method was used to form consensus opinions, and RAND appropriateness method was developed to provide consistency evaluation and recommendation levels for consensus opinions. This consensus achieved satisfactory results through two rounds of questionnaire survey, with 2 statements rated as perfect consistency, 13 as very good consistency, and 9 as good consistency. After summarizing the results, a total of 14 strong recommended opinions, 8 weak recommended opinions and 2 non-recommended opinions were produced. Finally, a face-to-face discussion of the consensus opinions was performed through an online meeting, and all judges unanimously agreed on the content of this consensus. In summary, this expert consensus provides a preliminary guidance for the monitoring and treatment of immunosuppression in patients with sepsis.

Advances in Immune Monitoring Approaches for Sepsis-Induced Immunosuppression

Sepsis represents a life-threatening organ dysfunction due to an aberrant host response. Of note is that majority of patients have experienced a severe immune depression during and after sepsis, which is significantly correlated with the occurrence of nosocomial infection and higher risk of in-hospital death. Nevertheless, the clinical sign of sepsis-induced immune paralysis remains highly indetectable and ambiguous. Given that, specific yet robust biomarkers for monitoring the immune functional status of septic patients are of prominent significance in clinical practice. In turn, the stratification of a subgroup of septic patients with an immunosuppressive state will greatly contribute to the implementation of personalized adjuvant immunotherapy. In this review, we comprehensively summarize the mechanism of sepsis-associated immunosuppression at the cellular level and highlight the recent advances in immune monitoring approaches targeting the functional status of both innate and adaptive immune responses.

[Rehabilitation strategy for the improvement of long-term outcomes of patients after sepsis]

Survivors of sepsis still face high risks of secondary infection and mortality after hospital discharge. Meanwhile, the persistent cognitive, psychological, and physical disorders affect their long-term outcomes and life qualities. In the current review, we analyze the factors for the poor outcomes and discuss the beneficial rehabilitation strategies to improve the long-term outcomes of patients after sepsis, including psychological intervention, early mobility, nutrition support, and immune modulation, etc.

[Early predictive value of high density lipoprotein cholesterol for secondary acute kidney injury in sepsis patients]

Objective: To investigate the changes of high density lipoprotein cholesterol (HDL-C) in sepsis patients and its early predictive value for secondary acute kidney injury (AKI) in such patients. Methods: A retrospective case series study was conducted. From June 2019 to June 2021, 232 sepsis patients who met the inclusion criteria were admitted to the Second Hospital of Hebei Medical University, including 126 males and 106 females, aged 24 to 71 years. According to whether complicating secondary AKI, the patients were divided into non-AKI group (n=158) and AKI group (n=74). Data of patients between the two groups were compared and statistically analyzed with independent sample t test or chi-square test, including the sex, age, body mass index (BMI), body temperature, heart rate, primary infection site, combined underlying diseases, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score and sepsis-related organ failure assessment (SOFA) score at admission, and the serum levels of C-reactive protein (CRP), procalcitonin, creatinine, cystatin C, and HDL-C measured at diagnosis of sepsis. The multivariate logistic regression analysis was performed on the indicators with statistically significant differences between the two groups to screen the independent risk factors for developing secondary AKI in 232 sepsis patients, and the joint prediction model was established based on the independent risk factors. The receiver operating characteristic (ROC) curve of the independent risk factors and the joint prediction model predicting secondary AKI in 232 sepsis patients were drawn, and the area under the curve (AUC), the optimal threshold, and the sensitivity and specificity under the optimal threshold were calculated. The quality of the above-mentioned AUC was compared by Delong test, and the sensitivity and specificity under the optimal threshold were compared using chi-square test. Results: The sex, age, BMI, body temperature, heart rate, primary infection site, combined underlying diseases, and CRP level of patients between the two groups were similar (P>0.05). The procalcitonin, creatinine, cystatin C, and scores of APACHE Ⅱ and SOFA of patients in AKI group were all significantly higher than those in non-AKI group (with t values of -3.21, -16.14, -12.75, -11.13, and -12.88 respectively, P<0.01), while the HDL-C level of patients in AKI group was significantly lower than that in non-AKI group (t=6.33, P<0.01). Multivariate logistic regression analysis showed that creatinine, cystatin C, and HDL-C were the independent risk factors for secondary AKI in 232 sepsis patients (with odds ratios of 2.45, 1.68, and 2.12, respectively, 95% confidence intervals of 1.38-15.35, 1.06-3.86, and 0.86-2.56, respectively, P<0.01). The AUCs of ROC curves of creatinine, cystatin C, HDL-C, and the joint prediction model for predicting secondary AKI in 232 sepsis patients were 0.69, 0.79, 0.89, and 0.93, respectively (with 95% confidence intervals of 0.61-0.76, 0.72-0.85, 0.84-0.92, and 0.89-0.96, respectively, P values all below 0.01); the optimal threshold were 389.53 μmol/L, 1.56 mg/L, 0.63 mmol/L, and 0.48, respectively; the sensitivity under the optimal threshold were 76.6%, 81.4%, 89.7%, and 95.5%, respectively; the specificity under the optimal threshold values were 78.6%, 86.7%, 88.6%, and 96.6%, respectively. The AUC quality of cystatin C was significantly better than that of creatinine (z=2.34, P<0.05), the AUC quality and sensitivity and specificity under the optimal threshold of HDL-C were all significantly better than those of cystatin C (z=3.33, with χ2 values of 6.43 and 7.87, respectively, P<0.01) and creatinine (z=5.34, with χ2 values of 6.32 and 6.41, respectively, P<0.01); the AUC quality and sensitivity and specificity under the optimal threshold of the joint prediction model were all significantly better than those of creatinine, cystatin C, and HDL-C (with z values of 6.18, 4.50, and 2.06, respectively, χ2 values of 5.31, 7.23, 3.99, 6.56, 7.34, and 4.00, respectively, P<0.05 or P<0.01). Conclusions: HDL-C level in sepsis patients with secondary AKI is significantly lower than that in patients without secondary AKI. This is an independent risk factor for secondary AKI in sepsis patients with a diagnostic value being superior to that of creatinine and cystatin C. The combination of the aforementioned three indicators would have higher predicative valuable for secondary AKI in sepsis patients.

Sestrin2 protects against lethal sepsis by suppressing the pyroptosis of dendritic cells

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Sestrin2 (SESN2), a highly evolutionarily conserved protein, is critically involved in the cellular response to various stresses and has been confirmed to maintain the homeostasis of the internal environment. However, the potential effects of SESN2 in regulating dendritic cells (DCs) pyroptosis in the context of sepsis and the related mechanisms are poorly characterized. In this study, we found that SESN2 was capable of decreasing gasdermin D (GSDMD)-dependent pyroptosis of splenic DCs by inhibiting endoplasmic reticulum (ER) stress (ERS)-related nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)-mediated ASC pyroptosome formation and caspase-1 (CASP-1) activation. Furthermore, SESN2 deficiency induced NLRP3/ASC/CASP-1-dependent pyroptosis and the production of proinflammatory cytokines by exacerbating the PERK–ATF4–CHOP signaling pathway, resulting in an increase in the mortality of septic mice, which was reversed by inhibiting ERS. These findings suggest that SESN2 appears to be essential for inhibiting NLRP3 inflammasome hyperactivation, reducing CASP-1-dependent pyroptosis, and improving sepsis outcomes through stabilization of the ER. The present study might have important implications for exploration of novel potential therapeutic targets for the treatment of sepsis complications.

Efficiency of Monocyte/High-Density Lipoprotein Cholesterol Ratio Combined With Neutrophil/Lymphocyte Ratio in Predicting 28-Day Mortality in Patients With Sepsis

Background: Sepsis can cause unpredictable harm, and early identification of risk for mortality may be conducive to clinical diagnosis. The present study proposes to assess the efficacy of the monocyte/high-density lipoprotein cholesterol ratio (MHR) combined with the neutrophil/lymphocyte ratio (NLR) on the day of admission in predictive efficacy in the 28-day mortality risk in critical patients with sepsis.

Material and Methods: We administered observational and retrospective cohort research from a single center. The correlation of the clinical variables, together with the system severity scores of APACHE II and SOFA, are displayed by correlation analysis, and a Cox regression model could be performed to screen the independent risk factors and estimate the capacity of multiple markers in predicting 28-day mortality. The receiver operating characteristic (ROC) curve served as an applied method to output cutoff values for the diagnosis and prognostic risk, and the area under the ROC curve and net reclassification improvement index (NRI), as well as integrated discrimination improvement index (IDI) were employed to assess the feasibility of multiple parameters for predictive value in 28-day mortality of septic patients.

Results: The study enrolled 274 eligible patients with sepsis. The correlation analysis indicated NLR and MHR were related to the sepsis severity. A multivariate Cox regression analysis indicated that NLR together with MHR displayed a close relation to death rate after adjusting for other potential confounders (NLR, HR = 1.404 [95% CI 1.170–1.684], P < 0.001; MHR, HR = 1.217 [95% CI 1.112–1.331], P < 0.001). The AUC of NLR, MHR, NLR_MHR was 0.827, 0.876, and 0.934, respectively. The addition on the biomarker NLR_MHR to the prediction model improved IDI by 18.5% and NRI by 37.8%.

Conclusions: Our findings suggest that NLR and MHR trend to an elevated level in non-surviving patients with sepsis. Evaluation of NLR_MHR, an independent risk factor for increased mortality, might improve the predictive efficacy for 28-day mortality risk in septic patients.

TNF-α-induced protein 8-like 2 negatively regulates the immune function of dendritic cells by suppressing autophagy via the TAK1/JNK pathway in septic mice

Tumor necrosis factor (TNF)-α-induced protein 8-like 2 (TIPE2) is a newly discovered negative immunoregulatory protein that is involved in various cellular immune responses to infections. However, the underlying mechanism by which TIPE2 affects the immune function of dendritic cells (DCs) is not yet understood. This study aimed to determine the correlations among DCs TIPE2 expression, autophagic activity and immune function in the context of sepsis. In addition, the signaling pathway by which TIPE2 regulates autophagy in DCs was investigated. We reported for the first time that TIPE2 overexpression (knock-in, KI) exerted an inhibitory effect on autophagy in DCs and markedly suppressed the immune function of DCs upon septic challenge both in vitro and in vivo. In addition, TIPE2 knockout (KO) in DCs significantly enhanced autophagy and improved the immune response of DCs in sepsis. Of note, we found that the transforming growth factor-β (TGF-β)-activated kinase-1 (TAK1)/c-Jun N-terminal kinase (JNK) pathway was inhibited by TIPE2 in DCs, resulting in downregulated autophagic activity. Collectively, these results suggest that TIPE2 can suppress the autophagic activity of DCs by inhibiting the TAK1/JNK signaling pathway and further negatively regulate the immune function of DCs in the development of septic complications.

Antagonism of Cerebral High Mobility Group Box 1 Ameliorates Dendritic Cell Dysfunction in Sepsis

Sepsis has emerged as a global health issue, and accounts for millions of deaths in intensive care units. Dysregulation of the immune response reportedly contributes to the pathogenesis and progression of this lethal condition, which involves both the dysfunction of immune cells and incompetent immunomodulatory mechanisms. High mobility group box 1 (HMGB1) is known as a later inflammatory mediator and is critically involved in the severity and prognosis of sepsis by inducing intractable inflammation and dysfunction of various immune cells. In the present study, we found that intracerebroventricular (ICV) injection of Box A, a specific antagonist of HMGB1, restored the dysregulated response of splenic dendritic cells (DCs) in septic mice by enhancing the expression of surface molecules, including CD80, CD86, and MHC-II, as well as improving DC priming of T lymphocytes. Cerebral HMGB1 was also confirmed to have potent inhibitory effects on DC functions when administrated by ICV injection in normal mice. The brain cholinergic system was found to mediate the immunomodulatory effects of central HMGB1, as it exhibited enhanced activity with persistent HMGB1 exposure. Furthermore, the inhibitory effects of cerebral HMGB1 on the response of peripheral DCs were also blocked by α7nAchR gene knockout. These findings provide novel insight into the relationship between cerebral HMGB1 and splenic DC dysfunction during sepsis, which is, at least in part, dependent on cholinergic system activity.

The Role and Regulatory Mechanism of Transcription Factor EB in Health and Diseases

Transcription factor EB (TFEB) is a member of the microphthalmia-associated transcription factor/transcription factor E (MiTF/TFE) family and critically involved in the maintenance of structural integrity and functional balance of multiple cells. In this review, we described the effects of post-transcriptional modifications, including phosphorylation, acetylation, SUMOylation, and ubiquitination, on the subcellular localization and activation of TFEB. The activated TFEB enters into the nucleus and induces the expressions of targeted genes. We then presented the role of TFEB in the biosynthesis of multiple organelles, completion of lysosome-autophagy pathway, metabolism regulation, immune, and inflammatory responses. This review compiles existing knowledge in the understanding of TFEB regulation and function, covering its essential role in response to cellular stress. We further elaborated the involvement of TFEB dysregulation in the pathophysiological process of various diseases, such as the catabolic hyperactivity in tumors, the accumulation of abnormal aggregates in neurodegenerative diseases, and the aberrant host responses in inflammatory diseases. In this review, multiple drugs have also been introduced, which enable regulating the translocation and activation of TFEB, showing beneficial effects in mitigating various disease models. Therefore, TFEB might serve as a potential therapeutic target for human diseases. The limitation of this review is that the mechanism of TFEB-related human diseases mainly focuses on its association with lysosome and autophagy, which needs deep description of other mechanism in diseases progression after getting more advanced information.

Sestrin2 protects dendrite cells against ferroptosis induced by sepsis

Ferroptosis is a nonapoptotic form of programmed cell death triggered by the accumulation of reactive oxygen species (ROS) depended on iron overload. Although most investigations focus on the relationship between ferroptosis and cancer, neurodegenerative diseases, and ischemia/reperfusion injury, research on ferroptosis induced by immune-related inflammatory diseases, especially sepsis, is scarce. Sestrin2 (Sesn2), a highly evolutionary and stress-responsive protein, is critically involved in defense against oxidative stress challenges. Upregulated expression of Sesn2 has been observed in preliminary experiments to have an antioxidative function in the context of an inflammatory response. Nevertheless, the underlying function of Sesn2 in inflammation-mediated ferroptosis in the immune system remains uncertain. The current study aimed to demonstrate the protective effect of Sesn2 on ferroptosis and even correlations with ferroptosis and the functions of ferroptotic-dendritic cells (DCs) stimulated with lipopolysaccharide (LPS). The mechanism underlying DCs protection from LPS-induced ferroptosis by Sesn2 was further explored in this study. We found that the immune response of DCs assessed by co-stimulatory phenotypes was gradually enhanced at the peak time of 12 h upon 1 μg/ml LPS stimulation while ferroptosis in DCs treated with LPS at 24 h was significantly detected. LPS-induced ferroptosis showed a suppressive impact on DCs in phenotypic maturation, which was conversely relieved by the ferroptotic inhibitor. Compared with wild-type (WT) mice, DCs in genetic defective mice of Sesn2 (Sesn2-/-) exhibited exacerbated ferroptosis. Furthermore, the protective effect of Sesn2 on ferroptosis was noticed to be associated with the ATF4-CHOP-CHAC1 pathway, eventually exacerbating ferroptosis by degrading of glutathione. These results indicate that Sesn2 can suppress the ferroptosis of DCs in sepsis by downregulating the ATF4-CHOP-CHAC1 signaling pathway, and it might play an antioxidative role.

Update Advances on C-Reactive Protein in COVID-19 and Other Viral Infections

Severe coronavirus disease 2019 (COVID-19) can manifest as a viral-induced hyperinflammation with multiorgan dysfunction. It has been documented that severe COVID-19 is associated with higher levels of inflammatory mediators than a mild disease, and tracking these markers may allow early identification or even prediction of disease progression. It is well known that C-reactive protein (CRP) is the acute-phase protein and the active regulator of host innate immunity, which is highly predictive of the need for mechanical ventilation and may guide escalation of treatment of COVID-19-related uncontrolled inflammation. There are numerous causes of an elevated CRP, including acute and chronic responses, and these can be infectious or non-infectious in etiology. CRP are normally lacking in viral infections, while adaptive immunity appears to be essential for COVID-19 virus clearance, and the macrophage activation syndrome may explain the high serum CRP contents and contribute to the disease progression. Nevertheless, for the assessment of host inflammatory status and identification of viral infection in other pathologies, such as bacterial sepsis, the acute-phase proteins, including CRP and procalcitonin, can provide more important information for guiding clinical diagnosis and antibiotic therapy. This review is aimed to highlight the current and most recent studies with regard to the clinical significance of CRP in severe COVID-19 and other viral associated illnesses, including update advances on the implication of CRP and its form specifically on the pathogenesis of these diseases. The progressive understanding in these areas may be translated into promising measures to prevent severe outcomes and mitigate appropriate treatment modalities in critical COVID-19 and other viral infections.

[New understanding on the immunity for severe infections and complications in burns and trauma]

The mechanisms of burn/trauma related infection are complicated, involving uncontrolled inflammation, immune disorder, coagulation abnormality, and pathophysiological changes of multiple systems or organs. Although active management of primary diseases, application of antibiotics, and organ support treatment are the basis for the management of burn/trauma related infection, immune modulation opens up a new direction for the intervention of burn/trauma related infection and the relevant complications. In-depth understanding of inflammation-immune response and its regulatory mechanisms, and exploring new early warning biomarkers and immune interventional strategies are of great significance for improving the level of treatment of clinical burn/trauma related infections and improving the prognosis of patients.

Is oxygen therapy beneficial for normoxemic patients with acute heart failure? A propensity score matched study

BACKGROUND

The clinical efficiency of routine oxygen therapy is uncertain in patients with acute heart failure (AHF) who do not have hypoxemia. The aim of this study was to investigate the association between oxygen therapy and clinical outcomes in normoxemic patients hospitalized with AHF using real-world data.

METHODS

Normoxemic patients diagnosed with AHF on ICU admission from the electronic ICU (eICU) Collaborative Research Database were included in the current study, in which the study population was divided into the oxygen therapy group and the ambient-air group. Propensity score matching (PSM) was applied to create a balanced covariate distribution between patients receiving supplemental oxygen and those exposed to ambient air. Linear regression and logistic regression models were performed to assess the associations between oxygen therapy and length of stay (LOS), and all-cause in-hospital as well as ICU mortality rates, respectively. A series of sensitivity and subgroup analyses were conducted to further validate the robustness of our findings.

RESULTS

A total of 2922 normoxemic patients with AHF were finally included in the analysis. Overall, 42.1% (1230/2922) patients were exposed to oxygen therapy, and 57.9% (1692/2922) patients did not receive oxygen therapy (defined as the ambient-air group). After PSM analysis, 1122 pairs of patients were matched: each patient receiving oxygen therapy was matched with a patient without receiving supplemental oxygen. The multivariable logistic model showed that there was no significant interaction between the ambient air and oxygen group for all-cause in-hospital mortality [odds ratio (OR) 1.30; 95% confidence interval (CI) 0.92-1.82; P = 0.138] or ICU mortality (OR 1.39; 95% CI 0.83-2.32; P = 0.206) in the post-PSM cohorts. In addition, linear regression analysis revealed that oxygen therapy was associated with prolonged ICU LOS (OR 1.11; 95% CI 1.06-1.15; P <  0.001) and hospital LOS (OR 1.06; 95% CI 1.01-1.10; P = 0.009) after PSM. Furthermore, the absence of an effect of supplemental oxygen on mortality was consistent in all subgroups.

CONCLUSION

Routine use of supplemental oxygen in AHF patients without hypoxemia was not found to reduce all-cause in-hospital mortality or ICU mortality.

[Deepening the understanding of the diagnostic system and therapeutic strategy for burn sepsis]

Burn patients with large area of skin defect are prone to cause wound infection, severe fluid loss, and hypermetabolism, etc, which lead to sequential dysfunction of multiple systems and easily induce severe systemic infections and sepsis. At present, sepsis has been the leading causes of death in severe burn patients, and its early diagnosis and timely treatment are critical for successful treatment of patients. As burn sepsis has unique pathophysiological characteristics, the diagnostic criteria for general sepsis lack specificity for burn sepsis. Therefore, to understand the pathogenesis of burn will help deepen the understanding of the diagnostic system and interventional way of burn sepsis, thus developing more precise and intelligent therapeutic strategy.

ER stress and its PERK branch enhance TCR-induced activation in regulatory T cells

Although accumulating evidence indicates participation of endoplasmic reticulum (ER) stress pathway or the unfolded protein response (UPR) in immunity, there still exists little information linking ER stress to regulatory T cells (Tregs). To evaluate the potential contribution of the UPR, we tested the effects of thapsigargin (TG), an ER stress inducer, on the function of Tregs. Here we reported that TG stimulation induced the up-regulation of the endoplasmic reticulum (ER)-stress chaperon Glucose-Regulated Protein 78 (GRP78), which is a master regulator of the UPR, the phosphorylation of eukaryotic initiation factor 2 alpha (elF2α) and the induction of activating transcription factor 4 (ATF4), which are both protein kinase R (PKR)-like ER kinase (PERK) downstream targets in Tregs. Simultaneously, we demonstrated that, under ER stress conditions, Tregs presented enhanced functional activity upon TCR stimulation, as illustrated with forkhead box transcription factor (Foxp3) expression, interleukin-10 (IL-10) and transforming growth factor-β (TGF-β) production and suppressive functional analysis. Notably, pretreatment with GSK2656157, a potent and selective PERK inhibitor, markedly diminished the TG-induced hyperresponsiveness of Tregs upon T cell antigen receptor (TCR) stimulation. Therefore, our findings illustrated the inter-connection and coordination of the evolutionarily conserved ER stress response and TCR signaling in Tregs and uncover a critical new role of the PERK branch of UPR in the regulation of Tregs function.

[Analysis on prediction power of HIV infection risk assessment tool in men who have sex with men in Guizhou province]

Objective: To evaluate the prediction power of HIV infection risk assessment tool and the applicability in MSM in Guizhou province. Methods: MSM were recruited through snowball sampling method. Questionnaire surveys were conducted among the MSM using HIV infection risk assessment tool, and combined with HIV serologic test results, the risk prediction power of HIV infection risk assessment tool was evaluated. Results: A total of 3 379 MSM were recruited from January 2018 to December 2019 in Guizhou. The HIV infection rate was 3.3%(111/3 379). The mean risk scores of HIV positive and HIV negative MSM were (12.15±3.08) and (12.07±3.07), respectively. The difference in risk score was significant between MSM with different HIV status (t=8.69, P<0.001). According to the principle of decision tree, individual risk scores were divided into following three categories: ≤11.96, 11.97-14.80 and >14.80, the HIV infection rate was 0.8%, 4.3% and 8.6% respectively, suggesting that the higher the individual risk score was, the higher the HIV infection rate was (trend χ²=88.18, P<0.001). Multivariate logistic regression analysis showed that the higher the individual risk score was, the higher the risk of HIV infection was. Compared to the total score ≤11.96, the aOR values at total scores of 11.97-14.80 and >14.80 were 6.34 (95%CI: 3.38-11.88) and 14.07(95%CI: 7.44-26.61), respectively. The risk of HIV infection in Miao ethnic group was higher than that in Han ethnic group (aOR=1.83, 95%CI:1.04-3.21), and the risk of HIV infection in those with education level of primary school and below was higher than that in undergraduates or those with education level of junior college and above (aOR=2.50, 95%CI:1.06-5.88), and the risk of HIV infection was higher in those who had bisexual behaviors than in those who had homosexual behaviors (aOR=1.95, 95%CI:1.19-3.19). The risk of HIV infection was higher in those who had never received HIV testing (aOR=1.53, 95%CI:1.01-2.33). The area under the receiver operating characteristic (ROC) curve and area under ROC (AUC) for HIV infection prediction was 0.751 (95%CI:0.710-0.792, P<0.001). The maximum Youden's index was individual risk score of 12.56, and the sensitivity of the risk assessment tool was 0.838, and its specificity was 0.412. Conclusions: The results of HIV infection risk assessment tool in Guizhou indicated that in MSM the higher the individual risk score, the higher the risk of HIV infection is. The tool can be used to evaluate the risk of HIV infection in MSM, but the specificity should be improved.

The Essential Involvement of the Omentum in the Peritoneal Defensive Mechanisms During Intra-Abdominal Sepsis

Although the abilities of the omentum to alleviate inflammation and prevent infection have been revealed over the past decades, the underlying mechanisms remain largely unelucidated. Here, we demonstrated that the mortality of mice exposed to cecal ligation and puncture (CLP) and omentectomy was remarkably increased compared to those treated with CLP alone. Moreover, the efficacy of the omentum was associated with an impairment in intraperitoneal bacterial clearance together with an increase in the expression of proinflammatory cytokines. Besides, in response to peritoneal infections, the size and quantity of the omental milky spots (MSs) were increased tremendously and they also support innate-like B1 cell responses and local IgM production in the peritoneal cavity. Furthermore, not only the migration but also the functional activities of neutrophils were diminished in the absence of the omentum. These data collectively show that the omentum contributes more to peritoneal immune responses during septic peritonitis than has heretofore been recognized. Thus, harnessing the function of MS-containing omentum to increase its protective effectiveness may exert important biological and therapeutic implications for the control of intra-abdominal infections.

Clinical Efficacy and Safety of Hyperthermic Intraperitoneal Chemotherapy in Colorectal Cancer Patients at High Risk of Peritoneal Carcinomatosis: A Systematic Review and Meta-Analysis

Background: Hyperthermic intraperitoneal chemotherapy (HIPEC) is an effective measure for improving the prognosis of colorectal cancer (CRC) patients with peritoneal carcinomatosis (PC). However, the role of HIPEC in CRC patients at high risk of PC remains controversial. The current systematic review and meta-analysis aimed to evaluate the clinical efficacy and safety of HIPEC in CRC patients at high risk of PC. Methods: We performed a systematic search of PubMed, Embase, Cochrane Library, and other online databases up to July 30, 2020. The clinical data, including overall survival, disease free survival, peritoneal metastasis rate, and postoperative adverse reaction were screened and analyzed after data extraction. Risk ratios (RRs) were applied to analyze these dichotomous outcomes with a random effects model. Results: A total of 6 available clinical studies involving 603 patients were finally included. CRC patients at high risk of PC who proactively underwent HIPEC treatment showed a significantly reduced peritoneal metastasis rate (RR: 0.41, 95% CI: 0.21-0.83, P = 0.01; I ² = 58%) compared to the similarly high-risk in CRC patients who did not receive HIPEC treatment. However, in terms of overall survival (RR: 1.13, 95% CI: 0.97-1.33, P = 0.12; I ² = 77%), disease-free survival (RR: 1.10, 95% CI: 0.75-1.59, P = 0.63; I ² = 53%), progression free survival (RR: 1.85, 95% CI: 0.48-7.14, P = 0.37; I ² = 93%), and postoperative adverse reactions (RR: 0.1.07, 95% CI: 0.36-3.15, P = 0.90; I ² = 78%), there was no significant difference between the HIPEC treatment and control groups. Conclusions: Proactive HIPEC treatment did not show the expected clinical efficacy in prolonging the overall survival time, disease-free survival time, and progression-free survival time of CRC patients at high risk of PC. However, the preemptive administration of HIPEC was associated with a reduced peritoneal metastasis rate and did not cause adverse additional postoperative effects.

[A survey on sexual needs and factors of HIV risky sexual behaviors among elderly men at different ages in two communities of Qiandongnan Miao and Dong autonomous prefecture]

Objective: To understand sexual needs and factors of risky sexual behaviors among elderly men at different ages in two communities of Qiandongnan Miao and Dong autonomous prefecture and provide basis for targeted HIV prevention and intervention. Methods: Two communities in the prefecture were selected as study sites. Questionnaire surveys were carried out among elderly men aged 50 and over who visited or consulted in the communities from June to December 2018, and they were tested for HIV and syphilis antibodies. Results: Among 400 elderly men, 209 (52.2%) were 50-64 years old, and 191(47.8%) were above 65 years old. They were mainly Miao people, accounting for 66.3% (265/400), and 235 (58.8%) had an education no more than 6 years. HIV awareness of the two age groups were only 25.8% (54/199) and 26.2% (50/191), respectively. Among those aged 50-64, 142 (68.0%) felt normal sexual desire, and 153 (73.6%) reported penile erections or erections in most cases whenever sex, and 52.9% (110) ejaculated most of the time. HIV prevalence was 1.0% (4/400). Compared with the over 65-year-old group, the proportion of having sex with spouse/stable partners (89.5%, 179/200), proportion of no condom use with their spouse/stable sexual partners during the most recent sex (93.8%, 168/179), proportion of having casual sex (11.0%, 23/209) and commercial sex (3.8%, 8/209) were all higher among 50-64 age group. In comparison to those aged over 65 years old, average monthly income>3 000, and use of sex helper, aged 50-64 (OR=2.70, 95%CI: 1.22-5.95), average monthly income ≤1 000 yuan (OR=2.79, 95%CI: 1.25-6.21), and no use of sex helper (OR=3.78) (95%CI: 1.65-8.67) were related factors of HIV risky sexual behavior last time. Conclusion: Elderly men in the minority prefecture had low HIV awareness. Compared with those≥65 years old, the 50-64 age group had more active sexual behaviors and higher sexual needs. Those from 50-64 age group, with lower economic level and good sexual ability were more likely to have HIV risky sexual behaviors.

The Clinical Features and Prognostic Assessment of SARS-CoV-2 Infection-Induced Sepsis Among COVID-19 Patients in Shenzhen, China

Background: The outbreak of the novel coronavirus disease (COVID-19) that began in December 2019 has posed a great threat to human health and caused a significant loss of life. In Shenzhen, 465 patients were confirmed to have COVID-19 as of August 31, 2020. In the present study, we aimed to describe the clinical characteristics of COVID-19 patients in Shenzhen and identify risk factors for the development of viral sepsis.

Methods: In this retrospective study, patients who were confirmed to have a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and were admitted to the Third People's Hospital of Shenzhen from January 11 to April 27, 2020 were included in the cohort. Clinical data were extracted and followed up to May 10, 2020, by using predesigned data collection forms.

Results: A total of 422 hospitalized COVID-19 patients were enrolled in this study, including 97 (23%) patients with viral sepsis at hospital admission and 325 (77%) non-septic patients. Patients with sepsis were much older than those without sepsis (57 vs. 43 years, P < 0.001) and presented with more comorbidities. Septic patients showed multiple organ dysfunction and significant abnormalities in immune- and inflammation-related biomarkers, and had poorer outcomes when compared to those without sepsis. Increased levels of interleukin-6, blood urea nitrogen, and creatine kinase were associated with the development of SARS-CoV-2-induced sepsis, and an elevated production of interleukin-6 was found to be an independent risk factor for the progression to critical illness among septic COVID-19 patients.

Conclusions: SARS-CoV-2 infection-induced sepsis is critically involved in the severity and prognosis of COVID-19 patients by characterizing both aberrant immune response and uncontrolled inflammation. The development of sepsis might contribute to multiple organ dysfunction and poor outcomes in COVID-19 patients during hospitalization.

Effect of Interleukin-36β on Activating Autophagy of CD4+CD25+ Regulatory T cells and Its Immune Regulation in Sepsis

BACKGROUND

CD4+CD25+ regulatory T cells (Tregs) play an essential role in sepsis-induced immunosuppression. How, the effects of interleukin 36 (IL-36) cytokines on CD4+CD25+ Tregs and their underlying mechanism(s) in sepsis remain unknown.

METHODS

Our study was designed to investigate the impacts of IL-36 cytokines on murine CD4+CD25+ Tregs in presence of lipopolysaccharide (LPS) and in a mouse model of sepsis induced by cecal ligation and puncture (CLP). IL-36-activated autophagy was evaluated by autophagy markers, autophagosome formation, and autophagic flux.

RESULTS

IL-36α, IL-36β, and IL-36γ were expressed in murine CD4+CD25+ Tregs. Stimulation of CD4+CD25+ Tregs with LPS markedly up-regulated the expression of these cytokines, particularly IL-36β. IL-36β strongly suppressed CD4+CD25+ Tregs under LPS stimulation and in septic mice challenged with CLP, resulting in the amplification of T-helper 1 response and the proliferation of effector T cells. Mechanistic studies revealed that IL-36β triggered autophagy of CD4+CD25+ Tregs. These effects were significantly attenuated in the presence of the autophagy inhibitor 3-methyladenine or Beclin1 knockdown. In addition, early IL-36β administration reduced the mortality rate in mice subjected to CLP. Depletion of CD4+CD25+ Tregs before the onset of sepsis obviously abrogated IL-36β-mediated protection against sepsis.

CONCLUSIONS

These findings suggest that IL-36β diminishes the immunosuppressive activity of CD4+CD25+ Tregs by activating the autophagic process, thereby contributing to improvement of the host immune response and prognosis in sepsis.

Lysosomal quality control of cell fate: a novel therapeutic target for human diseases

In eukaryotic cells, lysosomes are digestive centers where biological macromolecules are degraded by phagocytosis and autophagy, thereby maintaining cellular self-renewal capacity and energy supply. Lysosomes also serve as signaling hubs to monitor the intracellular levels of nutrients and energy by acting as platforms for the assembly of multiple signaling pathways, such as mammalian target of rapamycin complex 1 (mTORC1) and adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK). The structural integrity and functional balance of lysosomes are essential for cell function and viability. In fact, lysosomal damage not only disrupts intracellular clearance but also results in the leakage of multiple contents, which pose great threats to the cell by triggering cell death pathways, including apoptosis, necroptosis, pyroptosis, and ferroptosis. The collapse of lysosomal homeostasis is reportedly critical for the pathogenesis and development of various diseases, such as tumors, neurodegenerative diseases, cardiovascular diseases, and inflammatory diseases. Lysosomal quality control (LQC), comprising lysosomal repair, lysophagy, and lysosomal regeneration, is rapidly initiated in response to lysosomal damage to maintain lysosomal structural integrity and functional homeostasis. LQC may be a novel but pivotal target for disease treatment because of its indispensable role in maintaining intracellular homeostasis and cell fate.

[Influence of Xuebijing injection and its component paeoniflorin on immune function and survival rate of septic rats]

Objective: To explore the influence of Xuebijing injection (hereinafter referred to as Xuebijing) and its component paeoniflorin on immune function of regulatory T cells (Tregs) of spleen and survival rate of septic rats. Methods: (1) CD4(+) CD25(+) Tregs and CD4(+) T cells were isolated and purified from spleens of three 9 to 12 weeks old Sprague-Dawley male rats (the same age, breed, and gender below) by immunomagnetic beads. According to the random number table (the same grouping method below), CD4(+) CD25(+) Tregs were divided into blank control group, simple CD3/CD28 group, simple endotoxin/lipopolysaccharide (LPS) group, LPS+ Xuebijing group, and LPS+ paeoniflorin group, with 6 wells in each group. The cells in simple CD3/CD28 group, simple LPS group, LPS+ Xuebijing group, and LPS+ paeoniflorin group were cultured in RPMI 1640 medium containing fetal bovine serum in volume fraction of 10%, 1.25 μg CD3, and 2.5 μg CD28 for 24 hours. Then 1 μg/mL LPS in the volume of 1 μL was added to the cells in simple LPS group, LPS+ Xuebijing group, and LPS+ paeoniflorin group. Moreover, 5 mg/mL Xuebijing in the volume of 1 μL and 80 μmol/L paeoniflorin in the volume of 1 μL were added to the cells in LPS+ Xuebijing group and LPS+ paeoniflorin group, respectively, which were cultured for another 72 hours. Cells in blank control group were routinely cultured in RPMI 1640 medium containing fetal bovine serum in volume fraction of 10% for 96 hours. The expressions of cytotoxic T lymphocyte antigen 4 (CTLA-4) and forkhead wing-link transcription factor 3 (Foxp3) and apoptosis of CD4(+) CD25(+) Tregs were measured by flow cytometry. The interleukin-10 (IL-10) level from culture supernatant of CD4(+) CD25(+) Tregs was determined by enzyme-linked immunosorbent assay (ELISA). CD4(+) T cells were divided into blank control' group, simple CD3/CD28' group, simple LPS' group, LPS+ Xuebijing' group, and LPS+ paeoniflorin' group, with 6 wells in each group. After being cocultured with the corresponding CD4(+) CD25(+) Tregs treated as before for 72 hours, the proliferative activity of CD4(+) T cells was measured by flow cytometry, and IL-4 level from culture supernatant of CD4(+) T cells was determined by ELISA. (2) One hundred and twenty rats were divided into sham surgery group, simple sepsis group, sepsis+ Xuebijing group, and sepsis+ paeoniflorin group, with 30 rats in each group. The septic rat model was reproduced by cecal ligation and puncture surgery in simple sepsis group, sepsis+ Xuebijing group, and sepsis+ paeoniflorin group. In sham surgery group, the rats were only performed with laparotomy to simulate surgery. In sepsis+ Xuebijing group, the rats were given post-surgical injection of 4 mL/kg Xuebijing through tail vein, twice a day. In sepsis+ paeoniflorin group, the rats received 978 μg paeoniflorin via tail vein, twice a day. The survival rates of rats in the four groups on post surgery day 1, 2, 3, 4, 5, 6, and 7 were observed and recorded. The surviving cure of Kaplan-Meier was drawn. Data were statistically analyzed with one-way analysis of variance, least significant difference t test. The surviving curve was analyzed by Log-rank (Mantel-Cox) test. Results: (1) Compared with those in blank control group, the expressions of CTLA-4 and Foxp3 of CD4(+) CD25(+) Tregs (t=27.19, 17.00, P<0.01) and IL-10 level from culture supernatant (t=40.76, P<0.01) were significantly increased in rats in simple LPS group. Compared with those in simple LPS group, the expressions of CTLA-4 and Foxp3 of CD4(+) CD25(+) Tregs (t(LPS+ Xuebijing group)=31.03, 11.27, t(LPS+ paeoniflorin group)=5.79, 5.64, P<0.01) and IL-10 level from culture supernatant (t=15.49, 4.20, P<0.01) was significantly decreased in LPS+ Xuebijing group and LPS+ paeoniflorin group. Compared with that in blank control group, the apoptosis rate of CD4(+) CD25(+) Tregs in simple LPS group was significantly declined (t=6.02, P<0.01). Compared with the rate in simple LPS group, the apoptosis rates of CD4(+) CD25(+) Tregs in LPS+ Xuebijing group and LPS+ paeoniflorin group were significantly increased (t=20.32, 8.60, P<0.01). (2) Compared with those in simple CD3/CD28' group, the proliferative rate of CD4(+) T cells was significantly decreased in simple LPS' group (t=22.47, P<0.01), while IL-4 level from culture supernatant was significantly elevated (t=3.51, P<0.01). Compared with those in simple LPS' group, the proliferative rates of CD4(+) T cells in LPS+ Xuebijing' group and LPS+ paeoniflorin' group were significantly increased (t=16.31, 11.48, P<0.01), while IL-4 level from culture supernatant showed no obvious change. (3) The post-operative 7-day survival rates of rats in sham surgery group, simple sepsis group, sepsis+ Xuebijing group, sepsis+ paeoniflorin group were 100% (30/30), 30% (9/30), 57% (17/30), and 47% (14/30), respectively. Compared with that in simple sepsis group, the survival rate within post-operative 7-day of rats in sepsis+ Xuebijing group was significantly higher (χ(2)=4.34, P<0.05), while the survival rate within post-operative 7-day of rats in sepsis+ paeoniflorin group showed no obvious change. Conclusions: Both Xuebijing and its component paeoniflorin are capable of reversing sepsis-induced inhibitory immune function and apoptotic resistant of Tregs in rats, and further improving the proliferative activity of T cells. In addition, the effect of paeoniflorin on improvement of survival rate of rats with sepsis is weaker than Xuebijing.

Thymosin α1 therapy in critically ill patients with COVID-19: A multicenter retrospective cohort study

•

Thymosin α1can markedly decrease 28-day mortality (HR, 0.11, 95% CI 0.02–0.63, P = 0.013) and attenuate acute lung injury (P = 0.036) in critical type COVID-19 patients.

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Thymosin α1 can markedly prolonged the hospital length of stay (P = 0.024) as well as the total duration of the disease (P = 0.001) in the critical type COVID-19 patients.

Background

COVID-19 characterized by refractory hypoxemia increases patient mortality because of immunosuppression effects. This study aimed to evaluate the efficacy of immunomodulatory with thymosin α1 for critical COVID-19 patients.

Methods

This multicenter retrospective cohort study was performed in 8 government-designated treatment centers for COVID-19 patients in China from Dec. 2019 to Mar. 2020. Thymosin α1 was administrated with 1.6 mg qd or q12 h for >5 days. The primary outcomes were the 28-day and 60-day mortality, the secondary outcomes were hospital length of stay and the total duration of the disease. Subgroup analysis was carried out according to clinical classification.

Results

Of the 334 enrolled COVID-19 patients, 42 (12.6%) died within 28 days, and 55 (16.5%) died within 60 days of hospitalization. There was a significant difference in the 28-day mortality between the thymosin α1 and non-thymosin α1-treated groups in adjusted model (P = 0.016), without obvious differences in the 60-day mortality and survival time in the overall cohort (P > 0.05). In the subgroup analysis, it was found that thymosin α1 therapy significantly reduced 28-day mortality (Hazards Ratios HR, 0.11, 95% confidence interval CI 0.02–0.63, P=0.013) via improvement of Pa0₂/FiO₂ (P = 0.036) and prolonged the hospital length of stay (P = 0.024) as well as the total duration of the disease (P=0.001) in the critical type patients, especially those aged over 64 years, with white blood cell >6.8×10⁹/L, neutrophil >5.3×10⁹/L, lymphocyte < 0.73 × 10⁹/L, PaO₂/FiO₂ < 196, SOFA > 3, and acute physiology and chronic health evaluation (APACHE) II > 7.

Conclusion

These results suggest that treatment with thymosin α1 can markedly decrease 28-day mortality and attenuate acute lung injury in critical type COVID-19 patients.

Comparison of clinical laboratory tests between bacterial sepsis and SARS-CoV-2-associated viral sepsis

Sepsis is a life-threatening condition that is characterized by multiple organ dysfunction due to abnormal host response to various pathogens, like bacteria, fungi and virus. The differences between viral and bacterial sepsis are indeed of great significance to deepen the understanding of the pathogenesis of sepsis, especially under pandemics of SARS-CoV-2 infection.

Biology of Interleukin-17 and Its Pathophysiological Significance in Sepsis

The interleukin (IL)-17 family includes six structure-related cytokines (A-F). To date, majority of studies have focused on IL-17A. IL-17A plays a pivotal role in various infectious diseases, inflammatory and autoimmune disorders, and cancer. Several recent studies have indicated that IL-17A is a biomarker as well as a therapeutic target in sepsis. In the current review, we summarize the biological functions of IL-17, including IL-17-mediated responses and signal transduction pathways, with particular emphasis on clinical relevance to sepsis.

Autocrine Regulation of Interleukin-3 in the Activity of Regulatory T Cells and its Effectiveness in the Pathophysiology of Sepsis

Regulatory T cells (Tregs) play a crucial role in modulating the inflammatory response and participated in sepsis-related immune dysfunctions. However, little is known about the regulatory mechanisms by which Tregs are kept in check during immune responses. Here, we verified the simultaneous expression of interleukin-3 (IL-3) and its receptor (IL-3R) in Tregs. Then, by modulation of IL-3 expression via lentiviral transduction-mediated small interfering RNA, we demonstrated that IL-3 negatively regulated Tregs activity via an autocrine mechanism. Furthermore, we found that anti-IL-3 antibody treatment significantly diminished inflammatory cytokines and organ injury, and improved survival in septic mice, which was associated with enhanced Treg percentage and function. Collectively, these results suggest that IL-3 negatively regulates the activity of Tregs in a previously unrecognized autocrine manner, and plays an important role in the excessive inflammatory response in sepsis, which might be utilized as a therapeutic strategy for the treatment of complications in sepsis.

[Survival time and related factors on HIV/AIDS patients in Guizhou province from 1995 to 2018]

Objective: To examine the survival time and related factors on HIV/AIDS patients in Guizhou province from 1995 to 2018. Methods: A retrospective cohort study was conducted to analyze the HIV/AIDS case from 1995 to 2018 in Guizhou province with data gathered from the "Chinese National Comprehensive HIV/AIDS Prevention and care Information system". Survival rate was calculated by life table and survival time was estimated by Kaplan-Meier. Related factors on survival time were analyzed by Cox regression model. Results: A total of 53 232 HIV/AIDS cases were included in the study, with the mortality rate as 8.53/100 person-years (14 210/166 679.18), median survival time as 10.20 (95%CI: 9.91-10.48) years, and survival rates of 1, 5, 10 and 20 years as 0.85, 0.68, 0.51, 0.36, 0.19 respectively. Results from the multivariate Cox regression analysis showed that factors as: being male (compared with females, aHR=0.757, 95%CI: 0.727-0.788), with antiviral treatment (ART) (compared with those without ART, aHR=0.173, 95%CI: 0.165-0.181), CD(4)<200 cells/μl[compared with CD(4)(+)T cells (CD(4)) ≥200 cells/μl, aHR=0.410, 95%CI: 0.387-0.435], age ≥45 (compared with age<45, aHR=1.506, 95%CI: 1.193-1.901), illiterate (compared with having high school education or above, aHR=0.904, 95%CI: 0.832-0.982), unmarried (compared with divorced or widowed, aHR=0.896, 95%CI: 0.848-0.946), through heterosexual transmission (compared with homosexual transmission, aHR=0.555, 95%CI: 0.487-0.632), ethnic minorities (compared with Hans, aHR=1.185, 95%CI: 1.114-1.262), and farmers/migrant workers (compared with domestic/unemployed,aHR=0.874, 95%CI: 0.834-0.916,) etc., were related to the survival time of HIV/AIDS, in Guizhou province. Conclusions: The mortality rate of HIV/AIDS in Guizhou province appeared relatively high, but with no obvious downward trend seen in the last years. Factors as being male, age ≥45, low education level, ethnic minorities, CD(4)<200 cells/μl were identified as related to the HIV/AIDS survival time. We would suggest that treatment and follow-up management programs should be strengthened to improve the quality of life among these patients.

Effect of TIPE1 on Immune Function of Dendritic Cells and Its Signaling Pathway in Septic Mice

Dendritic cell (DC) dysfunction plays a pivotal role in sepsis-induced immunosuppression. Tumor necrosis factor α (TNF-α)-induced protein 8 like-1 (TIPE1), a new member of the tumor necrosis factor α-induced protein 8 family, may be related to cell death. The aim of the present study was to elucidate the effect of TIPE1 on the immune function of DCs and its regulatory mechanism via PD-L1/PD-1 signaling in mice. Sepsis was induced in adult C57BL/6 male mice via cecal ligation and puncture. In vitro, we found that expression of CD80, CD86, and major histocompatibility complex class II in DCs and levels of cytokines, including tumor necrosis factor α and interleukin 12p40, were elevated; similarly, T-cell proliferation and differentiation were promoted when the gene expressing TIPE1 was silenced. Next, we examined the in vivo role of TIPE1 in a cecal ligation and puncture animal model system. Flow cytometry of the immune functional status in DCs revealed negative regulation of TIPE1 on DC maturation, as well as activation. Moreover, changes in PD-L1/PD-1 levels confirmed the negative effect of TIPE1 in DCs. Collectively, we report that TIPE1 might exert negative regulation in sepsis, at least in part by inhibiting DC maturation and subsequent T-cell-mediated immunity via PD-L1/PD-1 signaling.

Plasma glucagon-like peptide 1 was associated with hospital-acquired infections and long-term mortality in burn patients

BACKGROUND

Although glucagon-like peptide 1 levels have been closely associated with inflammation and mortality in septic patients, the clinical importance of glucagon-like peptide 1 on hospital-acquired infections and long-term mortality after burn injury remains unexplored.

METHODS

Plasma samples from 144 burn patients were collected on admission to determine total glucagon-like peptide 1, interleukin 6, and monocyte chemotactic protein-1 levels. Hospital-acquired infections were determined by positive microbial culture. One-year mortality was assessed by telephone interview. Factors associated with glucagon-like peptide 1 were determined by multivariable linear logistic regression. Predicting the clinical importance of glucagon-like peptide 1 on the development of hospital-acquired infections and mortality were determined by Cox proportional hazards models and further by receiver operating characteristic curve analysis. Kaplan-Meier analyses were performed to examine whether the mean glucagon-like peptide 1 level of the cohort could discriminate the hospital-acquired infections-free survival.

RESULTS

Median burn size was 41% (19%-70%) of total body surface area. Hospital-acquired infections developed in 36 (25%) patients after a mean of 10 ± 1 days after injury. Interleukin 6, monocyte chemotactic protein-1, and blood urea nitrogen levels and thrombin time were independently associated with increased glucagon-like peptide 1 levels. Levels of glucagon-like peptide 1 (median, interquartile range) were greater in patients who developed hospital-acquired infections than in those who did not (237 pmol/L, 76-524 vs 80 pmol/L, 51-158; P < .001) and in patients who died (536 pmol/L, interquartile range: 336-891 pmol vs 98 pmol/L, 47-189; P < .001). Although the glucagon-like peptide 1 level could not predict hospital-acquired infections-free survival in individual patients, it could predict 1-year mortality independently (P = .021). Moreover, a glucagon-like peptide 1 level of 200 pmol/L could discriminate hospital-acquired infections-free survival (P < .001).

CONCLUSION

Admission glucagon-like peptide 1 level can discriminate hospital-acquired infections-free survival and predict long-term mortality in a group of patients with burn injury. Our data suggests that glucagon-like peptide 1 may be a predictive biomarker for hospital-acquired infections and mortality in burn patients.

Association between furosemide administration and outcomes in critically ill patients with acute kidney injury

Background

Although current guidelines for AKI suggested against the use of furosemide in AKI management, the effect of furosemide on outcomes in real-world clinical settings remains uncertain. The aim of the present study was to investigate the association between furosemide administration and outcomes in critically ill patients with AKI using real-world data.

Methods

Critically ill patients with AKI were identified from the Medical Information Mart for Intensive Care (MIMIC)-III database. Propensity score (PS) matched analysis was used to match patients receiving furosemide to those without diuretics treatment. Linear regression, logistic regression model, and Cox proportional hazards model were used to assess the associations between furosemide and length of stay, recovery of renal function, and in-hospital and 90-day mortality, respectively.

Results

A total of 14,154 AKI patients were included in the data analysis. After PS matching, 4427 pairs of patients were matched between the patients who received furosemide and those without diuretics treatment. Furosemide was associated with reduced in-hospital mortality [hazard ratio (HR) 0.67; 95% CI 0.61–0.74; P < 0.001] and 90-day mortality [HR 0.69; 95% CI 0.64–0.75; P < 0.001], and it was also associated with the recovery of renal function [HR 1.44; 95% CI 1.31–1.57; P < 0.001] in over-all AKI patients. Nevertheless, results illustrated that furosemide was not associated with reduced in-hospital mortality in patients with AKI stage 0–1 defined by UO criteria, AKI stage 2–3 according to SCr criteria, and in those with acute-on-chronic (A-on-C) renal injury.

Conclusions

Furosemide administration was associated with improved short-term survival and recovery of renal function in critically ill patients with AKI. Furosemide was especially effective in patients with AKI UO stage 2–3 degree. However, it was not effective in those with AKI SCr stage 2–3 and chronic kidney disease. The results need to be verified in randomized controlled trials.

[Advances in the research of the relationship between skin regulatory T cells and wound healing and immune diseases]

As the body's largest organ, skin harbors a large amount of immune cells to regulate both innate and adaptive immune responses. Regulatory T cells (Tregs), as a subset of T lymphocytes with negative regulatory functions, play an important role in maintaining the immune homeostasis of different tissue. However, researches of skin Tregs are largely limited and uncompleted as compared with other tissue. In recent years, a comprehensive understanding is increasingly showing the specialized functions of Tregs in skin, including the orchestration of tissue wound healing, involvement in hair follicle recycling, and modulation of proper immune homeostasis. In this review, we outline the classification and characteristics of Tregs in skin, distribution, migration routes, immune effects, and relationship with wound healing, which aims to deepening our understanding towards the immunological effects of T lymphocytes subsets in skin and its regulatory pathways.

[Update in immune regulatory dysfunction of dendritic cells in sepsis]

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. Further development of sepsis usually leads to septic shock or even death. Many previous studies have focused on the abnormal reactions of monocytes/macrophages, neutrophils, complement system, or cytokine inflammation in sepsis. Many evidences in recent years suggest that dendritic cells, as the most powerful antigen-presenting cells in innate immune system of body, play important role during the process of immune disorders of sepsis. In this article, I review the main classification, immune function, monitoring method, regulatory pathways of dendritic cells and their clinical significance in immune disorders of sepsis, so as to find new strategies for immune regulation of sepsis.

Sestrin2 protects dendritic cells against endoplasmic reticulum stress-related apoptosis induced by high mobility group box-1 protein

Sestrin2 (SESN2) is a highly evolutionary conserved protein and involved in different cellular responses to various stresses. However, the potential function of SESN2 in immune system remains unclear. The present study was designed to test whether dendritic cells (DCs) could express SESN2, and investigate the underlying molecular mechanism as well as its potential significance. Herein, we firstly reported that SESN2 was expressed in DCs after high mobility group box-1 protein (HMGB1) stimulation and the apoptosis of DCs was obviously increased when SESN2 gene silenced by siRNA. Cells undergone SESN2-knockdown promoted endoplasmic reticulum (ER) stress (ERS)-related cell death, markedly exacerbated ER disruption as well as the formation of dilated and aggregated structures, and they significantly aggravated the extent of ERS response. Conversely, overexpressing SESN2 DCs markedly decreased apoptotic rates and attenuated HMGB1-induced ER morphology fragment together with inhibition of ERS-related protein translation. Furthermore, sesn2^−/−-deficient mice manifested increased DC apoptosis and aggravated ERS extent in septic model. These results indicate that SESN2 appears to be a potential regulator to inhibit apoptotic ERS signaling that exerts a protective effect on apoptosis of DCs in the setting of septic challenge.

Organelle-specific autophagy in inflammatory diseases: a potential therapeutic target underlying the quality control of multiple organelles

The structural integrity and functional stability of organelles are prerequisites for the viability and responsiveness of cells. Dysfunction of multiple organelles is critically involved in the pathogenesis and progression of various diseases, such as chronic obstructive pulmonary disease, cardiovascular diseases, infection, and neurodegenerative diseases. In fact, those organelles synchronously present with evident structural derangement and aberrant function under exposure to different stimuli, which might accelerate the corruption of cells. Therefore, the quality control of multiple organelles is of great importance in maintaining the survival and function of cells and could be a potential therapeutic target for human diseases. Organelle-specific autophagy is one of the major subtypes of autophagy, selectively targeting different organelles for quality control. This type of autophagy includes mitophagy, pexophagy, reticulophagy (endoplasmic reticulum), ribophagy, lysophagy, and nucleophagy. These kinds of organelle-specific autophagy are reported to be beneficial for inflammatory disorders by eliminating damaged organelles and maintaining homeostasis. In this review, we summarized the recent findings and mechanisms covering different kinds of organelle-specific autophagy, as well as their involvement in various diseases, aiming to arouse concern about the significance of the quality control of multiple organelles in the treatment of inflammatory diseases.Abbreviations: ABCD3: ATP binding cassette subfamily D member 3; AD: Alzheimer disease; ALS: amyotrophic lateral sclerosis; AMBRA1: autophagy and beclin 1 regulator 1; AMPK: AMP-activated protein kinase; ARIH1: ariadne RBR E3 ubiquitin protein ligase 1; ATF: activating transcription factor; ATG: autophagy related; ATM: ATM serine/threonine kinase; BCL2: BCL2 apoptosis regulator; BCL2L11/BIM: BCL2 like 11; BCL2L13: BCL2 like 13; BECN1: beclin 1; BNIP3: BCL2 interacting protein 3; BNIP3L/NIX: BCL2 interacting protein 3 like; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2; CANX: calnexin; CAT: catalase; CCPG1: cell cycle progression 1; CHDH: choline dehydrogenase; COPD: chronic obstructive pulmonary disease; CSE: cigarette smoke exposure; CTSD: cathepsin D; DDIT3/CHOP: DNA-damage inducible transcript 3; DISC1: DISC1 scaffold protein; DNM1L/DRP1: dynamin 1 like; EIF2AK3/PERK: eukaryotic translation initiation factor 2 alpha kinase 3; EIF2S1/eIF2α: eukaryotic translation initiation factor 2 alpha kinase 3; EMD: emerin; EPAS1/HIF-2α: endothelial PAS domain protein 1; ER: endoplasmic reticulum; ERAD: ER-associated degradation; ERN1/IRE1α: endoplasmic reticulum to nucleus signaling 1; FBXO27: F-box protein 27; FKBP8: FKBP prolyl isomerase 8; FTD: frontotemporal dementia; FUNDC1: FUN14 domain containing 1; G3BP1: G3BP stress granule assembly factor 1; GBA: glucocerebrosidase beta; HIF1A/HIF1: hypoxia inducible factor 1 subunit alpha; IMM: inner mitochondrial membrane; LCLAT1/ALCAT1: lysocardiolipin acyltransferase 1; LGALS3/Gal3: galectin 3; LIR: LC3-interacting region; LMNA: lamin A/C; LMNB1: lamin B1; LPS: lipopolysaccharide; MAPK8/JNK: mitogen-activated protein kinase 8; MAMs: mitochondria-associated membranes; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; MFN1: mitofusin 1; MOD: multiple organelles dysfunction; MTPAP: mitochondrial poly(A) polymerase; MUL1: mitochondrial E3 ubiquitin protein ligase 1; NBR1: NBR1 autophagy cargo receptor; NLRP3: NLR family pyrin domain containing 3; NUFIP1: nuclear FMR1 interacting protein 1; OMM: outer mitochondrial membrane; OPTN: optineurin; PD: Parkinson disease; PARL: presenilin associated rhomboid like; PEX3: peroxisomal biogenesis factor 3; PGAM5: PGAM family member 5; PHB2: prohibitin 2; PINK1: PTEN induced putative kinase 1; PRKN: parkin RBR E3 ubiquitin protein ligase; RB1CC1/FIP200: RB1 inducible coiled-coil 1; RETREG1/FAM134B: reticulophagy regulator 1; RHOT1/MIRO1: ras homolog family member T1; RIPK3/RIP3: receptor interacting serine/threonine kinase 3; ROS: reactive oxygen species; RTN3: reticulon 3; SEC62: SEC62 homolog, preprotein translocation factor; SESN2: sestrin2; SIAH1: siah E3 ubiquitin protein ligase 1; SNCA: synuclein alpha; SNCAIP: synuclein alpha interacting protein; SQSTM1/p62: sequestosome 1; STING1: stimulator of interferon response cGAMP interactor 1; TAX1BP1: Tax1 binding protein 1; TBK1: TANK binding kinase 1; TFEB: transcription factor EB; TICAM1/TRIF: toll-like receptor adaptor molecule 1; TIMM23: translocase of inner mitochondrial membrane 23; TNKS: tankyrase; TOMM: translocase of the outer mitochondrial membrane; TRIM: tripartite motif containing; UCP2: uncoupling protein 2; ULK1: unc-51 like autophagy activating kinase; UPR: unfolded protein response; USP10: ubiquitin specific peptidase 10; VCP/p97: valosin containing protein; VDAC: voltage dependent anion channels; XIAP: X-linked inhibitor of apoptosis; ZNHIT3: zinc finger HIT-type containing 3.

Is haemoglobin below 7.0 g/dL an optimal trigger for allogenic red blood cell transfusion in patients admitted to intensive care units? A meta-analysis and systematic review

OBJECTIVES

We employed a comprehensive systematic review and meta-analysis to assess benefits and risks of a threshold of haemoglobin level below 7 g/dL versus liberal transfusion strategy among critically ill patients, and even patients with septic shock.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

We performed systematical searches for relevant randomised controlled trials (RCTs) in the Cochrane Library, EMBASE and PubMed databases up to 1 September 2019.

ELIGIBILITY CRITERIA

RCTs among adult intensive care unit (ICU) patients comparing 7 g/dL as restrictive strategy with liberal transfusion were incorporated.

DATA EXTRACTION AND SYNTHESIS

The clinical outcomes, including short-term mortality, length of hospital stay, length of ICU stay, myocardial infarction (MI) and ischaemic events, were screened and analysed after data collection. We applied odds ratios (ORs) to analyse dichotomous outcomes and standardised mean differences (SMDs) to analyse continuous outcomes with fixed or random effects models based on heterogeneity evaluation for each outcome.

RESULTS

Eight RCTs with 3415 patients were included. Compared with a more liberal threshold, a red blood cell (RBC) transfusion threshold <7 g/dL haemoglobin showed no significant difference in short-term mortality (OR: 0.90, 95% CI: 0.67 to 1.21, p=0.48, I²=53%), length of hospital stay (SMD: -0.11, 95% CI: -0.30 to 0.07, p=0.24, I²=71%), length of ICU stay (SMD: -0.03, 95% CI: -0.14 to 0.08, p=0.54, I²=0%) or ischaemic events (OR: 0.80, 95% CI: 0.43 to 1.48, p=0.48, I²=51%). However, we found that the incidence of MI (OR: 0.54, 95% CI: 0.30 to 0.98, p=0.04, I²=0%) was lower in the group with the threshold <7 g/dL than that with the more liberal threshold.

CONCLUSIONS

An RBC transfusion threshold <7 g/dL haemoglobin is incapable of decreasing short-term mortality in ICU patients according to currently published evidences, while it might have potential role in reducing MI incidence.

Sepsis-associated encephalopathy: a vicious cycle of immunosuppression

Sepsis-associated encephalopathy (SAE) is commonly complicated by septic conditions, and is responsible for increased mortality and poor outcomes in septic patients. Uncontrolled neuroinflammation and ischemic injury are major contributors to brain dysfunction, which arises from intractable immune malfunction and the collapse of neuroendocrine immune networks, such as the cholinergic anti-inflammatory pathway, hypothalamic-pituitary-adrenal axis, and sympathetic nervous system. Dysfunction in these neuromodulatory mechanisms compromised by SAE jeopardizes systemic immune responses, including those of neutrophils, macrophages/monocytes, dendritic cells, and T lymphocytes, which ultimately results in a vicious cycle between brain injury and a progressively aberrant immune response. Deep insight into the crosstalk between SAE and peripheral immunity is of great importance in extending the knowledge of the pathogenesis and development of sepsis-induced immunosuppression, as well as in exploring its effective remedies.