Leukocytes, Systemic Inflammation and Immunopathology in Acute-on-Chronic Liver Failure

Hematological ratios in patients with acute decompensation and acute-on-chronic liver failure: prognostic factors

BACKGROUND AND AIMS

Acute-on-chronic liver failure (ACLF) is the most severe form of acutely decompensated cirrhosis and is characterized by the presence of intense systemic inflammation. Leucocyte quantification can serve as an indirect indicator of systemic inflammation. In our study, we investigated the predictive value of hematological ratios (neutrophils to lymphocytes, monocyte to lymphocytes, platelets to lymphocytes, lymphocytes to C-reactive protein, and neutrophils to lymphocytes and platelets) in acute decompensation (AD) and ACLF patients and their relation to disease severity and early mortality.

PATIENTS AND METHODS

We included 60 patients with ACLF and AD, and 30 cirrhotic controls. Clinical data were collected, and survival was followed for 1 and 6 months. Blood samples were analyzed at admission for differential leucocytes and assessed for liver and renal function tests. The leukocyte ratios were calculated and compared, and their correlation with liver function indicators and prognosis was assessed.

RESULTS

All ratios were significantly higher in AD and ACLF patients compared to control (except for lymphocyte to C-reactive protein ratio which was significantly lower), and were positively correlated with Child-Pugh score, model for end-stage liver disease (MELD)-Na, and ACLF severity scores. Multivariate regression revealed that neutrophil to lymphocyte ratio, monocyte to lymphocyte ratio, and MELD-Na were independent prognostic factors of 1-month and 6-month mortality. A unique prognostic nomogram incorporating MELD-Na, neutrophil to lymphocyte ratio, and monocyte to lymphocyte ratio could be proposed for predicting prognosis in AD and ACLF patients.

CONCLUSIONS

Cheap, easy, and noninvasive hematological ratios are introduced as a tool for early identification and risk stratification of AD and ACLF patients.

Chishao - Fuzi herbal pair restore the macrophage M1/M2 balance in acute-on-chronic liver failure

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional herbal pair Paeoniae Radix Rubra (roots of Paeonia lactiflora Pall., Chishao in Chinese) and Aconiti Lateralis Radix Praeparata (lateral roots of Aconitum carmichaelii Debeaux, Fuzi in Chinese) are widely used for the treatment of liver diseases, demonstrating clinical efficacy against acute-on-chronic liver failure (ACLF). As the core drug pair representing the "clearing method" and "warming method" in traditional Chinese medicine (TCM), they align with the TCM syndromic characteristics of ACLF, characterized by a mixture of deficiencies and realities. However, the molecular mechanisms underlying the anti-ACLF effects of Chishao - Fuzi herbal pair remain unclear.

AIM OF THE STUDY

To reveal the immunoinflammatory status of patients with hepatitis B virus-related ACLF (HBV-ACLF) based on macrophage polarization and to explore the mechanism of action of Chishao - Fuzi herbal pair in regulating macrophage polarization against ACLF.

MATERIALS AND METHODS

Peripheral blood samples were prospectively obtained from patients with HBV-ACLF, patients with chronic hepatitis B (CHB) in the immunoactive phase and healthy individuals. Flow cytometry, qRT-qPCR, and ELISA were used to reveal the activation status of monocyte-macrophages and the expression differences in related cytokines in the peripheral blood of patients with HBV-ACLF. Then, an ACLF rat model and a macrophage inflammation model in vitro were established. Hematoxylin-eosin staining, immunohistochemical staining, transmission electron microscopy, flow cytometry, western blotting, RT-qPCR, and ELISA were used to observe changes in the expression of M1/M2 macrophage markers and related inflammatory factors after Chishao - Fuzi herbal pair intervention, both in vivo and in vitro.

RESULTS

Patients with HBV-ACLF exhibited an imbalance in M1/M2 macrophage polarization, showing a tendency to activate M1 macrophages with high expression of CD86 and iNOS. This imbalance led to an increase in relevant pro-inflammatory factors (IL-1β, IL-6, TNF-α) and a decrease in anti-inflammatory factors (IL-10, TGF-β, VEGF), exacerbating the uncontrolled immune-inflammatory response. Chishao - Fuzi herbal pair intervention improved liver function, coagulation function, and histopathological injury in ACLF rats. It also partially ameliorated endotoxemia and inflammatory injury in ACLF. The mechanism was to restore the immune-inflammatory imbalance and prevent the exacerbation of inflammatory response to liver failure by promoting macrophage polarization toward M2 anti-inflammatory direction, inhibiting M1 macrophage activation, and increasing the levels of anti-inflammatory factors and decreasing pro-inflammatory factors.

CONCLUSION

Chishao - Fuzi herbal pair can reduce the systemic inflammatory burden of liver failure by modulating macrophage polarization and restoring ACLF immune-inflammatory imbalance. This study provides new perspectives and strategies for studying HBV-ACLF immune reconstitution and inflammatory response control.

Expert consensus on the diagnosis and treatment of end-stage liver disease complicated by infections

End-stage liver disease (ESLD) is a life-threatening clinical syndrome and when complicated with infection the mortality is markedly increased. In patients with ESLD, bacterial or fungal infection can induce or aggravate the occurrence or progression of liver decompensation. Consequently, infections are among the most common complications of disease deterioration. There is an overwhelming need for standardized protocols for early diagnosis and appropriate management for patients with ESLD complicated by infections. Asia Pacific region has the largest number of ESLD patients, due to hepatitis B and the growing population of alcohol and NAFLD. Concomitant infections not only add to organ failure and high mortality but also to financial and healthcare burdens. This consensus document assembled up-to-date knowledge and experience from colleagues across the Asia-Pacific region, providing data on the principles as well as evidence-based current working protocols and practices for the diagnosis and treatment of patients with ESLD complicated by infections.

Circulating bacterial peptides and linked metabolomic signatures are indicative of early mortality in pediatric cirrhosis

BACKGROUND

Patients with pediatric cirrhosis-sepsis (PC-S) attain early mortality. Plasma bacterial composition, the cognate metabolites, and their contribution to the deterioration of patients with PC-S to early mortality are unknown. We aimed to delineate the plasma metaproteome-metabolome landscape and identify molecular indicators capable of segregating patients with PC-S predisposed to early mortality in plasma, and we further validated the selected metabolite panel in paired 1-drop blood samples using untargeted metaproteomics-metabolomics by UHPLC-HRMS followed by validation using machine-learning algorithms.

METHODS

We enrolled 160 patients with liver diseases (cirrhosis-sepsis/nonsepsis [n=110] and noncirrhosis [n=50]) and performed untargeted metaproteomics-metabolomics on a training cohort of 110 patients (Cirrhosis-Sepsis/Nonsepsis, n=70 and noncirrhosis, n=40). The candidate predictors were validated on 2 test cohorts-T1 (plasma test cohort) and T2 (1-drop blood test cohort). Both T1 and T2 had 120 patients each, of which 70 were from the training cohort.

RESULTS

Increased levels of tryptophan metabolites and Salmonella enterica and Escherichia coli-associated peptides segregated patients with cirrhosis. Increased levels of deoxyribose-1-phosphate, N5-citryl-d-ornithine, and Herbinix hemicellulolytic and Leifsonia xyli segregated patients with PC-S. MMCN-based integration analysis of WMCNA-WMpCNA identified key microbial-metabolic modules linked to PC-S nonsurvivors. Increased Indican, Staphylobillin, glucose-6-phosphate, 2-octenoylcarnitine, palmitic acid, and guanidoacetic acid along with L. xyli, Mycoplasma genitalium, and Hungateiclostridium thermocellum segregated PC-S nonsurvivors and superseded the liver disease severity indices with high accuracy, sensitivity, and specificity for mortality prediction using random forest machine-learning algorithm.

CONCLUSIONS

Our study reveals a novel metabolite signature panel capable of segregating patients with PC-S predisposed to early mortality using as low as 1-drop blood.

Development and validation of a predictive model for acute-on-chronic liver failure after transjugular intrahepatic portosystemic shunt

BACKGROUND

Transjugular intrahepatic portosystemic shunt (TIPS) is a cause of acute-on-chronic liver failure (ACLF).

AIM

To investigate the risk factors of ACLF within 1 year after TIPS in patients with cirrhosis and construct a prediction model.

METHODS

In total, 379 patients with decompensated cirrhosis treated with TIPS at Nanjing Drum Tower Hospital from 2017 to 2020 were selected as the training cohort, and 123 patients from Nanfang Hospital were included in the external validation cohort. Univariate and multivariate logistic regression analyses were performed to identify independent predictors. The prediction model was established based on the Akaike information criterion. Internal and external validation were conducted to assess the performance of the model.

RESULTS

Age and total bilirubin (TBil) were independent risk factors for the incidence of ACLF within 1 year after TIPS. We developed a prediction model comprising age, TBil, and serum sodium, which demonstrated good discrimination and calibration in both the training cohort and the external validation cohort.

CONCLUSION

Age and TBil are independent risk factors for the incidence of ACLF within 1 year after TIPS in patients with decompensated cirrhosis. Our model showed satisfying predictive value.

Assessment of the Risk of Malnutrition or Frailty Among Patients Undergoing Liver Transplantation: A Hospital-Based Prospective Study

Objective

We aimed to explore the status of nutritional and frailty in patients undergoing liver transplantation and the associated influencing factors.

Methods

We conducted a follow-up analysis of 44 patients who underwent liver transplantation between 2021 and 2022. We followed up and recorded the nutritional status and risk of weakness at different time-points (days 1, 2, 3, 6, 9, and 12) postoperatively. Patient information regarding demographics, physical examination, medical history, and perioperative blood tests were collected. Binary logistic regression was applied to identify risk factors for weakness after liver transplantation.

Results

The cohort comprised 44 liver transplant recipients, with a mean age of 47.66 years (standard deviation=9.49 years). Initial analysis revealed that, compared to the group without nutritional risks, the group with nutritional risks displayed elevated age and preoperative blood ammonia levels one week post-surgery. Moreover, this group had reduced levels of albumin and total bile acid preoperatively. Patients with preoperative nutritional risks were also prone to similar risks 2 weeks postoperatively. Further, a correlation was observed between preoperative pulmonary infections and increased frailty risk 6 days postoperatively. At both 9 and 12 days postoperatively, patients with frailty risk exhibited higher preoperative white blood cell counts and ammonia levels than those without. Multivariable analysis, controlling for confounding factors, indicated a significant association between preoperative nutritional status and nutritional risk 2 weeks postoperatively, as well as a link between preoperative white blood cell count and frailty risk at 12 days postoperatively.

Conclusion

There was a significant correlation between preoperative nutritional status and nutritional risk 2 weeks after liver transplantation, and preoperative white blood cell count was an independent risk factor for weakness 12 days postoperatively. Preoperative nutritional management for patients could potentially mitigate the likelihood of adverse clinical outcomes.

Immunopathogenesis of acute on chronic liver failure

Acute-on-chronic liver failure is a well-established description of a high-mortality syndrome of chronic liver disease (usually cirrhosis) with organ failure. While the exact definition is under refinement, the accepted understanding of this entity is in patients with chronic liver disease and various organs in failure and where systemic inflammation is a major component of the pathobiology. There are limited therapies for a disease with such a poor prognosis, and while improvements in the critical care management and for very few patients, liver transplantation, mean 50% can survive to hospital discharge, rapid application of new therapies is required. Here we explain the current understanding of the immunologic abnormalities seen in acute-on-chronic liver failure across the innate and adaptive immune systems, the role of the hepatic cell death and the gut-liver axis, and recommendations for future research and treatment paradigms.

Acute non-traffic traumatic spinal cord injury in the aging population: Analysis of the National Inpatient Sample 2005-2018

BACKGROUND

This study aimed to determine risk factors for poor in-hospital outcomes in a large cohort of older adult patients with acute non-traffic traumatic spinal cord injury (tSCI).

METHODS

This is a population-based, retrospective, observational study. Data of older adults ≥65 years with a primary discharge diagnosis of acute non-traffic tSCI were extracted from the US National Inpatient Sample (NIS) database 2005-2018. Traffic-related tSCI admissions or patients lacking complete data on age, sex and outcomes of interest were excluded. Univariate and multivariate logistic regression analysis was used to determine associations between variables and in-hospital outcomes.

RESULTS

Data of 49,449 older patients (representing 246,939 persons in the US) were analyzed. The mean age was 79.9 years. Multivariable analyses revealed that severe International Classification of Disease (ICD)-based injury severity score (ICISS) (adjusted odds ratio [aOR] = 3.14, 95% confidence interval [CI]: 2.77-3.57), quadriplegia (aOR = 2.79, 95%CI: 2.34-3.32), paraplegia (aOR = 2.60, 95%CI:1.89-3.58), cervical injury with vertebral fracture (aOR = 2.19, 95%CI: 1.90-2.52), and severe liver disease (aOR = 2.33, 95%CI: 1.34-4.04) were all strong independent predictors of in-hospital mortality. In addition, malnutrition (aOR = 3.19, 95% CI: 2.93-3.48) was the strongest predictors of prolonged length of stay (LOS).

CONCLUSIONS

Several critical factors for in-hospital mortality, unfavorable discharge, and prolonged LOS among US older adults with acute non-traffic tSCI were identified. In addition to the factors associated with initial severity, the presence of severe liver disease and malnutrition emerged as strong predictors of unfavorable outcomes, highlighting the need for special attention for these patient subgroups.

Interleukins in liver disease treatment

Cytokines play pleiotropic roles in human health and disease by regulating both innate and adaptive immune responses. Interleukins (ILs), a large group of cytokines, can be divided into seven families, including IL-1, IL-2, IL-6, IL-8, IL-10, IL-12, and IL-17 families. Here, we review the functions of ILs in the pathogenesis and resolution of liver diseases, such as liver inflammation (e.g., IL-35), alcohol-related liver disease (e.g., IL-11), non-alcoholic steatohepatitis (e.g., IL-22), liver fibrosis (e.g., Il-17a), and liver cancer (e.g., IL-8). Overall, IL-1 family members are implicated in liver inflammation induced by different etiologies, such as alcohol consumption, high-fat diet, and hepatitis viruses. IL-2 family members mainly regulate T lymphocyte and NK cell proliferation and activation, and the differentiation of T cells. IL-6 family cytokines play important roles in acute phase response in liver infection, liver regeneration, and metabolic regulation, as well as lymphocyte activation. IL-8, also known as CXCL8, is activated in chronic liver diseases, which is associated with the accumulation of neutrophils and macrophages. IL-10 family members contribute key roles to liver immune tolerance and immunosuppression in liver disease. IL-12 family cytokines influence T-cell differentiation and play an essential role in autoimmune liver disease. IL-17 subfamilies contribute to infection defense, liver inflammation, and Th17 cell differentiation. ILs interact with different type I and type II cytokine receptors to regulate intracellular signaling pathways that mediate their functions. However, most clinical studies are only performed to evaluate IL-mediated therapies on alcohol and hepatitis virus infection-induced hepatitis. More pre-clinical and clinical studies are required to evaluate IL-mediated monotherapy and synergistic therapies.

Increased IgA-mediated responses to the gut paracellular pathway and blood-brain barrier proteins predict delirium due to hip fracture in older adults

Introduction

Delirium is accompanied by immune response system activation, which may, in theory, cause a breakdown of the gut barrier and blood-brain barrier (BBB). Some results suggest that the BBB is compromised in delirium, but there is no data regarding the gut barrier. This study investigates whether delirium is associated with impaired BBB and gut barriers in elderly adults undergoing hip fracture surgery.

Methods

We recruited 59 older adults and measured peak Delirium Rating Scale (DRS) scores 2-3 days after surgery, and assessed plasma IgG/IgA levels (using ELISA techniques) for zonulin, occludin, claudin-6, β-catenin, actin (indicating damage to the gut paracellular pathway), claudin-5 and S100B (reflecting BBB damage), bacterial cytolethal distending toxin (CDT), LPS-binding protein (LBP), lipopolysaccharides (LPS), Porphyromonas gingivalis, and Helicobacter pylori.

Results

Results from univariate analyses showed that delirium is linked to increased IgA responses to all the self-epitopes and antigens listed above, except for LPS. Part of the variance (between 45-48.3%) in the peak DRS score measured 2-3 days post-surgery was explained by independent effects of IgA directed to LPS and LBP (or bacterial CDT), baseline DRS scores, and previous mild stroke. Increased IgA reactivity to the paracellular pathway and BBB proteins and bacterial antigens is significantly associated with the activation of M1 macrophage, T helper-1, and 17 cytokine profiles.

Conclusion

Heightened bacterial translocation, disruption of the tight and adherens junctions of the gut and BBB barriers, elevated CDT and LPS load in the bloodstream, and aberrations in cell-cell interactions may be risk factors for delirium.

A clinical study of non-bioartificial liver DPMAES support system in hepatitis B-related acute-on-chronic liver failure

This study aims to observe the clinical efficacy of the dual plasma molecular adsorption exchange system (DPMAES) in patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF), with a focus on its regulatory effect on cytokine storm. A total of 60 HBV-ACLF patients were enrolled in this study. The observation group, comprising 30 patients, received DPMAES treatment, while the control group underwent PE treatment. We compared the efficacy changes between the two groups post-treatment. A total of 55 HBV-ACLF patients who completed the study were analyzed, Patients treated with DPMAES showed significant improvements in clinical outcomes. After DPMAES treatment, HBV-ACLF patients exhibited notably 90 day survival rate increased by 18% compared to those in the PE group. Moreover, total bilirubin levels decreased markedly, albumin and platelet levels increased compared to the PE group. After DPMAES treatment, the patient showed a significant decrease in inflammatory cytokine IL-6 (t = 5.046, P < 0.001) and a significant decrease in procalcitonin (t = 4.66, P < 0.001). DPMAES was more effective than PE in rapidly reducing TBiL, improving coagulation function and mitigating cytokine storm. It maintained platelet stability more effectively while minimizing albumin consumption to a greater extent, significantly improved 90-day survival.Trial registration: Chinese Clinical Trial Registry, ChiCTR2300076117.

Recent Advances in the Pathogenesis and Clinical Evaluation of Portal Hypertension in Chronic Liver Disease

In chronic liver disease, hepatic stellate cell activation and degeneration of liver sinusoidal endothelial cells lead to structural changes, which are secondary to fibrosis and the presence of regenerative nodules in the sinusoids, and to functional changes, which are related to vasoconstriction. The combination of such changes increases intrahepatic vascular resistance and causes portal hypertension. The subsequent increase in splanchnic and systemic hyperdynamic circulation further increases the portal blood flow, thereby exacerbating portal hypertension. In clinical practice, the hepatic venous pressure gradient is the gold-standard measure of portal hypertension; a value of ≥10 mm Hg is defined as clinically significant portal hypertension, which is severe and is associated with the risk of liver-related events. Hepatic venous pressure gradient measurement is somewhat invasive, so evidence on the utility of risk stratification by elastography and serum biomarkers is needed. The various stages of cirrhosis are associated with different outcomes. In viral hepatitis-related cirrhosis, viral suppression or elimination by nucleos(t)ide analog or direct-acting antivirals results in recompensation of liver function and portal pressure. However, careful follow-up should be continued, because some cases have residual clinically significant portal hypertension even after achieving sustained virologic response. In this study, we reviewed the current and future prospects for portal hypertension.

Neutrophil activation and clonal CAR-T re-expansion underpinning cytokine release syndrome during ciltacabtagene autoleucel therapy in multiple myeloma

Cytokine release syndrome (CRS) is the most common complication of chimeric antigen receptor redirected T cells (CAR-T) therapy. CAR-T toxicity management has been greatly improved, but CRS remains a prime safety concern. Here we follow serum cytokine levels and circulating immune cell transcriptomes longitudinally in 26 relapsed/refractory multiple myeloma patients receiving the CAR-T product, ciltacabtagene autoleucel, to understand the immunological kinetics of CRS. We find that although T lymphocytes and monocytes/macrophages are the major overall cytokine source in manifest CRS, neutrophil activation peaks earlier, before the onset of severe symptoms. Intracellularly, signaling activation dominated by JAK/STAT pathway occurred prior to cytokine cascade and displayed regular kinetic changes. CRS severity is accurately described and potentially predicted by temporal cytokine secretion signatures. Notably, CAR-T re-expansion is found in three patients, including a fatal case characterized by somatic TET2-mutation, clonal expanded cytotoxic CAR-T, broadened cytokine profiles and irreversible hepatic toxicity. Together, our findings show that a latent phase with distinct immunological changes precedes manifest CRS, providing an optimal window and potential targets for CRS therapeutic intervention and that CAR-T re-expansion warrants close clinical attention and laboratory investigation to mitigate the lethal risk.

Interleukin-8 predicts short-term mortality in acute-on-chronic liver failure patients with hepatitis B-related-related cirrhosis background

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a distinctive and severe syndrome, marked by an excessive systemic inflammatory response. In vivo, interleukin 8 (IL-8) is an essential pro-inflammatory cytokine. We aimed to investigate the value of serum IL-8 levels in predicting mortality in ACLF patients in the background of hepatitis B virus-related cirrhosis.

METHODS

In this study, we conducted a retrospective analysis of the clinical baseline characteristics of 276 patients with ACLF in the context of HBV-related cirrhosis. Logistic regression analysis was employed to identify independent risk factors for short-, intermediate-, and long-term mortality. Using these independent risk factors, we developed a nomogram model, which was subsequently validated. To assess the clinical usefulness of the nomogram model, we performed decision curve analysis (DCA).

RESULTS

Out of the 276 patients with ACLF, 98 (35.5%), 113 (40.9%), and 128 (46.4%) died within 28, 90, and 180 days, respectively. Serum IL-8 levels were only an independent predictor of 28-day mortality and could simply classify ACLF patients. Conversely, mean arterial pressure (MAP), HBV-DNA, and COSHACLF IIs were independent predictors of mortality across all three observation periods. We constructed a nomogram based on IL-8 that was able to visualise and predict 28-day mortality with a C-index of 0.901 (95% CI: 0.862-0.940). Our calibration curves, Predicted Probability of Death & Actual Survival Status plot, and Confusion Matrix demonstrated the nomogram model's strong predictive power. DCA indicated the nomogram's promising clinical utility in predicting 28-day mortality in ACLF patients.

CONCLUSION

Serum IL-8 levels predict short-term mortality in ACLF patients in the background of HBV-associated cirrhosis, and the developed Nomogram model has strong predictive power and good clinical utility.

Markers of inflammation predict survival in newly diagnosed cirrhosis: a prospective registry study

The inflammatory activity in cirrhosis is often pronounced and related to episodes of decompensation. Systemic markers of inflammation may contain prognostic information, and we investigated their possible correlation with admissions and mortality among patients with newly diagnosed liver cirrhosis. We collected plasma samples from 149 patients with newly diagnosed (within the past 6 months) cirrhosis, and registered deaths and hospital admissions within 180 days. Ninety-two inflammatory markers were quantified and correlated with clinical variables, mortality, and admissions. Prediction models were calculated by logistic regression. We compared the disease courses of our cohort with a validation cohort of 86 patients with cirrhosis. Twenty of 92 markers of inflammation correlated significantly with mortality within 180 days (q-values of 0.00-0.044), whereas we found no significant correlations with liver-related admissions. The logistic regression models yielded AUROCs of 0.73 to 0.79 for mortality and 0.61 to 0.73 for liver-related admissions, based on a variety of modalities (clinical variables, inflammatory markers, clinical scores, or combinations thereof). The models performed moderately well in the validation cohort and were better able to predict mortality than liver-related admissions. In conclusion, markers of inflammation can be used to predict 180-day mortality in patients with newly diagnosed cirrhosis. Prediction models for newly diagnosed cirrhotic patients need further validation before implementation in clinical practice.Trial registration: NCT04422223 (and NCT03443934 for the validation cohort), and Scientific Ethics Committee No.: H-19024348.

Identification of oxidative stress-related biomarkers associated with the development of acute-on-chronic liver failure using bioinformatics

Acute-on-chronic liver failure (ACLF) is a serious stage of chronic liver disease with high short-term mortality and no definitely effective treatment. Oxidative stress (OS) is involved in the development of ACLF. OS-related genes targeted therapy may provide additional assistance for the treatment of ACLF. ACLF related gene sets and oxidative stress-related genes (OSGs) were respectively downloaded from gene expression omnibus (GEO) database and GeneCards database for integrated bioinformatics analyses (functional enrichment, weighted gene co-expression network and immune cells infiltration). Immune-related differentially expressed oxidative stress-related genes (DEOSGs) in ACLF were used for construction of protein-protein interaction (PPI) network in which hub genes were screened out. Hub genes with consistently good diagnostic or prognostic value for ACLF in four gene sets were named as key genes. DEOSGs were significantly enriched in biological process and signaling pathways related to inflammation, immune response and oxidative stress. Six key genes (MPO, CCL5, ITGAM, TLR2, TLR4, and TIMP1) were identified and found to be highly correlated with immune response and metabolic process. This study deepened our understanding of the impact of oxidative stress on the pathogenesis and prognosis of ACLF and provided more insights into the prediction of prognosis and molecular targeted therapy in ACLF.

A novel laboratory-based nomogram for assessing infection presence risk in acute-on-chronic liver failure patients

Accurate assessment of infection presence risk level, timely diagnosis, and effective control are critical for decreasing mortality of Acute‑on‑chronic liver failure (ACLF). We aimed to develop and validate a novel diagnostic model to accurately assess infection presence risk level in ACLF patients. 185 ACLF patients with/without infection were enrolled, and their demographic, physical findings, immune-inflammatory, hepatic function, metabolism, and coagulation-fibrinolysis indicators were analyzed. Regression analysis was performed to identify the independent diagnostic parameters, which were further used to establish diagnostic models with a nomogram for visual. An area under receiver operating characteristic curve (AUROC), calibration plots, clinical impact curves, decision curve analysis, and net reclassification index were used to evaluate and identify the best model. An external validating cohort was introduced to verify the diagnostic accuracy. We screened out white blood cell (WBC) count, LYM%, blood urea nitrogen (BUN), and D-dimer for assessing infection presence risk levels in ACLF patients. WBD (WBC + BUN + D-dimer) was established and proposed as a novel diagnostic model for infection presence risk levels assessment in ACLF patients with an AUROC of 0.803 (95%CI 0.723-0.883), 0.885 (95%CI 0.786-0.984) in training and external cohorts, respectively. In stratification analysis by ACLF etiology and stages, WBD achieved an AUROC of 0.791 (95%CI 0.691-0.891) and 0.873 (95%CI 0.78-0.966) in HBV-related and early-stage patients, respectively. Whereas a higher AUROC of 0.905 (95%CI 0.807-1.00) in the early-stage of HBV-related ACLF patients indicated its optimum application scope. WBD, a novel laboratory-based nomogram, can serve as a decision-making support tool for clinicians to assess infection presence risk levels in ACLF patients.

Predictive Value of the Prothrombin Time-International Normalized Ratio to Albumin Ratio in the Prognosis of Patients with Hepatitis B Virus-Related Acute-on-Chronic Liver Failure

Background

Acute-on-chronic liver failure is a common clinical syndrome with high short-term mortality, and early assessment of its mortality risk is crucial, but the search for valid and accurate prognostic biomarkers is a challenging endeavor. The purpose of this study was to investigate the predictive value of the prothrombin time-international normalized ratio to albumin ratio (PTAR) for mortality in patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF).

Patients and methods

A total of 354 patients with HBV-ACLF were included in the retrospective study. Patients were divided into survival and non-survival groups based on 90-day follow-up. Cox regression analysis was used to explore the relationship between PTAR and 90-day mortality in patients with HBV-ACLF. The area under the receiver operating characteristic curve was used to evaluate the effectiveness of PTAR in predicting mortality.

Results

PTAR was significantly higher in non-survivors than in survivors. The results of multivariate analysis showed that PTAR was a valid independent predictor of mortality in patients with HBV-ACLF. Its predictive ability for mortality was similar to that of the Child-Turcotte-Pugh score, the end-stage liver disease model (MELD) score, and the MELD-sodium score.

Conclusion

PTAR may be a simple and effective tool for predicting the prognosis of patients with HBV-ACLF.

Risk factors for the mortality of hepatitis B virus-associated acute-on-chronic liver failure: a systematic review and meta-analysis

BACKGROUND

Hepatitis B virus-associated acute-on-chronic liver failure (HBV-ACLF) has been confirmed as a prevalent form of end-stage liver disease in people subjected to chronic HBV infection. However, there has been rare in-depth research on the risk factors for the mortality of HBV-ACLF. This study aimed at determining the risk factors for the mortality of HBV-ACLF.

METHODS

The relevant research was selected from four electronic databases that have been published as of August 2023. The existing research was reviewed in accordance with the inclusion and exclusion criteria. The level of quality of previous research was evaluated using the Newcastle-Ottawa scale. Moreover, a pooled estimate of the odds ratios (ORs) with their associated 95% confidence intervals (CIs) was provided through a meta-analysis. The data were combined, and the risk variables that at least two studies had considered were analyzed. The publication bias was examined through Egger's test and Begg's test.

RESULTS

Twenty two studies that conformed to the inclusion criteria were selected from 560 trials. Eight risk variables in terms of HBV-ACLF mortality were determined, which covered INR (OR = 1.923, 95% CI = 1.664-2.221, P < 0.001), Monocytes (OR = 1.201, 95% CI = 1.113-1.296, P < 0.001), Cirrhosis (OR = 1.432, 95% CI = 1.210-1.696, P < 0.001), HE (OR = 2.553, 95% CI = 1.968-3.312, P < 0.001), HE grade (OR = 2.059, 95% CI = 1.561-2.717, P < 0.001), SBP (OR = 1.383, 95% CI = 1.080-1.769, P = 0.010), Hyponatremia (OR = 1.941, 95% CI = 1.614-2.334, P < 0.001), as well as HRS (OR = 2.610, 95% CI = 1.669-4.080, P < 0.001).

CONCLUSION

The most significant risk factors for HBV-ACLF mortality comprise HRS, HE, and HE grade, followed by INR and hyponatremia. The Monocytes, cirrhosis, and SBP have been confirmed as the additional key risk factors for HBV-ACLF mortality.

Role of inflammasomes and cytokines in immune dysfunction of liver cirrhosis

Liver cirrhosis develops as a result of persistent inflammation and liver injury. The prolonged inflammation triggers the buildup of fibrous tissue and regenerative nodules within the liver, leading to the distortion of the hepatic vascular structure and impaired liver function. Cirrhosis disrupts the ability of liver function to maintain homeostasis and hepatic immunosurveillance which causes immunological dysfunction in the body. In pathological conditions, the production of cytokines in the liver is carefully regulated by various cells in response to tissue stimulation. Cytokines and inflammasomes are the key regulators and systematically contribute to the development of cirrhosis which involves an inflammatory response. However, the crosstalk role of different cytokines in the cirrhosis progression is poorly understood. Tumour necrosis factor-alpha (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6), and interferon-gamma (IFN-γ), among others, are proinflammatory cytokines that contribute to liver cell necrosis, which in turn causes the development of fibrosis. While IL-10 exhibits a potent anti-inflammatory effect on the liver by inhibiting immune cell activation and neutralizing pro-inflammatory cytokine activity. Inflammasomes have also been implicated in the profibrotic processes of liver cirrhosis, as well as the production of chemokines such as CCL2/MCP-1. It is evident that inflammasomes have a role in the proinflammatory response seen in chronic liver illnesses. In conclusion, cirrhosis significantly impacts the immune system, leading to immunological dysfunction and alterations in both innate and acquired immunity. Proinflammatory cytokines like TNF-α, IL-1β, IL-6, and IFNγ are upregulated in cirrhosis, contributing to liver cell necrosis and fibrosis development. Managing cytokine-mediated inflammation and fibrosis is a key therapeutic approach to alleviate portal hypertension and its associated liver complications. This review attempted to focus largely on the role of immune dysfunction mediated by different cytokines and inflammasomes involved in the progression, regulation and development of liver cirrhosis.

Knockdown of CXCL1 improves ACLF by reducing neutrophil recruitment to attenuate ROS production and hepatocyte apoptosis

BACKGROUND

Acute-on-chronic liver failure (ACLF) is an acute decompensated syndrome based on chronic liver disease, while neutrophil recruitment is the most critical early step. C-X-C motif chemokine ligand 1 (CXCL1), a cytokine that recruits neutrophils, was significantly upregulated in both ACLF mice and patients with ACLF. This present study aims to explore the role of CXCL1 in the pathogenesis of ACLF.

METHODS

We established an ACLF mouse model induced by carbon tetrachloride, lipopolysaccharide, and D-galactosamine, and used adeno-associated virus to achieve overexpression and knockdown of Cxcl1. We employed mass cytometry, flow cytometry, multiplex cytokine and chemokine analysis, Western blot, and reactive oxygen species (ROS) detection in mice blood and liver. ACLF patients (n = 10) and healthy controls (n = 5) were included, and their liver samples were stained using multiplex immunohistochemistry techniques.

RESULTS

CXCL1 was significantly elevated in both ACLF mice and patients. CXCL1 recruits neutrophils by binding to the C-X-C motif chemokine receptor 2 on the surface of neutrophils, affects ACLF prognosis by generating ROS and mitochondrial depolarization and modulating caspase3-related apoptotic pathways. We found that the knockdown of CXCL1 attenuated the infiltration of neutrophils in the mouse liver, reduced the expression of inflammatory cytokines, and also significantly downregulated ROS production and caspase3-related hepatocyte apoptosis, thereby ameliorating the liver injury of ACLF.

CONCLUSIONS

CXCL1 is a core player in the mobilization of neutrophils in ACLF, and the knockdown of Cxcl1 improves neutrophil infiltration, reduces ROS levels, and reduces hepatocyte apoptosis, thereby attenuating inflammation and liver injury in ACLF. Our results revealed a previously unknown link between CXCL1-induced neutrophil recruitment and ACLF, providing evidencing for potential therapies targeting ACLF.

Mechanisms and treatment approaches for ACLF

Acute-on-chronic liver failure (ACLF) is a life-threatening syndrome characterized by decompensation of cirrhosis, severe systemic inflammation and organ failures. ACLF is frequently triggered by intra- and/or extrahepatic insults, such as bacterial infections, alcohol-related hepatitis or flares of hepatic viruses. The imbalance between systemic inflammation and immune tolerance causes organ failures through the following mechanisms: (i) direct damage of immune cells/mediators; (ii) worsening of circulatory dysfunction resulting in organ hypoperfusion and (iii) metabolic alterations with prioritization of energetic substrates for inflammation and peripheral organ 'energetic crisis'. Currently, the management of ACLF includes the support of organ failures, the identification and treatment of precipitating factors and expedited assessment for liver transplantation (LT). Early LT should be considered in patients with ACLF grade 3, who are unlikely to recover with the available treatments and have a mortality rate > 70% at 28 days. However, the selection of transplant candidates and their prioritization on the LT waiting list need standardization. Future challenges in the ACLF field include a better understanding of pathophysiological mechanisms leading to inflammation and organ failures, the development of specific treatments for the disease and personalized treatment approaches. Herein, we reviewed the current knowledge and future perspectives on mechanisms and treatment of ACLF.

Extracorporeal albumin dialysis in critically ill patients with liver failure: Comparison of four different devices-A retrospective analysis

BACKGROUND

Besides standard medical therapy and critical care monitoring, extracorporeal liver support may provide a therapeutic option in patients with liver failure. However, little is known about detoxification capabilities, efficacy, and efficiency among different devices.

METHODS

Retrospective single-center analysis of patients treated with extracorporeal albumin dialysis. Generalized Estimating Equations with robust variance estimator were used to account for repeated measurements of several cycles and devices per patient.

RESULTS

Between 2015 and 2021 n = 341 cycles in n = 96 patients were eligible for evaluation, thereof n = 54 (15.8%) treatments with Molecular Adsorbent Recirculating System, n = 64 (18.7%) with OpenAlbumin, n = 167 (48.8%) Advanced Organ Support treatments, and n = 56 (16.4%) using Single Pass Albumin Dialysis. Albumin dialysis resulted in significant bilirubin reduction without differences between the devices. However, ammonia levels only declined significantly in ADVOS and OPAL. First ECAD cycle was associated with highest percentage reduction in serum bilirubin. With the exception of SPAD all devices were able to remove the water-soluble substances creatinine and urea and stabilized metabolic dysfunction by increasing pH and negative base excess values. Platelets and fibrinogen levels frequently declined during treatment. Periprocedural bleeding and transfusion of red blood cells were common findings in these patients.

CONCLUSIONS

From this clinical perspective ADVOS and OPAL may provide higher reduction capabilities of liver solutes (i.e. bilirubin and ammonia) in comparison to MARS and SPAD. However, further prospective studies comparing the effectiveness of the devices to support liver impairment (i.e. bile acid clearance or albumin binding capacity) as well as markers of renal recovery are warranted.

The high level of IL-1β in the serum of ACLF patients induces increased IL-8 expression in hUC-MSCs and reduces the efficacy of hUC-MSCs in liver failure

BACKGROUND

Stem cells play a therapeutic role mainly through immunoregulation. However, the immunomodulatory function of stem cells may be affected by inflammation-related factors in patients' serum. Therefore, this study aims to investigate the possible mechanism by which acute-on-chronic liver failure (ACLF) patient serum influences the efficacy of hUC-MSCs.

METHODS

The serum of surviving and dead ACLF patients was collected to culture hUC-MSCs in vitro, and the hUC-MSCs cultured in the serum of ACLF patients were used to treat acute liver failure (ALF) rats. The therapeutic effect on the rats was evaluated by a survival curve, the transaminase level and liver histopathology. The expression of cytokines in hUC-MSCs was detected by Q-PCR and ELISA.

RESULTS

Serum pretreatment reduced the therapeutic effect of hUC-MSCs on ALF, especially pretreatment in the serum from dead ACLF patients. After hUC-MSCs were cultured in the serum of surviving or dead ACLF patients, the most differentially expressed factor was IL-8. Interfering with the expression of IL-8 in hUC-MSCs can improve the therapeutic effect of hUC-MSCs on ALF. The high level of IL-1β in the serum of dead ACLF patients causes the increased expression of IL-8 in hUC-MSCs through the activation of the NF-κB signaling pathway. Meanwhile, we found that the neutralizing IL-1β in serum from dead ACLF patients can improve the therapeutic effect of hUC-MSCs on ALF.

CONCLUSION

The high level of IL-1β in ACLF serum can promote the expression of IL-8 in hUC-MSCs through the NF-κB signaling pathway, thus reducing the effect of hUC-MSCs on ALF.

Bacterial Infections in Acute on Chronic Liver Failure

Bacterial infections (BIs) are the most common precipitating event of acute-on-chronic liver failure (ACLF) and a frequent complication of ACLF. BIs aggravate the course of the syndrome and are associated with higher mortality rates. For this reason, BIs should be promptly diagnosed and treated in all patients with ACLF. The administration of an appropriate empirical antibiotic therapy improves survival in patients with BIs and ACLF and is the cornerstone of treatment. Due to the spread of antibiotic resistance worldwide, the empirical treatment should cover multi-drug-resistant organisms. Herein we reviewed the current evidence about the management of BIs in ACLF.

COVID-19 Disease in Pediatric Solid Organ Transplantation from Alpha to Omicron: A High Monocyte Count in the Preceding Three Months Portends a Risk for Severe Disease

IMPORTANCE

Planning for future resurgences in SARS-CoV-2 infection is necessary for providers who care for immunocompromised patients.

OBJECTIVE

to determine factors associated with COVID-19 disease severity in immunosuppressed children.

DESIGN

a case series of children with solid organ transplants diagnosed with SARS-CoV-2 infection between 15 March 2020 and 31 March 2023.

SETTING

a single pediatric transplant center.

PARTICIPANTS

all children with a composite transplant (liver, pancreas, intestine), isolated intestine transplant (IT), isolated liver transplant LT), or simultaneous liver kidney transplant (SLK) with a positive PCR for SARS-CoV-2.

EXPOSURE

SARS-CoV-2 infection.

MAIN OUTCOME AND MEASURES

We hypothesized that children on the most immunosuppression, defined by the number of immunosuppressive medications and usage of steroids, would have the most severe disease course and that differential white blood cell count in the months preceding infection would be associated with likelihood of having severe disease. The hypothesis being tested was formulated during data collection. The primary study outcome measurement was disease severity defined using WHO criteria.

RESULTS

77 children (50 LT, 24 intestine, 3 SLK) were infected with SARS-CoV-2, 57.4 months from transplant (IQR 19.7-87.2). 17% were ≤1 year post transplant at infection. 55% were male, 58% were symptomatic and ~29% had severe disease. A high absolute lymphocyte count at diagnosis decreased the odds of having severe COVID-19 disease (OR 0.29; CI 0.11-0.60; p = 0.004). Conversely, patients with a high absolute monocyte count in the three months preceding infection had increased odds of having severe disease (OR 30.49; CI 1.68-1027.77; p = 0.033). Steroid use, higher tacrolimus level, and number of immunosuppressive medications at infection did not increase the odds of having severe disease.

CONCLUSIONS AND RELEVANCE

The significance of a high monocyte count as predictor of severe disease potentially confirms the importance of monocytic inflammasome-driven inflammation in COVID-19 pathogenesis. Our data do not support reducing immunosuppression in the setting of infection. Our observations may have important ramifications in resource management as vaccine- and infection-induced immunity wanes.

Utility of neutrophil-lymphocyte ratio and platelet-lymphocyte ratio in predicting acute-on-chronic liver failure survival

This study explored the predictive value of the monocyte-to-lymphocyte ratio (MLR) and platelet-lymphocyte ratio (PLR) in patients with acute-on-chronic liver failure (ACLF). A retrospective analysis was carried out on 40 patients with ACLF from January 2018 and August 2019 in our hospital. The patient's clinical information during hospitalization was collected, and their survivals were followed for 3 months. MLR and PLR values of patients were compared, and the correlation between liver function indicators and prognosis was analyzed. We observed that MLR levels in the survival and death groups were 0.521 (0.311, 0.827) and 0.741 (0.442, 1.121), respectively. MLR levels were markedly enhanced in the death group compared to the survival group (P = 0.021). The receiver operating characteristic curve (ROC) exhibited that the area under the ROC curve and 95% confidence interval for the survival group was 0.641 (0.528-0.757). Survival analysis demonstrated that the 3-month survival of the high MLR group was markedly lower than that of the low MLR group (P = 0.001). Multivariate regression exposed that MLR and PLR were independent prognostic factors for ACLF. MLR and PLR could be prospective prognosticative markers of ACLF.

Plasma S100A8 and S100A9 Are Strong Prognostic Factors for Hepatitis B Virus-Related Acute-on-Chronic Liver Failure

Objectives

The rapidly evolving organ failure and high short-run mortality of acute-on-chronic liver failure (ACLF) are inseparable from the role of systemic inflammatory response. S100A8 and S100A9 are associated with the excessive cytokine storm and play a decisive part within the process of inflammation. We aimed to clarify the role of them in predicting prognosis of hepatitis B virus-related ACLF (HBV-ACLF).

Methods

S100A8 and S100A9 levels were analyzed in plasma of 187 transplant-free HBV-ACLF patients, 28 healthy controls and 40 chronic hepatitis B (CHB) patients. S100A8 and S100A9 mRNAs were checked in liver samples from 32 HBV-ACLF patients with liver transplantation, 19 patients undergoing surgery for hepatic hemangioma and 10 CHB patients with needle biopsy.

Results

The plasma levels of the S100A8 and S100A9 were higher in HBV-ACLF patients than in CHB patients (S100A8 : P < 0.001 and S100A9 : P < 0.001) and healthy controls (S100A8 : P < 0.001 and S100A9 : P < 0.001), and similar results were obtained for mRNA expression. Moreover, both proteins were related to ACLF grade, different types of organ failure, and infection, and they correlated with other prognostic scoring systems. S100A8 and S100A9 can dependently predict 28/90-day mortality (28-day: S100A8: hazard ratio (HR): 1.027; 95% confidence interval (CI): 1.007-1.048; P=0.026, S100A9 : HR: 1.009; 95% CI: 1.001-1.017; P=0.007, 90-day: S100A8 : HR: 1.023; 95% CI: 1.011-1.035; P=0.004, S100A9 : HR: 1.008; 95% CI: 1.004-1.012; and P < 0.001). Among all of the scoring systems, the combined scoring model (S100A8 and S100A9 jointly with the Chronic Liver Failure-Consortium Organ Failure score (CLIF-C OFs)) displayed the highest area under the receiver operating curve (0.923 (95% CI, 0.887-0.961)) in the prediction of 90-day mortality.

Conclusions

S100A8 and S100A9 are promising biomarkers for the analysis of risk stratification and prognosis in ACLF patients. In addition, combining them with the CLIF-C OFs may better predict the prognosis of ACLF.

The value of NLR versus MLR in the short-term prognostic assessment of HBV-related acute-on-chronic liver failure

BACKGROUND

Systemic inflammation is associated with the development and progression of hepatitis B-associated acute-on-chronic liver failure (HBV-ACLF). The neutrophil-to-lymphocyte ratio (NLR) has been reported to be a prognostic biomarker in patients with HBV-ACLF. However, the role of the monocyte-to-lymphocyte ratio (MLR) as a prognostic inflammatory biomarker in multiple diseases is rarely mentioned in HBV-ACLF.

METHODS

We included a total of 347 patients with HBV-ACLF who met the definition of the Chinese Guidelines for the Diagnosis and Treatment of Liver Failure (2018 edition). Among them, 275 cases were included retrospectively, and 72 cases were collected prospectively. Clinical characteristics and laboratory examination data were collected from medical records within 24 h after diagnosis to calculate MLR and NLR levels, and lymphocyte subpopulation counts were collected in prospectively included patients.

RESULTS

Of the 347 patients with HBV-ACLF, 128 patients in the non-surviving group had a mean age of 48.87 ± 12.89 years; 219 patients in the survival group had a mean age of 44.80 ± 11.80 years and a combined 90-day mortality rate of 36.9%. The median MLR was higher in the non-survivors than in the survivors (0.690 vs 0.497, P < 0.001). MLR values were significantly associated with 90-day mortality in HBV-ACLF (OR 6.738; 95% CI 3.188-14.240, P < 0.001). The AUC for the predictive power of the combined MLR and NLR analysis for HBV-ACLF was 0.694, and the calculated MLR threshold was 4.495. In addition, in the analysis of peripheral blood lymphocyte subsets in HBV-ACLF, a significant decrease in the number of circulating lymphocytes was found in HBV-ACLF patients in the non-surviving group (P < 0.001), with a predominant decrease in the number of CD8 + T cells and no significant difference in the number of CD4 + T cells, B cells or NK cells.

CONCLUSION

Increased MLR values are associated with 90-day mortality in patients with HBV-ACLF, and the MLR may serve as a potential prognostic indicator for patients with HBV-ACLF. Decreased CD8 + T-cell counts may be associated with poor survival in patients with HBV-ACLF.

Saturated fatty acids synergizes cadmium to induce macrophages M1 polarization and hepatic inflammation

Exposure to the toxic metal cadmium (Cd) is a well-established risk factor for hepatic inflammation, but it remains unclear how metabolic components, such as different fatty acids (FAs), interact with Cd to influence this process. Understanding these interactions is essential for identifying potential preventative and therapeutic targets for this disorder. To address this question, we conducted in vitro and in vivo studies to investigate the combinatorial effect of Cd and saturated FAs on hepatic inflammation. Specifically, we assessed the cytotoxicity of Cd on macrophages and their polarization and inflammatory activation upon co-exposure to Cd and saturated FAs. Our results showed that while saturated FAs had minimal impact on the cytotoxicity of Cd on macrophages, they significantly collaborated with Cd in predisposing macrophages towards a pro-inflammatory M1 polarization, thereby promoting inflammatory activation. This joint effect of Cd and saturated FAs resulted in persistent inflammation and hepatic steatohepatitis in vivo. In summary, our study identified macrophage polarization as a novel mechanism by which co-exposure to Cd and saturated lipids induces hepatic inflammation. Our findings suggest that intervening in macrophage polarization may be a potential approach for mitigating the adverse hepatic effects of Cd.

Efficacy and Economic Evaluation of Nonbiological Artificial Liver Therapy in Acute-on-chronic Hepatitis B Liver Failure

BACKGROUND AND AIMS

Nonbiological artificial liver (NBAL) is frequently used as a first-line treatment for hepatitis B virus-associated acute-on-chronic liver failure (HBV-ACLF). This study aimed to compare the therapeutic efficacy and cost-effectiveness ratio (CER) of comprehensive medical treatment, plasma exchange (PE), and double plasma molecular adsorption system (DPMAS) plus half-dose PE (DPMAS+PE) in patients with HBV-ACLF.

METHODS

A total of 186 patients with HBV-ACLF randomly received comprehensive medical treatment, PE, or DPMAS+PE and were prospectively evaluated. Patients were divided into four subgroups based on the pretreatment prothrombin activity (PTA): Group I (PTA>40%), group II (PTA 30-40%), group III (PTA 20-30%), and group IV (PTA<20%). The main outcome measures were 28 day effectiveness; 90 day liver transplantation-free survival; change of biochemical parameters; and CER.

RESULTS

DPMAS+PE treatment was associated with significantly higher 28 day effectiveness and 90 day liver transplantation-free survival compared with PE treatment in patients with group I liver failure. Clearance of serum total bilirubin (TBIL), AST, and creatinine (Cr) were significantly higher in the DPMAS+PE group than in the PE group. For subjects with group I liver failure, DPMAS+PE treatment had advantages of lower CER values and better cost-effectiveness.

CONCLUSIONS

Compared with comprehensive medical treatment and PE alone, DPMAS with half-dose sequential PE treatment more effectively improved TBIL, AST, and Cr in HBV-ACLF patients, improved 28 day effectiveness and 90 day survival rates in patients with group I liver failure, and was more cost effective. DPMAS+PE is a viable NBAL approach for treatment of HBV-ACLF.

Short-Term and Long-Term Outcomes of Liver Cirrhosis in Gastric Neoplasm Patients Undergoing Endoscopic Submucosal Dissection

Purpose: The purpose of this study was to explore whether liver cirrhosis (LC) influences short-term and long-term outcomes in gastric neoplasm patients who undergo endoscopic submucosal dissection (ESD). Materials and Methods: Eligible studies were identified in three databases, including PubMed, Embase, and the Cochrane Library on December 18, 2022. Clinical characteristics, short-term outcomes, and long-term outcomes were compared between an LC group and a no liver cirrhosis (NLC) group. For continuous variables, the mean difference (MD) and standard deviation (SD) were pooled. For discontinuous variables, raw data from the 2 × 2 tables or odds ratio (OR) and 95% confidence intervals (CIs) were pooled. Forest plots were used to show the results, and a funnel plot was used to evaluate publication bias. Data analyses were performed by STATA SE 16.0 software. Results: Six retrospective studies involving 1616 gastric neoplasm patients were included in the study. Clinical characteristics, including age, gender, location, macroscopic type, invasion depth, differentiation, and ulceration, were found to be not significantly different between the LC group and the NLC group (P > .05). Moreover, LC was not a risk factor for short-term outcomes, including operative time (MD = 0.15, 95% CI = -0.02 to 0.32, I² = 0.00%, P = .09), en bloc resection (OR = 0.87, 95% CI = 0.43-1.75, I² = 0.00%, P = .69), R0 resection (OR = 0.77, 95% CI = 0.42-1.43, I² = 8.97%, P = .41), bleeding (OR = 1.10, 95% CI = 0.62-1.93, I² = 0.00%, P = .75), and perforation (OR = 1.62, 95% CI = 0.45-5.84, I² = 0.00%, P = .46). However, gastric cancer patients with LC exhibited a higher recurrence rate (OR = 3.40, 95% CI = 1.09-10.61, I² = 0.00%, P = .04) after ESD. Conclusion: Surgeons performing ESD in gastric neoplasm patients should pay more attention to long-term effects.

DLL4-Notch signalling in acute-on-chronic liver failure: State of the art and perspectives

Acute-on-chronic liver failure (ACLF) is a syndrome characterized by acute decompensation of chronic liver disease associated with multiple-organ failures and high short-term mortality. Acute insults to patients with chronic liver disease can lead to ACLF, among which, hepatitis B virus-related ACLF is the most common type of liver failure in the Asia-Pacific region. Currently, immune-metabolism disorders and systemic inflammation are proposed to be the main mechanisms of ACLF. The resulting cholestasis and intrahepatic microcirculatory dysfunction accelerate the development of ACLF. Treatments targeting immune regulation, metabolic balance, microcirculation maintenance and bile duct repair can alleviate inflammation and restore the tissue structure. An increasing number of studies have demonstrated that delta-like ligand 4 (DLL4), one of the Notch signalling ligands, plays a vital role in immune regulation, metabolism, angiogenesis, and biliary regeneration, which participate in liver pathological and physiological processes. The detailed mechanism of the DLL4-Notch signalling pathway in ACLF has rarely been investigated. Here, we review the evidence showing that DLL4-Notch signalling is involved in ACLF and analyse the potential role of DLL4 in the treatment of ACLF.

Pooled Analysis of Mesenchymal Stromal Cell-Derived Extracellular Vesicle Therapy for Liver Disease in Preclinical Models

Background: Although increasing preclinical studies have emphasized the benefits of exosome-related therapies, the efficacy of mesenchymal stromal cell (MSC)-derived extracellular vesicles (EV) for liver injury is unclear. In this work, a pooled analysis was conducted to explore the overall effect of MSC-EV in animal models. Methods: A systematic search of the PubMed, EMBASE, Web of Science, and Cochrane Library databases was performed, from initiation to February 2022, for preclinical studies with liver disease models. The treatment outcomes were evaluated based on liver function, histological analysis, and inflammatory cytokines. Results: After screening, 39 studies were included. Pooled analyses demonstrated that MSC-EV therapy significantly improved liver functions (ALB, ALT, AST, ALP, and γ-GT), promoted the repair of injured liver tissue (damaged area, Ishak’s score), reduced inflammatory factors (TNF-α, IL-1β, IL-6, and IFN-γ), and increased an anti-inflammatory cytokine (IL-10) compared to the placebo control group. Subgroup analyses indicated that MSC-EV had therapeutic effects on liver fibrosis (n = 16), acute liver injury (n = 11), non-alcoholic fatty liver disease (n = 3), autoimmune hepatitis (n = 4), and hepatic ischemia-reperfusion injury (n = 6). Additionally, the therapeutic effect of EV was comparable to that of MSCs. Conclusion: MSC-EV have therapeutic potential for acute and chronic liver diseases.

Potential therapies for acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is a syndrome that develops in approximately 30% of patients hospitalised with cirrhosis and is characterised by an acute decompensation of liver function associated with extra-hepatic organ failures and a high short-term mortality. At present, no specific therapies are available for ACLF, and current management is limited to treatment of the precipitating event and organ support. Given the high prevalence and high mortality of this severe liver disease, there is an urgent need for targeted treatments. There is increasing evidence of the important role played by systemic inflammation and immune dysfunction in the pathophysiology of ACLF and a better understanding of these immune processes is resulting in new therapeutic targets. The aim of this review is to present an overview of ongoing studies of potentially promising therapies and how they could be utilised in the management of ACLF.

The progress to establish optimal animal models for the study of acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) defines a complicated and multifaceted syndrome characterized by acute liver dysfunction following an acute insult on the basis of chronic liver diseases. It is usually concurrent with bacterial infection and multi-organ failure resulting in high short-term mortality. Based on the cohort studies in ACLF worldwide, the clinical course of ACLF was demonstrated to comprise three major stages including chronic liver injury, acute hepatic/extrahepatic insult, and systemic inflammatory response caused by over-reactive immune system especially bacterial infection. However, due to the lack of optimal experimental animal models for ACLF, the progress of basic study on ACLF is limping. Though several experimental ACLF models were established, none of them can recapitulate and simulate the whole pathological process of ACLF patients. Recently, we have developed a novel mouse model for ACLF combining chronic liver injury [injection of carbon tetrachloride (CCl₄) for 8 weeks], acute hepatic insult (injection of a double dose CCl₄), and bacterial infection (intraperitoneal injection of Klebsiella pneumoniae), which could recapitulate the major clinical features of patients with ACLF worsened by bacterial infection.

Serum cytokine and chemokine profiles and disease prognosis in hepatitis B virus-related acute-on-chronic liver failure

Background

Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) has significant morbidity and mortality and is associated with the induction of cytokines/chemokines, which might contribute to the pathogenesis of liver injury. This study aimed to explore the cytokine/chemokine profiles of patients with HBV-ACLF and develop a composite clinical prognostic model.

Methods

We prospectively collected blood samples and the clinical data of 107 patients with HBV-ACLF admitted to the Beijing Ditan Hospital. The concentrations of 40-plex cytokines/chemokines were measured in 86 survivors and 21 non-survivors using the Luminex assay. Discrimination between the cytokine/chemokine profiles in different prognosis groups was analyzed using the multivariate statistical techniques of principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). An immune-clinical prognostic model was obtained using multivariate logistic regression analysis.

Results

The PCA and PLS-DA indicated that cytokine/chemokine profiling could clearly distinguish patients with different prognoses. A total of 14 cytokines, namely, IL-1β, IL-6, IL-8, IL-10, TNF-α, IFN-γ, CXCL1, CXCL2, CXCL9, CXCL13, CX3CL1, GM-SCF, CCL21, and CCL23, were significantly correlated with disease prognosis. Multivariate analysis identified CXCL2, IL-8, total bilirubin, and age as independent risk factors that constituted the immune-clinical prognostic model, which showed the strongest predictive value of 0.938 compared with those of the Chronic Liver Failure Consortium (CLIF-C) ACLF (0.785), Model for End-Stage Liver Disease (MELD) (0.669), and MELD-Na (0.723) scores (p < 0.05 for all).

Conclusion

The serum cytokine/chemokine profiles correlated with the 90-day prognosis of patients with HBV-ACLF. The proposed composite immune-clinical prognostic model resulted in more accurate prognostic estimates than those of the CLIF-C ACLF, MELD, and MELD-Na scores.

Emerging Therapeutic Targets for Portal Hypertension

Purpose of Review

Portal hypertension is responsible of the main complications of cirrhosis, which carries a high mortality. Recent treatments have improved prognosis, but this is still far from ideal. This paper reviews new potential therapeutic targets unveiled by advances of key pathophysiologic processes.

Recent Findings

Recent research highlighted the importance of suppressing etiologic factors and a safe lifestyle and outlined new mechanisms modulating portal pressure. These include intrahepatic abnormalities linked to inflammation, fibrogenesis, vascular occlusion, parenchymal extinction, and angiogenesis; impaired regeneration; increased hepatic vascular tone due to sinusoidal endothelial dysfunction with insufficient NO availability; and paracrine liver cell crosstalk. Moreover, pathways such as the gut-liver axis modulate splanchnic vasodilatation and systemic inflammation, exacerbate liver fibrosis, and are being targeted by therapy. We have summarized studies of new agents addressing these targets.

Summary

New agents, alone or in combination, allow acting in complementary mechanisms offering a more profound effect on portal hypertension while simultaneously limiting disease progression and favoring regression of fibrosis and of cirrhosis. Major changes in treatment paradigms are anticipated.

Research progress on short-term prognosis of acute-on-chronic liver failure

INTRODUCTION

Acute-on-chronic liver failure (ACLF) is a clinical syndrome characterized as a severe condition with rapid progression, poor therapeutic response and poor prognosis. Early and timely evaluation of the prognosis is helpful for providing appropriate clinical intervention and prolonging patient survival.

AREAS COVERED

Currently, there are no specific dynamic and comprehensive approaches to assess the prognosis of patients with ACLF. This article reviews the progress in evaluating the short-term prognosis of ACLF to provide future directions for more dynamic prospective large-scale multicenter studies and a basis for individualized and precise treatment for ACLF patients. We searched PubMed and Web of Science with the term 'acute on chronic liver failure' and 'prognosis.' There was no date or language restriction, and our final search was on 26 October 2022.

EXPERT OPINION

ACLF is a dynamic process, and the best prognostic marker is the clinical evolution of organ failure over time. New prognostic markers are developing not only in the fields of genetics and histology but also toward diversification combined with imaging. Determining which patients will benefit from continued advanced life support is a formidable challenge, and accurate short-term prognostic assessments of ACLF are a good approach to addressing this issue.

Liver support systems for adults with acute‐on‐chronic liver failure

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the benefits and harms of liver support systems for adults with acute‐on‐chronic liver failure.

Colonization with Carbapenem-Resistant Enterobacteriaceae Contributes to Unfavorable Outcomes in End-Stage Liver Disease Patients

Carbapenem-resistant Enterobacteriaceae (CRE) are the highest priority pathogens of the World Health Organization, and their prevalence in end-stage liver disease (ESLD) patients is increasing. CRE colonization is an independent risk factor for CRE infections. We aimed to assess risk factors and explore the relationship between CRE colonization, infection, and prognosis in patients with ESLD. A total of 311 patients with ESLD were screened for CRE colonization by fecal swabs from October 2020 to January 2022. Antimicrobial susceptibility was tested using the broth microdilution method. Carbapenem resistance genes, multilocus sequence type, and capsular serotype were analyzed by polymerase chain reaction (PCR). Seventeen CRE strains were detected, among which the most common was Klebsiella pneumoniae. The CRE colonization rate was 5.5%. Artificial liver support was an independent risk factor for CRE colonization. Compared to the non-CRE colonization group, the colonization group had a higher incidence of CRE infection and a worse prognosis. Furthermore, these strains were not closely related, and all were sensitive to polymyxin and tigecycline. There was a high colonization rate in ESLD patients, and colonization strains were highly diverse. CRE colonization deserves attention in these patients, especially when treated with artificial liver support.

A practical nomogram based on serum interleukin-6 for the prognosis of liver failure

BACKGROUND

Liver failure (LF) is a serious liver function damage caused by various factors, mainly jaundice, hepatic encephalopathy, coagulation disorders and multiple organ failure, with the clinical characteristic of high short-term mortality. LF is often accompanied by excessive activation of inflammatory factors, and an excessive systemic inflammatory response (i.e., inflammatory storm) is considered to be the trigger of LF. However, a specific prognostic model including inflammatory factors for patients with LF has not been well established.

AIM

To establish and validate a nomogram for predicting 28-day, 90-day, and 180-day mortality in patients with LF.

METHODS

A total of 423 eligible LF patients were enrolled in this retrospective study. Independent predictors were identified using a multivariate logistic model and then integrated into a nomogram to predict 28-day, 90-day, and 180-day mortality. The concordance index, receiver operating characteristic curves, and calibration plots were used to evaluate the performance of the model.

RESULTS

Sex, age, total bilirubin, aspartate aminotransferase, international normalized ratio, Child-Pugh score, and serum interleukin-6 were independent risk factors for death at 28, 90, and 180 days in LF patients. The nomogram showed good calibration and discrimination with an area under the receiver operating characteristic curve (AUC) of 0.927. The calibration curve fit as well, indicating that the nomogram had good clinical application value.

CONCLUSION

This nomogram model for predicting the 28-day, 90-day, and 180-day mortality of LF patients could help optimize treatment strategies and improve prognosis.

The Mechanisms of Systemic Inflammatory and Immunosuppressive Acute-on-Chronic Liver Failure and Application Prospect of Single-Cell Sequencing

Acute-on-chronic liver failure (ACLF) is a complex clinical syndrome, and patients often have high short-term mortality. It occurs with intense systemic inflammation, often accompanied by a proinflammatory event (such as infection or alcoholic hepatitis), and is closely related to single or multiple organ failure. Liver inflammation begins when innate immune cells (such as Kupffer cells (KCs)) are activated by binding of pathogen-associated molecular patterns (PAMPs) from pathogenic microorganisms or damage-associated molecular patterns (DAMPs) of host origin to their pattern recognition receptors (PRRs). Activated KCs can secrete inflammatory factors as well as chemokines and recruit bone marrow-derived cells such as neutrophils and monocytes to the liver to enhance the inflammatory process. Bacterial translocation may contribute to ACLF when there are no obvious precipitating events. Immunometabolism plays an important role in the process (including mitochondrial dysfunction, amino acid metabolism, and lipid metabolism). The late stage of ACLF is mainly characterized by immunosuppression. In this process, the dysfunction of monocyte and macrophage is reflected in the downregulation of HLA-DR and upregulation of MER tyrosine kinase (MERTK), which weakens the antigen presentation function and reduces the secretion of inflammatory cytokines. We also describe the specific function of bacterial translocation and the gut-liver axis in the process of ACLF. Finally, we also describe the transcriptomics in HBV-ACLF and the recent progress of single-cell RNA sequencing as well as its potential application in the study of ACLF in the future, in order to gain a deeper understanding of ACLF in terms of single-cell gene expression.

The role of platelet mediated thromboinflammation in acute liver injury

Acute liver injuries have wide and varied etiologies and they occur both in patients with and without pre-existent chronic liver disease. Whilst the pathophysiological mechanisms remain distinct, both acute and acute-on-chronic liver injury is typified by deranged serum transaminase levels and if severe or persistent can result in liver failure manifest by a combination of jaundice, coagulopathy and encephalopathy. It is well established that platelets exhibit diverse functions as immune cells and are active participants in inflammation through processes including immunothrombosis or thromboinflammation. Growing evidence suggests platelets play a dualistic role in liver inflammation, shaping the immune response through direct interactions and release of soluble mediators modulating function of liver sinusoidal endothelial cells, stromal cells as well as migrating and tissue-resident leucocytes. Elucidating the pathways involved in initiation, propagation and resolution of the immune response are of interest to identify therapeutic targets. In this review the provocative role of platelets is outlined, highlighting beneficial and detrimental effects in a spatial, temporal and disease-specific manner.

Effect of the change in antiviral therapy indication on identifying significant liver injury among chronic hepatitis B virus infections in the grey zone

Objective

In clinical practice, a substantial proportion of chronic hepatitis B virus (HBV) infections that do not fit into any of the usual immune states are considered to be in the “grey zone (GZ)”. This study aimed to investigate the effect of the change in antiviral therapy indication on identifying significant hepatic injury among GZ patients.

Methods

Patients with chronic HBV infections and a persistent normal alanine aminotransferase (ALT) level (PNALT) who underwent ultrasonography-guided percutaneous liver biopsy were examined retrospectively. Evidenced hepatic injury (EHI) was defined as an inflammation grade ≥2 (≥G2) and/or fibrosis stage ≥2 (≥F2). Complete clinical data, liver inflammation, and fibrosis grades were collected, and the levels of cytokines were detected by the Luminex technique, all of which were analysed to investigate the immune and histopathology states of the liver.

Results

A total of 347 patients with chronic HBV infections and PNALT were categorized into immune tolerant (IT, n = 108), inactive HBV surface antigen (HBsAg) carrier (IHC, n = 61), GZ-1 (HBeAg positive in GZ, n = 92), and GZ-2 (HBeAg negative in GZ, n = 68) phases. Among them, 51.3% were in the GZ phase, and 50.1% presented with EHI. The IL-6 levels were higher in the EHI group than in the non-EHI group (2.77 vs. 1.53 pg/ml, Z = −13.32, p = 0.028). The monocyte chemoattractant protein 1 (MCP-1) level was positively correlated with HBV DNA (R = 0.64, p < 0.001) and HBeAg (R = 0.5, p < 0.001) but negatively correlated with fibrosis grade (R = −0.26, p = 0.048). The ratio of EHI in the GZ phase was 60.55%, which was significantly higher than that in patients in the IT (39.8%) and IHC phases (37.7%) (χ² = 10.4, p = 0.006). A total of 46.69% of all patients exceeded the new ALT antiviral treatment threshold (30 U/L for men and 19 U/L for women). The EHI values in the IT and IHC phases below the new ALT threshold were 32.6% and 37.8%, respectively, whereas higher EHI values of 67.4% and 68.4% were seen in GZ-1 and GZ-2 patients, respectively, exceeding the new ALT threshold, and the difference was statistically significant (χ² = 11.13, p < 0.001; χ² = 14.22, p = 0.002). The median age in our cohort was 38.91 years, and only 21.03% were less than 30 years old. The EHI values in the IT and IHC patients <30 years old were 32.4% and 35.8%, respectively, while the ratio of EHI increased to 43.2% once patients were older than 30 years but still in the IT and IHC stages.

Conclusion

Setting 30 years old as a cut-off and lowering the ALT threshold could facilitate screening for the presence of significant liver injury, especially for GZ patients. IL-6 was a good indicator of EHI, and MCP-1 was significantly positively correlated with HBV DNA but negatively correlated with liver fibrosis.

Polystyrene nanoparticle exposure supports ROS-NLRP3 axis-dependent DNA-NET to promote liver inflammation

The widespread use of plastics and the rapid development of nanotechnology bring convenience to our lives while also increasing the environmental burden and increasing the risk of exposure of organisms to nanoparticles (NPs). While recent studies have revealed an association between nanoparticles and liver injury, the intrinsic mechanism of NP exposure-induced liver damage remains to be explored. Here, we found that polystyrene nanoparticle (PSNP) exposure resulted in a significant increase in local neutrophil infiltration and neutrophil extracellular trap (NET) formation in the liver. Analysis of a coculture system of PBNs and AML12 cells revealed that PSNP-induced NET formation positively correlates with the reactive oxygen species (ROS)-NLRP3 axis. Inhibition of ROS and genetic and pharmacological inhibition of NLRP3 in AML12 can both alleviate PSNP-induced NET formation. In turn, exposure of mice to deoxyribonuclease I (DNase Ⅰ)-coated PSNPs disassembled NET in vivo, neutrophil infiltration in the liver was reduced, the ROS-NLRP3 axis was inhibited, and the expression of cytokines was markedly decreased. Collectively, our work reveals a mechanism of NET formation in PSNP exposure-induced liver inflammation and highlights the possible role of DNase Ⅰ as a key enzyme in degrading NET and alleviating liver inflammation.

Terlipressin use and respiratory failure in patients with hepatorenal syndrome type 1 and severe acute-on-chronic liver failure

BACKGROUND

Previous studies suggested increased mortality in patients with hepatorenal syndrome type 1 (HRS1) and advanced acute-on-chronic liver failure (ACLF).

AIM

To assess mortality and respiratory failure (RF) in patients with HRS1 and ACLF treated with terlipressin.

METHODS

In the CONFIRM study, we randomised 299 patients with HRS1 2:1 to terlipressin or placebo, both with albumin. At enrolment, all patients were assessed for organ failure (OF) using a validated ACLF grading system. Post hoc analyses assessed the effects of terlipressin vs. placebo on the incidence of RF and 90-day mortality.

RESULTS

The incidence of RF with terlipressin (n = 200) was 9.4% in patients with grades 1-2 ACLF, and 30% with grade 3 ACLF (p = 0.0002); no such difference was observed in placebo-treated patients (n = 99) (6.2% grades 1-2 vs. 0% grade 3 ACLF, p > 0.05). RF incidence between terlipressin and placebo in patients with grade 3 ACLF was significant (p = 0.01). Baseline predictors of RF with terlipressin were INR (p = 0.011), mean arterial pressure (p = 0.037), and SpO₂ (p = 0.014). Prior albumin as a continuous variable was not a predictor of RF. 90-day survival between terlipressin and placebo arms was similar for grades 1-2 ACLF (55.5% and 56.6%, respectively), but lower for grade 3 ACLF (27.55% vs. 50.0%) (p = 0.122), mainly related to RF.

CONCLUSION

Terlipressin should be used with caution in patients with HRS1 and grade 3 ACLF. Patients with hypoxaemia are at increased risk of RF and mortality.

The neutrophil-to-lymphocyte ratio represents a systemic inflammation marker and reflects the relationship with 90-day mortality in non-cirrhotic chronic severe hepatitis

OBJECTIVES

To investigate the relationship between systemic inflammatory response and short-term mortality in patients with non-cirrhotic chronic severe hepatitis (CSH) by using several indicators of inflammation including neutrophil-to-lymphocyte ratio (NLR), neutrophil (NEU), white blood cell (WBC), platelet-to lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR).

METHODS

Data were collected from two prospectively enrolled CATCH-LIFE noncirrhotic cohorts. Cox regression analysis was used to investigate the association between systemic inflammatory biomarkers and 90-day liver transplant (LT)-free mortality. A generalized additive model (GAM) was used to illustrate the quantitative curve relationship between NLR and 90-day LT-free mortality. Kaplan-Meier method was used to estimate the 90-year LT-free survival.

RESULTS

The prevalence of CSH was 20.5% (226/1103). The 28-day and 90-day LT-free mortality rates were 17.7% and 26.1%, respectively, for patients with non-cirrhotic CSH. Patients with no infection accounted for 75.0% of all CSH patients, and NLR was independently associated with 90-day LT-free mortality. NLR of 2.9 might be related to disease deterioration in CSH patients without infection.

CONCLUSIONS

NLR may be an independent risk factor for 90-day LT-free mortality in patients with non-cirrhotic chronic liver disease. A NLR of 2.9 as the cut-off value can be used to predict disease aggravation in CSH patients without infection.

Identification of effective diagnostic biomarker and immune cell infiltration characteristics in acute liver failure by integrating bioinformatics analysis and machine-learning strategies

Background: To determine effective biomarkers for the diagnosis of acute liver failure (ALF) and explore the characteristics of the immune cell infiltration of ALF.

Methods: We analyzed the differentially expressed genes (DEGs) between ALF and control samples in GSE38941, GSE62029, GSE96851, GSE120652, and merged datasets. Co-expressed DEGs (co-DEGs) identified from the five datasets were analyzed for enrichment analysis. We further constructed a PPI network of co-DEGs using the STRING database. Then, we integrated the two kinds of machine-learning strategies to identify diagnostic biomarkers of top hub genes screened based on MCC and Degree methods. And the potential diagnostic performance of the biomarkers for ALF was estimated using the AUC values. Data from GSE14668, GSE74000, and GSE96851 databases was performed as external verification sets to validate the expression level of potential diagnostic biomarkers. Furthermore, we analyzed the difference in the protein level of diagnostic biomarkers between normal and ALF mice models. Finally, we used CIBERSORT to estimate relative infiltration levels of 22 immune cell subsets in ALF samples and further analyzed the relationships between the diagnostic biomarkers and infiltrated immune cells.

Results: A total of 200 co-DEGs were screened. Enrichment analyses depicted that they are highly enriched in metabolism and matrix collagen production-associated processes. The top 28 hub genes were obtained by integrating MCC and Degree methods. Then, the collagen type IV alpha 2 chain (COL4A2) was regarded as the diagnostic biomarker and showed excellent specificity and sensitivity. COL4A2 also showed a statistically significant difference and excellent diagnostic effectiveness in the verification set. In addition, there was a significant upregulation in the COL4A2 protein level in ALF mice models compared with the normal group. CIBERSORT analysis showed that activated CD4 T cells, plasma cells, macrophages, and monocytes may be implicated in the progress of ALF. In addition, COL4A2 showed different degrees of correlation with immune cells.

Conclusion: In conclusion, COL4A2 may be a diagnostic biomarker for ALF, and immune cell infiltration may have important implications for the occurrence and progression of ALF.

Bioinformatics analyses of potential ACLF biological mechanisms and identification of immune-related hub genes and vital miRNAs

Acute-on-chronic liver failure (ACLF) is a critical and refractory disease and a hepatic disorder accompanied by immune dysfunction. Thus, it is essential to explore key immune-related genes of ACLF and investigate its mechanisms. We used two public datasets (GSE142255 and GSE168048) to perform various bioinformatics analyses, including WGCNA, CIBERSORT, and GSEA. We also constructed an ACLF immune-related protein-protein interaction (PPI) network to obtain hub differentially expressed genes (DEGs) and predict corresponding miRNAs. Finally, an ACLF rat model was established to verify the results. A total of 388 DEGs were identified in ACLF, including 162 upregulated and 226 downregulated genes. The enrichment analyses revealed that these DEGs were mainly involved in inflammatory-immune responses and biosynthetic metabolic pathways. Twenty-eight gene modules were obtained using WGCNA and the coral1 and darkseagreen4 modules were highly correlated with M1 macrophage polarization. As a result, 10 hub genes and 2 miRNAs were identified to be significantly altered in ACLF. The bioinformatics analyses of the two datasets presented valuable insights into the pathogenesis and screening of hub genes of ACLF. These results might contribute to a better understanding of the potential molecular mechanisms of ACLF. Finally, further studies are required to validate our current findings.