Intrahepatic macrophage reprogramming associated with lipid metabolism in hepatitis B virus-related acute-on-chronic liver failure.

BACKGROUND: Acute-on-chronic liver failure (ACLF) is a severe syndrome with high short-term mortality, but the pathophysiology still remains largely unknown. Immune dysregulation and metabolic disorders contribute to the progression of ACLF, but the crosstalk between immunity and metabolism during ACLF is less understood. This study aims to depict the immune microenvironment in the liver during ACLF, and explore the role of lipid metabolic disorder on immunity. METHODS: Single-cell RNA-sequencing (scRNA-seq) was performed using the liver non-parenchymal cells (NPCs) and peripheral blood mononuclear cells (PBMCs) from healthy controls, cirrhosis patients and ACLF patients. A series of inflammation-related cytokines and chemokines were detected using liver and plasma samples. The lipid metabolomics targeted free fatty acids (FFAs) in the liver was also detected. RESULTS: The scRNA-seq analysis of liver NPCs showed a significant increase of monocytes/macrophages (Mono/Mac) infiltration in ACLF livers, whereas the resident Kupffer cells (KCs) were exhausted. A characterized TREM2+ Mono/Mac subpopulation was identified in ACLF, and showed immunosuppressive function. Combined with the scRNA-seq data from PBMCs, the pseudotime analysis revealed that the TREM2+ Mono/Mac were differentiated from the peripheral monocytes and correlated with lipid metabolism-related genes including APOE, APOC1, FABP5 and TREM2. The targeted lipid metabolomics proved the accumulation of unsaturated FFAs associated with α-linolenic acid (α-LA) and α-LA metabolism and beta oxidation of very long chain fatty acids in the ACLF livers, indicating that unsaturated FFAs might promote the differentiation of TREM2+ Mono/Mac during ACLF. CONCLUSIONS: The reprogramming of macrophages was found in the liver during ACLF. The immunosuppressive TREM2+ macrophages were enriched in the ACLF liver and contributed to the immunosuppressive hepatic microenvironment. The accumulation of unsaturated FFAs in the ACLF liver promoted the reprogramming of the macrophages. It might be a potential target to improve the immune deficiency of ACLF patients through regulating lipid metabolism.

Liver cirrhosis and immune dysfunction.

Cirrhosis is end-stage liver disease resulting from various etiologies and is a common cause of death worldwide. The progression from compensated to decompensated cirrhosis to acute-on-chronic liver failure (ACLF) is due to multiple factors, including continuation of alcohol use or continued exposure to other toxins, an imbalance of the gut microbiota (dysbiosis), increased gut permeability and a disrupted immune response. This disrupted immune response is also named cirrhosis-associated immune dysfunction, which is characterized by worsening systemic inflammation with concomitant immune paralysis, as liver disease deteriorates. This review highlights central immunologic events during the exacerbation of cirrhosis and characterizes the different immune cell populations involved therein.

The clinical relevance of acute-on-chronic liver failure in medical procedures: Endoscopy, interventions and surgery.

Acute-on-chronic liver failure (ACLF) is a specific, but complex and multifactorial form of acute decompensation (AD) of cirrhosis and is characterized by an extraordinary dynamic natural course, rapidly evolving organ failure and high short-term mortality. In daily clinical practice, patients with liver cirrhosis and decompensation have indications for different medical procedures such as endoscopies, interventional treatments like transjugular intrahepatic portosystemic shunt (TIPS) or even surgical procedures. In these situations, clinicians often need to balance the expected benefits of such procedures with the risks of causing acute decompensation or ACLF. This review summarizes the evidence of medical procedures and their role in precipitating or preventing ACLF and highlights the aspects to consider during patient selection.

Exaggerated inflammatory response to bacterial products in decompensated cirrhotic patients is orchestrated by interferons IL-6 and IL-8.

Cirrhosis-associated immune dysfunction (CAID) contributes to disease progression and organ failure development. We interrogated immune system function in nonseptic compensated and decompensated cirrhotic patients using the TruCulture whole blood stimulation system, a novel technique that allows a more accurate representation than traditional methods, such as peripheral blood mononuclear cell culture, of the immune response in vivo. Thirty cirrhotics (21 decompensated and 9 compensated) and seven healthy controls (HCs) were recruited. Whole blood was drawn directly into three TruCulture tubes [unstimulated to preloaded with heat-killed Escherichia coli 0111:B4 (HKEB) or lipopolysaccharide (LPS)] and incubated in dry heat blocks at 37°C for 24 h. Cytokine analysis of the supernatant was performed by multiplex assay. Cirrhotic patients exhibited a robust proinflammatory response to HKEB compared with HCs, with increased production of interferon-γ-induced protein 10 (IP-10) and IFN-λ1, and to LPS, with increased production of IFN-λ1. Decompensated patients demonstrated an augmented immune response compared with compensated patients, orchestrated by an increase in type I, II, and III interferons, and higher levels of IL-1ß, IL-6, and IL-8 post-LPS stimulation. IL-1ß, TNF-α, and IP-10 post-HKEB stimulation and IP-10 post-LPS stimulation negatively correlated with biochemical markers of liver disease severity and liver disease severity scores. Cirrhotic patients exposed to bacterial products exhibit an exaggerated inflammatory response orchestrated by IFNs, IL-6, and IL-8. Poststimulation levels of a number of proinflammatory cytokines negatively correlate with markers of liver disease severity raising the possibility that the switch to an immunodeficient phenotype in CAID may commence earlier in the course of advanced liver disease. NEW & NOTEWORTHY Decompensated cirrhotic patients, compared with compensated patients, exhibit a greater exaggerated inflammatory response to bacterial products orchestrated by interferons, IL-6, and IL-8. Postbacterial product stimulation levels of a number of pro-inflammatory cytokines negatively correlate with liver disease severity biomarkers and liver disease severity scores raising the possibility that the switch to an immunodeficient phenotype in cirrhosis-associated immune dysfunction may commence earlier in the course of advanced liver disease.

Circulating extracellular vesicles induce monocyte dysfunction and are associated with sepsis and high mortality in cirrhosis.

BACKGROUND: Sepsis is common in cirrhosis and is often a result of immune dysregulation. Specific stimuli and pathways of inter-cellular communications between immune cells in cirrhosis and sepsis are incompletely understood. Immune cell-derived extracellular vesicles (EV) were studied to understand mechanisms of sepsis in cirrhosis. METHODS: Immune cell-derived EV were measured in cirrhosis patients [Child-Turcotte-Pugh (Child) score A, n = 15; B n = 16; C n = 43 and Child-C with sepsis (n = 38)], and healthy controls (HC, n = 11). In vitro and in vivo functional relevance of EV in cirrhosis and associated sepsis was investigated. RESULTS: Monocyte, neutrophil and hematopoietic stem cells associated EV progressively increased with higher Child score (P < .001)and correlated with liver disease severity indices (r2  > 0.3, P < .001), which further increased in Child C sepsis than without sepsis(P < .001); monocyte EV showing the highest association with disease stage [P = .013; Odds ratio-4.14(1.34-12.42)]. A threshold level of monocyte EV of 53/µl predicted mortality in patients of Child C with sepsis [Odds ratio-6.2 (2.4-15.9), AUROC = 0.76, P < .01]. In vitro EV from cirrhotic with sepsis compared without sepsis, induced mobilization arrest in healthy monocytes within 4 hours (P = .004), reduced basal oxygen consumption rate (P < .001) and induced pro-inflammatory genes (P < .05). The septic-EV on adoptive transfer to C57/BL6J mice, induced sepsis-like condition within 24 h with leukocytopenia (P = .005), intrahepatic inflammation with increased CD11b + cells (P = .03) and bone marrow hyperplasia (P < .01). CONCLUSION: Extracellular vesicles induce functional impairment in circulating monocytes and contribute to the development and perpetuation of sepsis. High levels of monocyte EV correlate with mortality and can help early stratification of sicker patients.

Immune dysfunction in cirrhosis: Distinct cytokines phenotypes according to cirrhosis severity.

BACKGROUND/OBJECTIVES: Cirrhosis associated immune dysfunction has been proposed to switch from a pro-inflammatory phenotype in stable cirrhosis to an immunodeficient one in patients with decompensated cirrhosis and acute-on-chronic liver failure. The aim of the present study was to compare serum cytokine levels between healthy patients, stable cirrhosis, and decompensated cirrhotic patients with and without development of acute-on-chronic liver failure (ACLF); and to explore whether any of the measured cytokines is associated with cirrhosis severity and prognosis in ACLF patients. METHODS: Patients were enrolled from October 2013 to May 2014 in two hospitals located in Buenos Aires. Cirrhotic patients with an acute decompensating event were enrolled accordingly to the development of ACLF defined by the CANONIC study group. There were two control groups: healthy subjects (n=14) and stable cirrhotic patients (n=14). Demographic, clinical and biochemical data were obtained. Seventeen cytokines were measured using Bio-Plex Pro Human Cytokine 17-plex Assay. RESULTS: Of the 49 decompensated cirrhotic patients enrolled, 18 (36.7%) developed ACLF. Leukocyte count, MELD score at admission, Clif-SOFA at admission and day 7 were significantly higher in the ACLF group (p=0.046, p<0.001, p<0.001, p<0.001 respectively) as well as short-term mortality (p<0.001) compared to stable and decompensated cirrhotic patients. In comparison with healthy controls, stable cirrhotic and decompensated cirrhotic patients showed increased levels of pro-inflammatory and anti-inflammatory cytokines: IL-6, IL-7, IL-8, IL-10, IL 12, and TNF-α. Decompensated cirrhotic patients with the development of ACLF showed a significant decrease of IL-7, IL-10, IL-12, TNF-α, MCP-1 and IFN-γ, but a sustained response of IL-6 and IL-8. When evaluating cirrhosis severity, IL-6 and IL-8 correlated positively with MELD score, whereas only IL-6 correlated positively with Clif-SOFA score at day 7; IL-2 correlated negatively with Clif-SOFA at admission. In comparison with all scores, leukocyte count showed positive correlation and IFN-γ negative correlation with disease severity. When evaluating survival, only MELD and Clif-SOFA scores had a significant association with mortality. CONCLUSIONS: Pro-inflammatory cytokines and chemo-attractant elements are increased in cirrhosis in comparison with healthy subjects, and display higher values concomitantly with cirrhosis progression. However, in acute-on-chronic liver failure an opposite cytokine pattern that can be resumed as a combination of immune paresis and excessive inflammatory response was observed. Several pro-inflammatory cytokines (IL-2, IL-6, IL-8 and IFN-γ) showed correlation with disease severity; their utility as prognostic biomarkers needs to be further studied.

Prevalence of human herpesvirus in plasma and saliva of cirrhotic patients: A pilot study.

AIMS: The objective of this study was to identify the presence of human herpesvirus (HHV) in the plasma and saliva of hepatic-cirrhosis patients and correlate it with clinical data and laboratory tests. This is a pilot, observational, and cross-sectional study. METHODS AND RESULTS: Specimens of plasma and saliva from 72 cirrhotic individuals were analyzed by means of polymerase chain reaction. The patient population had a mean age of 54.84 years old (SD ± 10) and was 70% males (51/72). Approximately 47% (n = 34) of the patients had leukopenia and HHV was not identified in the plasma specimens. The main species of HHV identified in the saliva were HHV-7 (n = 42, 62%) and Epstein-Barr virus (EBV) (n = 30, 41%). Moreover, there was a significant decrease in the total number of leukocytes and lymphocytes in saliva containing EBV (P = .038 and P = .047, respectively). CONCLUSION: The results show that the presence of EBV in the saliva of cirrhotic patients was correlated with their circulating immune status. It may be possible that the immune dysfunction displayed by the cirrhotic patients plays a role in the shedding of EBV into saliva.

Fatal Disseminated Coccidioidomycosis in Cirrhosis: A Case Series.

PURPOSE: Coccidioidomycosis is endemic to the Southwest United States and Mexico. In this case series we describe 3 cases, occurring in the Southwest United States, of patients with disseminated coccidioidomycosis infection in cirrhosis, all with a miliary pattern present on chest imaging. METHODS: This case series was performed conducting a review of patients' electronic health records and thorough review of the literature for coccidioidomycosis infection in patients with liver disease. RESULTS: Three patients with different etiology of liver disease with Model for End-stage Liver Disease - Sodium (MELD-Na) scores >20 had chest imaging findings indicative of a miliary pattern on presentation. Each patient subsequently had extensive infectious disease workup that showed evidence of disseminated coccidioidomycosis. All 3 patients clinically worsened and eventually died. CONCLUSIONS: This case series highlights the severity of disseminated coccidioidomycosis in patients with cirrhosis in an endemic area, as well as potential early clues such as miliary patterns on chest imaging. A review of the literature found a significant connection among potential mechanisms describing why patients with cirrhosis have such adverse outcomes in the setting of disseminated coccidioidomycosis, including cirrhosis-associated immune dysfunction and genetic defects in immune functioning.

Is the SIRS Criteria a Good Predictor of Blood stream Infection in Cirrhosis? A Single-Center Retrospective Analysis.

Introduction: Cirrhosis-associated immune dysfunction (CAID) is a chronic vasodilatory state with hyperdynamic circulation and alterations in thermoregulation that may make patients more susceptible to and mask underlying infection. This study aims to determine whether SIRS criteria are an accurate tool for predicting bloodstream infection (BSI) in cirrhosis. Methods: In our retrospective chart review, study population included patients with cirrhosis that were 18 years or older. For all study patients, model for end-stage liver disease (MELD) scores and values for each SIRS variable at the time of admission and blood culture data were recorded. Univariable and multivariable logistic regression analysis was performed to identify any associations between dichotomized SIRS variables that fulfill SIRS positivity and BSI. Results: Significantly more patients without BSI met positivity criteria for WBC counts (30% vs 13% p < .001). In the analysis of the SIRS variables as continuous variables in prediction of BSI, the AUC curves generated were all unsatisfactory with the temperature (36-38°C) and WBC count (4 × 103 to 12 × 103 mcL) at the time of admission having the highest areas under the ROC curve (0.52 and 0.55, respectively). Looking at the SIRS variables dichotomized (according to whether fulfilling SIRS criteria or not) in univariable logistic regression, only WBC counts meeting SIRS criteria were significantly associated with BSI OR 0.37 (0.18-0.77); p = .008, but this was an inverse association. This association was true even in the multivariable model OR 0.38 (0.18-0.80); p = .01. Conclusion: Our study shows that SIRS criteria are a poor predictor of BSI among patients with cirrhosis.

Quantification of Torque Teno Virus (TTV) in plasma and saliva of individuals with liver cirrhosis: a cross sectional study.

Introduction: Torque teno virus (TTV) has been pointed as an endogenous marker of immune function, the objective of this study was to investigate the TTV viral load in plasma and saliva of cirrhotic individuals and correlate it with clinical characteristics. Methods: Blood, saliva, clinical data from records and laboratory tests were collected from 72 cirrhotic patients. Plasma and saliva were submitted to real-time polymerase chain reaction for quantification of TTV viral load. Results: The majority of the patients presented decompensated cirrhosis (59.7%) and 47.2% had alterations in the white blood series. TTV was identified in 28 specimens of plasma (38.8%) and in 67 specimens of saliva (93.0%), with median values of TTV copies/mL of 90.6 in plasma and 245.14 in saliva. All the patients who were positive for TTV in plasma were also positive in saliva, with both fluids having a moderately positive correlation for the presence of TTV. There was no correlation between TTV viral load, either in plasma or in saliva, and any of the variables studied. Conclusion: TTV is more frequently found and in greater amount in the saliva than in the plasma of cirrhotic patients. There was no correlation between TTV viral load and clinical parameters.

The efficacy of branched-chain amino acid granules to restore phagocytic activity in cirrhosis patients, a randomized controlled trial.

Background: Infection is a detrimental complication among cirrhotic patients, leading to major morbidity and mortality. Reduction in phagocytic activation, as part of immunoparesis, is a distinctive key component of cirrhosis-associated immune dysfunction (CAID) and predicts the development of infection. However, there are limited data on immunotherapeutic approaches to restore phagocytosis. Aims: We aimed to determine the effect of branched-chain amino acid (BCAA) granules on phagocytic activity in patients with CAID. Methods: In this double-blind randomized controlled trial, Participants were randomly assigned (1:1 ratio stratified by Child-Pugh status) to receive either BCAA granules or placebo. In the 3rd and 6th months, phagocytic activity was assessed by flow cytometry. The primary endpoint was the restoration of innate immunity at the 6th month, defined as ≥75% phagocytic activity; the secondary endpoints were the accretion of phagocytic activity and hospitalization due to infection. Results: A total of 37 patients were included. There were no differences among the patients in the baseline characteristics and phagocytic activity. At the 6th month, a higher proportion of patients with phagocytic restoration was observed in the BCAA granule group compared to the placebo group (68 vs. 5.6%, p < 0.001). The mean phagocytic activity was 75.4 and 63.4% in the BCAA granule and placebo groups, respectively (p < 0.001). Progressive accretion of phagocytic activity was observed during the 3rd and 6th months. There was no difference in hospitalization due to infection (3 vs. 2 events, p = 0.487). Conclusion: Our results suggest that BCAA granules significantly restore phagocytic activity across various stages of cirrhosis. A longer follow-up period is required to demonstrate infection prevention.Clinical Trial Registration: www.clinicaltrials.in.th, TCTR20190830005.

Recompensation in Cirrhosis: Current Evidence and Future Directions.

The natural history of cirrhosis has usually been conceptualized in the context of progression from compensated cirrhosis to subsequent stages of decompensation. While this unidirectional concept is the most common pathophysiological trajectory, there has been an emerging understanding of a subgroup of patients which undergo recompensation. While literature mostly based on transplant waitlist registries have indicated towards such a population who experience disease regression, the overall literature about this entity remains inexplicit. An effort to generate consensus on defining recompensation has been attempted which comes with its own nuances and limitations. We summarize the available literature on this emerging yet controversial concept of recompensation in cirrhosis and delve into future implications and impact on real-life practice.

Impaired SARS-CoV-2-specific T-cell reactivity in patients with cirrhosis following mRNA COVID-19 vaccination.

Background & Aims: Cirrhosis entails elevated risk of COVID-19-associated mortality. This study determined T cell-mediated and antibody reactivity against the spike 1 (S1) protein of SARS-CoV-2 among 48 patients with cirrhosis and 39 healthy controls after mRNA COVID-19 vaccination. Methods: SARS-CoV-2-specific T-cell reactivity was measured by induced level of T cell-derived interferon-γ (IFN-γ) in blood cells stimulated ex vivo with multimeric peptides spanning the N-terminal portion of S1. S1-induced IFN-γ was quantified before and after the 1st and 2nd vaccination (BNT162b2, Pfizer-BioNTech or mRNA-1273, Moderna) alongside serum IgG against the receptor-binding domain (RBD) within S1 (anti-RBD-S1 IgG). Results: T-cell reactivity against S1 was reduced in patients with cirrhosis after the 1st (p <0.001 vs. controls) and 2nd (p <0.001) vaccination. Sixty-eight percent of patients lacked detectable S1-specific T-cell reactivity after the 1st vaccination vs. 19% in controls (odds ratio 0.11, 95% CI 0.03-0.48, p = 0.003) and 36% remained devoid of reactivity after the 2nd vaccination vs. 6% in controls (odds ratio 0.12, 95% CI 0.03-0.59, p = 0.009). T-cell reactivity in cirrhosis remained significantly impaired after correction for potential confounders in multivariable analysis. Advanced cirrhosis (Child-Pugh class B) was associated with absent or lower T-cell responses (p <0.05 vs. Child-Pugh class A). The deficiency of T-cell reactivity was paralleled by lower levels of anti-RBD-S1 IgG after the 1st (p <0.001 vs. controls) and 2nd (p <0.05) vaccination. Conclusions: Patients with cirrhosis show deficient T-cell reactivity against SARS-CoV-2 antigens along with diminished levels of anti-RBD-S1 IgG after dual COVID-19 vaccination, highlighting the need for vigilance and additional preventative measures. Clinical trial registration: EudraCT 2021-000349-42. Lay summary: T cells are a pivotal component in the defence against viruses. We show that patients with cirrhosis have impaired SARS-CoV-2-specific T-cell responses and lower antibody levels after mRNA vaccination against COVID-19 compared with healthy controls. Patients with more advanced liver disease exhibited particularly inferior vaccine responses. These results call for additional preventative measures in these patients.

Monocyte dysfunction in decompensated cirrhosis is mediated by the prostaglandin E2-EP4 pathway.

BACKGROUND & AIMS: Infection is a major problem in advanced liver disease secondary to monocyte dysfunction. Elevated prostaglandin (PG)E2 is a mediator of monocyte dysfunction in cirrhosis; thus, we examined PGE2 signalling in outpatients with ascites and in patients hospitalised with acute decompensation to identify potential therapeutic targets aimed at improving monocyte dysfunction. METHODS: Using samples from 11 outpatients with ascites and 28 patients hospitalised with decompensated cirrhosis, we assayed plasma levels of PGE2 and lipopolysaccharide (LPS); performed quantitative real-time PCR on monocytes; and examined peripheral blood monocyte function. We performed western blotting and immunohistochemistry for PG biosynthetic machinery expression in liver tissue. Finally, we investigated the effect of PGE2 antagonists in whole blood using polychromatic flow cytometry and cytokine production. RESULTS: We show that hepatic production of PGE2 via the cyclo-oxygenase 1-microsomal PGE synthase 1 pathway, and circulating monocytes contributes to increased plasma PGE2 in decompensated cirrhosis. Transjugular intrahepatic sampling did not reveal whether hepatic or monocytic production was larger. Blood monocyte numbers increased, whereas individual monocyte function decreased as patients progressed from outpatients with ascites to patients hospitalised with acute decompensation, as assessed by Human Leukocyte Antigen (HLA)-DR isotype expression and tumour necrosis factor alpha and IL6 production. PGE2 mediated this dysfunction via its EP4 receptor. CONCLUSIONS: PGE2 mediates monocyte dysfunction in decompensated cirrhosis via its EP4 receptor and dysfunction was worse in hospitalised patients compared with outpatients with ascites. Our study identifies a potential drug target and therapeutic opportunity in these outpatients with ascites to reverse this process to prevent infection and hospital admission. LAY SUMMARY: Patients with decompensated cirrhosis (jaundice, fluid build-up, confusion, and vomiting blood) have high infection rates that lead to high mortality rates. A white blood cell subset, monocytes, function poorly in these patients, which is a key factor underlying their sensitivity to infection. We show that monocyte dysfunction in decompensated cirrhosis is mediated by a lipid hormone in the blood, prostaglandin E2, which is present at elevated levels, via its EP4 pathway. This dysfunction worsens when patients are hospitalised with complications of cirrhosis compared with those in the outpatients setting, which supports the EP4 pathway as a potential therapeutic target for patients to prevent infection and hospitalisation.

Propranolol Suppresses the T-Helper Cell Depletion-Related Immune Dysfunction in Cirrhotic Mice.

Bacterial translocation (BT) and splenomegaly contribute to cirrhosis-associated immune dysfunction (CAID) including T cell depletion, infection, and chronic inflammation. ß-blockers have been reported to decrease BT and improve splenomegaly. This study explores the modulation of ß1 and ß2 adrenergic receptors (ADRB1/ADRB2) by propranolol treatment on the peripheral and splenic immune dysfunction of cirrhotic mice. In vivo experiments were performed in bile duct ligation (BDL)- and thioacetamide (TAA)-cirrhotic mice receiving two weeks of propranolol treatment. Acute effects of propranolol were evaluated in T-helper (Th) cells isolated from spleen of cirrhotic mice. Over-expression of ß1 and ß2 adrenergic receptors (ADRB1/ADRB2) in spleen and T lymphocytes was associated with high peripheral/splenic lipopolysaccharide binding protein levels. Moreover, a decrease in Th cells percentage, increase in Treg subset, and cytokines were accompanied by increased apoptosis, proliferation, and reduced white pulp hyperplasia in cirrhotic mice, which were counteracted by propranolol treatment. The Th-cell depletion, systemic inflammation, BT, and infection were improved by chronic propranolol treatment. Acute propranolol treatment inhibited apoptosis, Treg-conditioned differentiation, and promoted Th2-conditioned differentiation through ADRB-cyclic adenosine monophosphate (cAMP) signals in cirrhotic mice. In conclusion, suppression of ADRB1 and ADRB2 expressions in spleen and splenic T lymphocytes by acute and chronic propranolol treatment ameliorate systemic and splenic immune dysfunction in cirrhosis.

Dysfunctional Immune Response in Acute-on-Chronic Liver Failure: It Takes Two to Tango.

Acute-on-chronic liver failure (ACLF) is characterized by the acute decompensation of cirrhosis associated with organ failure and high short-term mortality. The key event in the pathogenesis is a dysfunctional immune response arising from exacerbation of the two main immunological alterations already present in cirrhosis: systemic inflammation and immune cell paralysis. High-grade systemic inflammation due to predominant activation and dysregulation of the innate immune response leads to the massive release of cytokines. Recognition of acutely increased pathogen and damage-associated molecular patterns by specific receptors underlies its pathogenesis and contributes to tissue damage and organ failure. In addition, an inappropriate compensatory anti-inflammatory response over the course of ACLF, along with the exhaustion and dysfunction of both the innate and adaptive immune systems, leads to functional immune cell paralysis. This entails a high risk of infection and contributes to a poor prognosis. Therapeutic approaches seeking to counteract the immune alterations present in ACLF are currently under investigation.

CD8+T cells from patients with cirrhosis display a phenotype that may contribute to cirrhosis-associated immune dysfunction.

BACKGROUND: Cirrhosis-associated immune dysfunction (CAID) contributes to high sepsis risk in patients with chronic liver disease. Various innate and; to a lesser extent; adaptive immune dysfunctions have been described as contributors to CAID leading to immune-paresis and impaired anti-microbial response in cirrhosis. In this study, we examined the phenotype of CD8+T cells in chronic liver disease with the aim to evaluate changes that might contribute to impaired immune responses. METHODS: Sixty patients with cirrhosis were prospectively recruited for this study. CD8+T cells from peripheral blood, ascites and liver explants were characterized using flow cytometry and immunohistochemistry, respectively. The transcriptional signature of flow-sorted HLA-DR+CD8+T cells was performed using Nanostring™ technology. HLA-DR+CD8+T cells interactions with PBMCs and myeloid cells were tested in vitro. FINDINGS: Peripheral CD8+T cells from cirrhotic patients displayed an altered phenotype characterized by high HLA-DR and TIM-3 surface expression associated with concomitant infections and disease severity, respectively. Paired peritoneal CD8+T cells expressed more pronounced levels of HLA-DR and PD-1 compared to peripheral CD8+T cells. HLA-DR+CD8+T cells were enriched in cirrhotic livers compared to controls. TIM-3, CTLA-4 and PD-1 levels were highly expressed on HLA-DR+CD8+T cells and co-expression of HLA-DR and PD1 was higher in patients with poor disease outcomes. Genes involved in cytokines production and intracellular signalling pathways were strongly down-regulated in HLA-DR+CD8+T cells. In comparison to their HLA-DR- counterparts, HLA-DR+CD8+T cells promoted less proliferation of PBMCs and induced phenotypic and functional dysfunctions in monocytes and neutrophils in vitro. INTERPRETATION: In patients with cirrhosis, CD8+T cells display a phenotypic, functional and transcriptional profile which may contribute to CAID. FUND: This work was supported by Medical Research Council, the Rosetrees Charitable Trust, Robert Tournut 2016 grant (Sociéte Nationale Française de GastroEntérologie), Gilead® sciences, and NIHR Imperial Biomedical Research Centre.

Hyperactive Follicular Helper T Cells Contribute to Dysregulated Humoral Immunity in Patients With Liver Cirrhosis.

Objectives: Liver cirrhosis (LC) is usually accompanied by cirrhosis associated immune dysfunction (CAID), including reduced naïve T cells and memory B cells. However, little is known regarding on follicular helper T (Tfh) cell compartments in cirrhotic patients, especially in the secondary lymphoid organs such as spleen. This study characterizes splenic Tfh cells and explores its association with humoral immunity and disease progression in cirrhotic patients. Methods: Using flow cytometry and histological staining, we analyzed the frequency and cytokine production of splenic Tfh cells from LC patients and healthy controls (HCs). Co-culture experiments of sorted Tfh and B cells were performed for functional analysis in vitro. The correlations between Tfh cells and disease progression markers as well as B cell subset perturbations were also examined. Results: PD-1highICOS+CXCR5+ Tfh cells were preferentially enriched in the spleen of cirrhotic patients, where they expressed higher levels of CXCR3 and produced more interleukin (IL)-21. Histologically, more splenic Tfh cells occupied the B cell follicular structure in LC patients where they shaped more active germinal centers (GCs) than those in HC spleens. In vitro, splenic Tfh cells in cirrhotic patients robustly induce plasma cell differentiation through IL-21 dependent manner. Finally, increased Tfh cell frequency is positively correlated with the plasma cells and disease severity in LC patients. Conclusions: We conclude that hyperactive Tfh cells contribute to dysregulated humoral immunity in patients with liver cirrhosis.

Infections in Liver Disease.

Infectious complications are common occurrences in end-stage liver disease (ESLD). Frequent infections precipitate decompensation of liver disease leading to acute or chronic liver failure, organ dysfunction, de-listing from transplant, and major morbidity and mortality. The spectrum of microorganisms has shifted with the emergence of multidrug-resistant strains, which has major implications for both therapy and prophylaxis. Cirrhosis is often associated with an underlying noninfectious systemic inflammatory state that makes diagnosis of infections particularly challenging. Adequate resuscitation and timely administration of appropriate antibiotics are pivotal to improved outcomes from infections in ESLD.