Defective thymopoiesis and poor peripheral homeostatic replenishment of T-helper cells cause T-cell lymphopenia in cirrhosis

Hospital Mortality in Acute Decompensation of Alcoholic Liver Cirrhosis: Can Novel Survival Markers Outperform Traditional Ones?

Background: There is a strong correlation between systemic inflammation intensity and clinical presentation, disease progression, and survival during liver cirrhosis decompensation. This study aimed to evaluate the prognostic performance of blood-based biomarkers as meta-inflammation markers, including NLR, PLR, LMR, INPR, MPR, ALBI, FIB4, and APRI, in predicting hospital mortality in patients with acute decompensation of alcohol-related liver cirrhosis. Methods: Data from 411 patients with their first onset of acute decompensation were analyzed, forming two groups: deceased and survived during hospitalization. Generalized partial least squares regression analysis was applied to explore the effects of surrogate indicators on mortality rates, using mortality rate as the dependent variable. Root Mean Square Error, Akaike's, and Bayesian information criteria determined that four components accounted for most of the variance. Results: Variables with significant negative contributions to the outcome prediction (ranked by standardized regression coefficients) were encephalopathy grade, total bilirubin, Child-Turcotte-Pugh score, MELD, NLR, MPV, FIB4, INR, PLR, and ALT. Coefficient sizes ranged from -0.63 to -0.09, with p-values from 0 to 0.018. Conclusions: NLR, PLR, and FIB4 significantly contribute to hospital mortality prediction in patients with acute decompensation of alcohol-related liver cirrhosis. Conversely, some variables used to predict liver disease severity, including INPR, APRI, LMR, and ALBI score, did not significantly contribute to hospital mortality prediction in this patient population.

Liver cirrhosis is a risk-factor for Pneumocystis jirovecii associated mortality

Background

Pneumocystis jirovecci pneumonia (PCP) is a life threating disease in immunodeficient patients. Liver cirrhosis itself can lead to immunodefiency, however little is known if Pneumocystis jirovecci infection affects the outcome of patients with liver cirrhosis.

Aim

We aimed to assess the predictors for Pneumocystis jirovecci-associated mortality in patients with Pneumocystis jirovecci infection treated at intensive care units.

Methods

A total of 151 patients hospitalized between January 2013 and November 2019 with a PCR-confirmed Pneumocystis jirovecci infection were retrospectively included in this study and analysed for clinical predictors for PCJ associated mortality.

Results

The overall mortality in our patient cohort was 60%. Out of 151 patients included in the analysis, 67 (44%) patients suffered from liver cirrhosis. Patients with an advanced liver cirrhosis (Child-Pugh class C) showed the highest mortality rate of 84.7%. The presence of a liver cirrhosis was associated with a significant increased risk of mortality (OR: 4.809) ([95%-CI: 2.32-9.97]; p < 0.001). There was a significant correlation of Meld score and mortality (r = 0.612, p < 0.001).

Discussion

To our knowledge, this study represents the largest evaluation of Pneumocystis jirovecci infection in patients with advanced liver cirrhosis. Cirrhosis associated immune dysfunction (CAID) describes the spectrum of immunological disturbances in patients with cirrhosis, which is linked to a heightened vulnerability to bacterial infections. Our data indicate a heightened susceptibility to fungal infections. Understanding the phenotypic manifestations of CAID could lead to immune-targeted therapies aimed at reducing infection susceptibility and decreasing CAID-associated mortality in cirrhosis patients.

Liver Cirrhosis: The Immunocompromised State

Systemic inflammation and immunodeficiency are important components of cirrhosis-associated immune dysfunction (CAID), the severity of which is dynamic, progressive, and associated with the greater deterioration of liver function. Two inflammation phenotypes have been described: low-grade and high-grade systemic inflammation. Both of these phenotypes are related to liver cirrhosis function; thus, high-grade inflammation is correlated with the severity of hepatic insufficiency, bacterial translocation, and organic insufficiency, with which the risk of infections increases and the prognosis worsens. Bacterial translocation (BT) plays a relevant role in persistent systemic inflammation in patients with cirrhosis, and the prophylactic employment of antibiotics is useful for reducing events of infection and mortality.

Wilson's Disease-Crossroads of Genetics, Inflammation and Immunity/Autoimmunity: Clinical and Molecular Issues

Wilson's disease (WD) is a rare, autosomal recessive disorder of copper metabolism caused by pathogenic mutations in the ATP7B gene. Cellular copper overload is associated with impaired iron metabolism. Oxidative stress, cuproptosis, and ferroptosis are involved in cell death in WD. The clinical picture of WD is variable. Hepatic/neuropsychiatric/other symptoms may manifest in childhood/adulthood and even old age. It has been shown that phenotypic variability may be determined by the type of ATP7B genetic variants as well as the influence of various genetic/epigenetic, environmental, and lifestyle modifiers. In 1976, immunological abnormalities were first described in patients with WD. These included an increase in IgG and IgM levels and a decrease in the percentage of T lymphocytes, as well as a weakening of their bactericidal effect. Over the following years, it was shown that there is a bidirectional relationship between copper and inflammation. Changes in serum cytokine concentrations and the relationship between cytokine gene variants and the clinical course of the disease have been described in WD patients, as well as in animal models of this disease. Data have also been published on the occurrence of antinuclear antibodies (ANAs), antineutrophil cytoplasmic antibodies (ANCAs), anti-muscle-specific tyrosine kinase antibodies, and anti-acetylcholine receptor antibodies, as well as various autoimmune diseases, including systemic lupus erythematosus (SLE), myasthenic syndrome, ulcerative colitis, multiple sclerosis (MS), polyarthritis, and psoriasis after treatment with d-penicillamine (DPA). The occurrence of autoantibodies was also described, the presence of which was not related to the type of treatment or the form of the disease (hepatic vs. neuropsychiatric). The mechanisms responsible for the occurrence of autoantibodies in patients with WD are not known. It has also not been clarified whether they have clinical significance. In some patients, WD was differentiated or coexisted with an autoimmune disease, including autoimmune hepatitis or multiple sclerosis. Various molecular mechanisms may be responsible for immunological abnormalities and/or the inflammatory processes in WD. Their better understanding may be important for explaining the reasons for the diversity of symptoms and the varied course and response to therapy, as well as for the development of new treatment regimens for WD.

Single-cell sequencing and multiple machine learning algorithms to identify key T-cell differentiation gene for progression of NAFLD cirrhosis to hepatocellular carcinoma

Introduction: Hepatocellular carcinoma (HCC), which is closely associated with chronicinflammation, is the most common liver cancer and primarily involves dysregulated immune responses in the precancerous microenvironment. Currently, most studies have been limited to HCC incidence. However, the immunopathogenic mechanisms underlying precancerous lesions remain unknown. Methods: We obtained single-cell sequencing data (GSE136103) from two nonalcoholic fatty liver disease (NAFLD) cirrhosis samples and five healthy samples. Using pseudo-time analysis, we systematically identified five different T-cell differentiation states. Ten machine-learning algorithms were used in 81 combinations to integrate the frameworks and establish the best T-cell differentiation-related prognostic signature in a multi-cohort bulk transcriptome analysis. Results: LDHA was considered a core gene, and the results were validated using multiple external datasets. In addition, we validated LDHA expression using immunohistochemistry and flow cytometry. Conclusion: LDHA is a crucial marker gene in T cells for the progression of NAFLD cirrhosis to HCC.

Vaccine Responses in Patients with Liver Cirrhosis: From the Immune System to the Gut Microbiota

Vaccines prevent a significant number of deaths annually. However, certain populations do not respond adequately to vaccination due to impaired immune systems. Cirrhosis, a condition marked by a profound disruption of immunity, impairs the normal immunization process. Critical vaccines for cirrhotic patients, such as the hepatitis A virus (HAV), hepatitis B virus (HBV), influenza, pneumococcal, and coronavirus disease 19 (COVID-19), often elicit suboptimal responses in these individuals. The humoral response, essential for immunization, is less effective in cirrhosis due to a decline in B memory cells and an increase in plasma blasts, which interfere with the creation of a long-lasting response to antigen vaccination. Additionally, some T cell subtypes exhibit reduced activation in cirrhosis. Nonetheless, the persistence of memory T cell activity, while not preventing infections, may help to attenuate the severity of diseases in these patients. Alongside that, the impairment of innate immunity, particularly in dendritic cells (DCs), prevents the normal priming of adaptive immunity, interrupting the immunization process at its onset. Furthermore, cirrhosis disrupts the gut-liver axis balance, causing dysbiosis, reduced production of short-chain fatty acids (SCFAs), increased intestinal permeability, and bacterial translocation. Undermining the physiological activity of the immune system, these alterations could impact the vaccine response. Enhancing the understanding of the molecular and cellular factors contributing to impaired vaccination responses in cirrhotic patients is crucial for improving vaccine efficacy in this population and developing better prevention strategies.

Humoral and cellular immune response in patients of liver cirrhosis and immunocompetent recipient of ChAdOx1nCoV-19 Vaccine (Covishield)

Despite the effectiveness of COVID-19 vaccination in reducing the severity of the disease, the demand for booster is increasing in vulnerable populations like elderly and immunocompromised individuals especially with each new wave of COVID-19 in different countries. There is limited data on the sustained immunity against COVID-19 in patients with liver cirrhosis. The study was aimed to compare the T cell and humoral immune response after 1 year of ChAdOx1nCoV-19 Vaccine in patients with liver cirrhosis and healthy health care workers (HCW). This was a prospective observational study including 36 HCW, 19 liver cirrhosis patients and 10 unvaccinated individuals. Anti-SARS-CoV-2S antibody, neutralizing antibody and memory T cell subsets were evaluated by ELISA and flow cytometry, respectively, in all three groups after 1 year of initial vaccination. Compared to HCW and unvaccinated individuals, liver cirrhosis patients had significantly depleted T cells, although CD4:CD8 + T cell ratio was normal. Both cirrhotic patients and HCW developed memory T cell subset [effector memory RA (P = 0.141, P < 0.001), effector memory (P < 0.001, P < 0.001), central memory (P < 0.001, P < 0.01), stem cell memory (P = 0.009, P = 0.08) and naïve (P < 0.001, P = 0.02)] compared to unvaccinated unexposed individuals of CD4 + T and CD8 + T, respectively. However, among HCW and cirrhotic group no difference was noted on central memory and stem cell memory cells on T cells. Patients with liver cirrhosis developed comparable memory T cells after vaccination which can evoke sustainable immune response on reinfection. Therefore, additional vaccine doses may not be necessary for cirrhosis patients.

Liver Cirrhosis Increases the Risk of Herpes Zoster: A Nationwide Population-Based Cohort Study

INTRODUCTION

Limited data are available regarding the association between liver cirrhosis (LC) and the risk of herpes zoster (HZ). This study aimed to determine the risk of HZ in patients with LC.

METHODS

HZ was defined as the presence of the International Classification of Diseases-10th revision code for HZ and concomitant prescription of antiviral medication. The incidence rates and standardized incidence ratios (SIRs) of HZ in patients with LC were analyzed using data from the Health Insurance Review and Assessment Service in Korea claims database from 2009 to 2019.

RESULTS

A total of 504,986 Korean patients with LC were included. The mean age was 52.4 years, and 60.8% were men. Chronic hepatitis B was the most common cause of LC. The incidence rates for HZ and HZ-related hospitalization were 21.6 of 1,000 and 1.81 of 1,000 person-years, respectively. The SIRs for HZ and HZ-related hospitalization were 1.09 (95% confidence interval [CI]: 1.08-1.09) and 1.48 (95% CI: 1.44-1.52), respectively, which were significantly higher than those in the general population. Patients with LC aged 20-29, 30-39, and 40-49 years had SIRs for HZ of 1.41 (95% CI: 1.33-1.48), 1.16 (1.13-1.19), and 1.17 (1.13-1.19), respectively. In multivariable analysis, woman (adjusted hazard ratio [AHR]: 1.48), steroid (AHR: 1.20), immunosuppressant use (AHR: 1.26), and combined comorbidities were associated with an increased risk of HZ among patients with LC.

DISCUSSION

Patients with LC, particularly those who are not currently recommended for HZ vaccination, were at an increased risk of HZ and HZ-related hospitalization compared with the general Korean population.

Dysfunctions of Circulating Adaptive Immune Cells in End-Stage Liver Disease

End-stage liver disease (ESLD) from acute liver failure to compensated advanced chronic liver disease and decompensated cirrhosis at different stages (chronic decompensation, acute decompensation with or without acute-on-chronic liver failure) has high disease severity and poor patient outcome. Infection is a common complication in patients with ESLD and it is associated with a high mortality rate. Multiple mechanisms are involved in this marked susceptibility to infections, noticeably the inadequate immune response known as immune paresis, as part of cirrhosis-associated immune dysfunction (CAID). Specifically in the adaptive immune arm, lymphocyte impairments—including inadequate activation, reduced ability to secrete effector molecules and enhanced immune suppressive phenotypes—result in compromised systemic immune responses and increased risk of infections. This review summarises current knowledge of alterations in adaptive immune responsiveness and their underlying mechanisms in ESLD. Understanding these mechanisms is of crucial importance in the identification of potential therapeutic targets and applications of targeted treatments beyond antimicrobials, such as immunotherapy.

Development and validation of a prognostic nomogram model for ICU patients with alcohol-associated cirrhosis

BACKGROUND

The prognosis of patients with alcohol-associated cirrhosis (ALC) admitted to the intensive care unit (ICU) is poor. We developed and validated a nomogram (NIALC) for ICU patients with ALC.

METHODS

Predictors of mortality were defined by a machine learning method in a cohort of 394 ICU patients with ALC from the Medical Information Mart for Intensive Care database. Then the nomogram (NIALC) was constructed and evaluated using the AUC. The MELD, MELD-sodium, Child-Pugh, and CLIF-SOFA scores were then compared with NIALC. Two datasets of 394 and 501 ICU patients with ALC were utilized for model validation.

RESULTS

In-hospital mortality was 41% and 21% in the training and external validation sets. Predictors included were blood urea nitrogen, total bilirubin, prothrombin time, serum creatinine, lactate, partial thromboplastin time, phosphate, mean arterial pressure, lymphocytes, fibrinogen, and albumin. The AUCs for the NIALC were 0.767 and 0.760 in the two validation cohorts, which were better than those of the MELD, MELD-sodium, Child-Pugh, and CLIF-SOFA.

CONCLUSION

We developed a nomogram for ICU patients with ALC, which demonstrated better discriminative ability than previous prognostic scores. This nomogram could be conveniently used to facilitate the individualized prediction of death in ICU patients with ALC.

Assessment of neutrophil subsets and immune checkpoint inhibitor expressions on T lymphocytes in liver transplantation: A preliminary study beyond the neutrophil-lymphocyte ratio

Background: Advanced stages of cirrhosis are characterized by the occurrence of progressive immune alterations known as CAID (Cirrhosis Associated Immune Dysfunction). In advanced cirrhosis, liver transplantation (LT) remains the only curative treatment. Sepsis, shares many similarities with decompensated cirrhosis in terms of immuno-inflammatory response. In both conditions, the neutrophil-lymphocyte ratio (NLR) is associated with poor outcomes. Based on alterations in sepsis, we hypothesized that we could observe in cirrhotic and LT patients more detailed neutrophil and lymphocyte phenotypes. To this end, along with leukocyte count, we assessed immature neutrophils, LOX-1⁺ MDSC and PD-1 and TIM-3 lymphocyte expressions in cirrhotic patients before transplantation in association with liver disease severity and during the first month after transplantation. Methods: We conducted a prospective monocentric study including cirrhotic patients registered on LT waiting-list. Blood samples were collected at enrolment before LT and for 1 month post-LT. In addition to NLR, we assessed by whole blood flow cytometry the absolute count of immature neutrophils and LOX-1⁺ MDSC as well as the expressions of immune checkpoint receptors PD-1 and TIM-3 on T lymphocytes. Results: We included 15 healthy volunteers (HV) and 28 patients. LT was performed for 13 patients. Pre-LT patients presented with a higher NLR compared to HV and NLR was associated with cirrhosis severity. Increased immature neutrophils and LOX-1⁺ MDSC counts were observed in the most severe patients. These alterations were mainly associated with acute decompensation of cirrhosis. PD-1 and TIM-3 expressions on T lymphocytes were not different between patients and HV. Post-LT immune alterations were dominated by a transitory but tremendous increase of NLR and immature neutrophils during the first days post-LT. Then, immune checkpoint receptors and LOX-1⁺ MDSC tended to be overexpressed by the second week after surgery. Conclusion: The present study showed that NLR, immature neutrophils and LOX-1⁺ MDSC counts along with T lymphocyte count and checkpoint inhibitor expression were altered in cirrhotic patients before and after LT. These data illustrate the potential interest of immune monitoring of cirrhotic patients in the context of LT in order to better define risk of sepsis. For this purpose, larger cohorts of patients are now necessary in order to move forward a more personalised care of LT patients.

COVID-19 Vaccination in Patients with Chronic Liver Disease

Vaccination against SARS-CoV-2 has become a central public health issue, primarily for vulnerable populations such as individuals with Chronic Liver Disease (CLD). Increased COVID-19-related mortality and disease severity has been noted in this subgroup of patients. Severe COVID-19 tends to further deregulate liver function in patients with chronic liver failure or cirrhosis and even reactivate hepatitis in people living with HBV or HCV. In addition, impaired hepatic function leads to several limitations in possible therapeutic interventions. Chronic hepatic dysregulation, along with the underlying cirrhosis-associated immune dysfunction (CAID), leads to a decreased immune response to vaccination that, in turn, may result in reduced efficacy rates and lowered lasting protection. According to current guidelines, timely vaccination and frequent booster shot administration are deemed necessary in this context. Vaccination-related adverse events are mostly mild in nature and similar to those reported in the general population, whereas the incidence of liver injury following vaccination is relatively rare. We aimed to review available evidence and recommendations associated with COVID-19 vaccination in patients with chronic liver disease, and provide insight to current issues and future directions.

High prevalence of infections in non-COVID-19 patients admitted to the Emergency Department with severe lymphopenia

Background

In the Emergency Department (ED), early and accurate recognition of infection is crucial to prompt antibiotic therapy but the initial presentation of patients is variable and poorly characterized. Lymphopenia is commonly associated with bacteraemia and poor outcome in intensive care unit patients. The objective of this retrospective study was to assess the prevalence of community-acquired infection in a cohort of unselected patients admitted to the ED with undifferentiated symptoms and severe lymphopenia.

Methods

This is a retrospective single-center study conducted over a 1 year-period before the COVID-19 pandemic. Consecutive adult patients admitted to the ED with severe lymphopenia (lymphocyte count < 0.5 G/L) were studied. Patients with hematological or oncological diseases, HIV infection, hepato-cellular deficiency, immunosuppression, or patients over 85 years old were excluded. Diagnoses of infection were validated by an independent adjudication committee. The association between various parameters and infection was assessed using a multivariate logistic regression analysis.

Results

Of 953 patients admitted to the ED with severe lymphopenia, 245 were studied (148 men; mean age: 63 ± 19 years). Infection was confirmed in 159 patients (65%) (bacterial: 60%, viral: 30%, other: 10%). Only 61 patients (25%) were referred to the ED for a suspected infection. In the univariate analysis, SIRS criteria (OR: 5.39; 95%CI: 3.04–9.70; p < 0.001) and temperature ≥ 38.3 °C (OR: 10.95; 95%CI: 5.39–22.26; p < 0.001) were strongly associate with infection. In the multivariate analysis, only SIRS criteria (OR: 2.4; 95%CI: 1.48–3.9; p < 0.01) and fever (OR: 3.35; 95%CI: 1.26–8.93; p = 0.016) were independently associated with infection.

Conclusions

The prevalence of underlying infection is high in patients admitted to the ED with lymphopenia, irrespective of the reason for admission. Whether lymphopenia could constitute a valuable marker of underlying infection in this clinical setting remains to be confirmed prospectively in larger cohorts.

Trial registration: No registration required as this is a retrospective study.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07295-5.

Patients with Liver Cirrhosis Show High Immunogenicity upon COVID-19 Vaccination but Develop Premature Deterioration of Antibody Titers

SARS-CoV-2 infection is known to lead to severe morbidity and mortality in patients with liver cirrhosis. For this reason, vaccination of these patients against COVID-19 is widely recommended. However, data regarding immunogenicity in patients with liver cirrhosis is limited and even less is known about the kinetics of antibody response, as well as the optimal timing of booster immunization. We analyzed immunogenicity in 110 patients with liver cirrhosis after receiving two doses of the mRNA-based vaccine BNT162b2 following the standard protocol and compared these results to a control group consisting of 80 healthcare workers. One hundred and six patients with liver cirrhosis (96%) developed antibodies against SARS-CoV-2, compared to 79 (99%) in the control group (p = 0.400). Still, the median SARS-CoV-2 IgG titer was significantly lower in patients with liver cirrhosis compared to the control group (939 vs. 1905 BAU/mL, p = 0.0001). We also analyzed the strength of the antibody response in relation to the time between the second dose and antibody detection. Antibody titers remained relatively stable in the control group while showing a rapid and significant decrease in patients with liver cirrhosis. In conclusion, our data reveals a favorable initial outcome after vaccination with the COVID-19 vaccine BNT162b2 in cirrhotic patients but show a rapid deterioration of the antibody response after time, thereby giving a strong hint towards the importance of early booster immunization for this group of patients.

Cirrhosis-associated immune dysfunction

The term cirrhosis-associated immune dysfunction (CAID) comprises the distinctive spectrum of immune alterations associated with the course of end-stage liver disease. Systemic inflammation and immune deficiency are the key components of CAID. Their severity is highly dynamic and progressive, paralleling cirrhosis stage. CAID involves two different immune phenotypes: the low-grade systemic inflammatory phenotype and the high-grade systemic inflammatory phenotype. The low-grade systemic inflammatory phenotype can be found in patients with compensated disease or clinical decompensation with no organ failure. In this phenotype, there is an exaggerated immune activation but the effector response is not markedly compromised. The high-grade systemic inflammatory phenotype is present in patients with acute-on-chronic liver failure, a clinical situation characterized by decompensation, organ failure and high short-term mortality. Along with high-grade inflammation, this CAID phenotype includes intense immune paralysis that critically increases the risk of infections and worsens prognosis. The intensity of CAID has important consequences on cirrhosis progression and correlates with the severity of liver insufficiency, bacterial translocation and organ failure. Therapies targeting the modulation of the dysfunctional immune response are currently being evaluated in preclinical and clinical studies.

The Significant Morbidity and Mortality Indicators in Patients of Cirrhosis

Background: Cirrhosis progression varies greatly from patient to patient due to a variety of factors, including hepatic reserve, cirrhosis etiology, and the presence of hepatocellular cancer. As a result, determining a prognosis in a patient with cirrhosis remains a difficult task. For nearly three decades, the Child-Pugh score (CPS) has been the gold standard for determining the prognosis of cirrhosis. In the last two decades, many prognostic models and scores like a model for end-stage liver disease (MELD), chronic liver failure-sequential organ failure assessment (CLIF-SOFA) score, peripheral blood lymphocyte to monocyte ratio (LMR) have been presented to predict prognosis in patients with cirrhosis and to choose the best therapy option. The aim of our study is to determine which score is more effective in predicting three-month mortality and whether these scores are equally effective in predicting short-term outcomes.

Materials & methods: In this hospital-based longitudinal study, we analyzed 140 patients with cirrhosis of liver visiting All India Institute of Medical Sciences Bhopal between July 2019 and July 2020. All the 140 patients were followed up for three months to establish short-term outcomes. The blood investigations were done at the time of presentation from all the patients and after three months in the survivors. Various scores were calculated.

Results: The majority of patients (47%) were in Child-Pugh class C. Mean MELD score was 13.54, LMR score was 1.96 and CLIF-SOFA score was 5. The total bilirubin, serum creatinine, international normalized ratio (INR), total leukocyte count, absolute monocyte count, CPS, MELD, CLIF-SOFA were significantly higher in a non-surviving group as compared to the surviving group, whereas the albumin and LMR significantly decreased in the non-surviving group. On performing multivariate regression, LMR and CLIF-SOFA were significant independent risk factors of mortality after adjusting for confounding factors. All the parameters had significant discriminatory power to predict mortality. Discriminatory power of CLIF-SOFA (AUC 0.808; 95% CI: 0.733 to 0.870) was excellent and discriminatory power of CPS (AUC 0.792; 95% CI: 0.716 to 0.856), MELD score (AUC 0.765; 95% CI: 0.685 to 0.832) and LMR (AUC 0.75; 95% CI: 0.669 to 0.819) was acceptable. Among all the parameters, CLIF-SOFA was the best predictor of mortality at a cut-off point of >5 with 80.80% chances of correctly predicting mortality.

Conclusion: The significant morbidity and mortality indicators are high total bilirubin, high creatinine, high INR, high TLC, low platelet count, and low albumin. Among the various scores, CLIF-SOFA is a better predictor of mortality and morbidity. Low LMR and high CLIF-SOFA are significant independent risk factors of mortality at three months.

Variable Normalization of Naïve CD4+ Lymphopenia and Markers of Monocyte and T Cell Activation over the Course of Direct-Acting Anti-Viral Treatment of Chronic Hepatitis C Virus Infection

Chronic hepatitis C virus (HCV) infection is associated with naïve CD4+ T cell lymphopenia and long-standing/persistent elevation of cellular and soluble immune activation parameters, the latter heightened in the setting of HIV co-infection. The underlying mechanisms are not completely understood. However, we recently reported that accelerated peripheral cell death may contribute to naïve CD4+ T cell loss and that mechanistic relationships between monocyte activation, T cell activation, and soluble inflammatory mediators may also contribute. Chronic HCV infection can be cured by direct-acting anti-viral (DAA) therapy, and success is defined as sustained virological response (SVR, undetectable HCV RNA (ribonucleic acid) at 12 weeks after DAA treatment completion). However, there is no general consensus on the short-term and long-term immunological outcomes of DAA therapy. Here, we consolidate previous reports on the partial normalization of naïve CD4+ lymphopenia and T cell immune activation and the apparent irreversibility of monocyte activation following DAA therapy in HCV infected and HCV/HIV co-infected individuals. Further, advanced age and cirrhosis are associated with delayed or abrogation of immune reconstitution after DAA therapy, an indication that non-viral factors also likely contribute to host immune dysregulation in HCV infection.

Natural Killer Cells and Regulatory T Cells Cross Talk in Hepatocellular Carcinoma: Exploring Therapeutic Options for the Next Decade

Despite major advances in immunotherapy, hepatocellular carcinoma (HCC) remains a challenging target. Natural Killer (NK) cells are crucial components of the anti-HCC immune response, which can be manipulated for immunotherapeutic benefit as primary targets, modulators of the tumour microenvironment and in synchronising with tumour antigen specific effector CD8 cells for tumour clearance. Regulatory T cells shape the anti-tumour response from effector T cells via multiple suppressive mechanisms. Future research is needed to address the development of novel NK cell-targeted immunotherapy and on restraining Treg frequency and function in HCC. We have now entered a new era of anti-cancer treatment using checkpoint inhibitor (CPI)-based strategies. Combining GMP-NK cell immunotherapy to enhance the frequency of NK cells with CPI targeting both NK and CD8 T cells to release co-inhibitory receptors and enhance the cells anti-tumour immunity of HCC would be an attractive therapeutic option in the treatment of HCC. These therapeutic approaches should now be complemented by the application of genomic, proteomic and metabolomic approaches to understanding the microenvironment of HCC which, together with deep immune profiling of peripheral blood and HCC tissue before and during treatment, will provide the much-needed personalised medicine approach required to improve clinical outcomes for patients with HCC.

Naïve CD4+ T Cell Lymphopenia and Apoptosis in Chronic Hepatitis C Virus Infection Is Driven by the CD31+ Subset and Is Partially Normalized in Direct-Acting Antiviral Treated Persons

Background

The mechanisms underlying naïve CD4+ lymphopenia during chronic Hepatitis C Virus (HCV) infection are unclear. Whether direct-acting antiviral (DAA) therapy restores peripheral naïve CD4+ T cell numbers and function is unknown.

Methods

We enumerated frequencies and counts of peripheral naïve CD4+, CD4+CD31+ and CD4+CD31- T cells by flow cytometry in a cross sectional analysis comparing chronic HCV infected (n=34), DAA-treated(n=29), and age-range matched controls (n=25), as well as in a longitudinal cohort of HCV DAA treated persons (n=16). The cross-sectional cohort was stratified by cirrhosis state. Cell apoptosis/survival (AnnexinV+7AAD+/BCL-2 labeling) and cell cycle entry (Ki67 expression) of CD31+ and CD31- naïve CD4+ T cells was analyzed directly ex vivo and following 3 and 5 days of in vitro culture with media, interleukin (IL) -7 or CD3/CD28 activator.

Results

In the cross-sectional cohort, naïve CD4+ proportions were lower in chronic HCV infected persons compared to controls and DAA-treated persons, an effect in part attributed to cirrhosis. Age was associated with naïve cell counts and proportions in HCV infected and treated persons as well. Naïve CD4+ cell proportions negatively correlated with plasma levels of soluble CD14 following therapy in DAA-treated persons. Naïve CD4+ cells from HCV infected persons exhibited greater direct ex vivo apoptosis and cell-cycling compared to cells from DAA-treated persons and controls, and this was localized to the CD4+CD31+ subset. On the other hand, no remarkable differences in expression of BCL-2 or IL-7 Receptor (CD127) at baseline or following in vitro media or IL7 containing culture were observed. In the longitudinal cohort, naïve CD4+CD31+/CD31- ratio tended to increase 24 weeks after DAA therapy initiation.

Conclusions

Activation and apoptosis of peripheral naïve CD4+CD31+ T cells appear to contribute to naïve CD4+ lymphopenia in chronic HCV infection, and this defect is partially reversible with HCV DAA therapy. Age and cirrhosis -associated naïve CD4+ lymphopenia is present both before and after HCV DAA therapy. These findings have implications for restoration of host immune function after DAA therapy.

Characterization of Blood Immune Cells in Patients With Decompensated Cirrhosis Including ACLF

Background and Aims

Patients with cirrhosis and acute-on-chronic liver failure (ACLF) have immunosuppression, indicated by an increase in circulating immune-deficient monocytes. The aim of this study was to investigate simultaneously the major blood-immune cell subsets in these patients.

Material and Methods

Blood taken from 67 patients with decompensated cirrhosis (including 35 critically ill with ACLF in the intensive care unit), and 12 healthy subjects, was assigned to either measurements of clinical blood counts and microarray (genomewide) analysis of RNA expression in whole-blood; microarray (genomewide) analysis of RNA expression in blood neutrophils; or assessment of neutrophil antimicrobial functions.

Results

Several features were found in patients with ACLF and not in those without ACLF. Indeed, clinical blood count measurements showed that patients with ACLF were characterized by leukocytosis, neutrophilia, and lymphopenia. Using the CIBERSORT method to deconvolute the whole-blood RNA-expression data, revealed that the hallmark of ACLF was the association of neutrophilia with increased proportions of macrophages M0-like monocytes and decreased proportions of memory lymphocytes (of B-cell, CD4 T-cell lineages), CD8 T cells and natural killer cells. Microarray analysis of neutrophil RNA expression revealed that neutrophils from patients with ACLF had a unique phenotype including induction of glycolysis and granule genes, and downregulation of cell-migration and cell-cycle genes. Moreover, neutrophils from these patients had defective production of the antimicrobial superoxide anion.

Conclusions

Genomic analysis revealed that, among patients with decompensated cirrhosis, those with ACLF were characterized by dysregulation of blood immune cells, including increases in neutrophils (that had a unique phenotype) and macrophages M0-like monocytes, and depletion of several lymphocyte subsets (including memory lymphocytes). All these lymphocyte alterations, along with defective neutrophil superoxide anion production, may contribute to immunosuppression in ACLF, suggesting targets for future therapies.

Dysregulated Adaptive Immunity Is an Early Event in Liver Cirrhosis Preceding Acute-on-Chronic Liver Failure

Introduction

Acute-on-chronic liver failure (ACLF) is characterized by high levels of systemic inflammation and parallel suppression of innate immunity, whereas little is known about adaptive immune immunity in ACLF. We therefore aimed to characterize the development of the adaptive immune system during the progression of liver cirrhosis to ACLF. Patients with compensated/stable decompensated liver cirrhosis, acute decompensation of liver cirrhosis, or ACLF were recruited from a prospective cohort study. Comprehensive immunophenotyping was performed using high dimensional flow cytometry. Replication of Torque teno (TT) virus was quantified as a marker of immunosuppression. High frequencies of detectable TT virus were observed already in patients with compensated/stable decompensated liver cirrhosis compared to healthy controls (>50% vs. 19%), suggesting relatively early occurrence of immunosuppression in cirrhosis. In line, profoundly reduced numbers of distinct innate and adaptive immune cell populations were observed before ACLF development. These changes were accompanied by parallel upregulation of co-stimulatory (e.g. CD40L, OX40, CD69, GITR, TIM-1) and inhibitory immune checkpoints (e.g. PDPN, PROCR, 2B4, TIGIT) on CD4+ and CD8+ T cells, which again preceded the development of ACLF. On a functional basis, the capacity of CD4+ and CD8+ T cells to produce pro-inflammatory cytokines upon stimulation was strongly diminished in patients with acute decompensation of liver cirrhosis and ACLF.

Conclusion

Impaired innate and—in particular—adaptive cellular immunity occurs relatively early in the pathogenesis of liver cirrhosis and precedes ACLF. This may contribute to the development of ACLF by increasing the risk of infections in patients with liver cirrhosis.

The Clinical Impact of Cirrhosis on the Hospital Outcomes of Patients Admitted With Influenza Infection: Propensity Score Matched Analysis of 2011-2017 US Hospital Data

BACKGROUND/OBJECTIVES

Patients with cirrhosis have liver-related immune dysfunction that potentially predisposes the patients to increased influenza infection risk. Our study evaluates this cross-sectional relationship using a national registry of hospital patients.

METHODS

This study included the 2011-2017 National Inpatient Sample database. From this, respiratory influenza cases were isolated and stratified using the presence of cirrhosis into a cirrhosis-present study cohort and cirrhosis-absent controls; propensity score matching method was used to match the controls to the study cohort (cirrhosis-present) using a 1:1 matching ratio. The endpoints included mortality, length of stay, hospitalization costs, and influenza-related complications.

RESULTS

Following the match, there were 2,040 with cirrhosis and matched 2,040 without cirrhosis admitted with respiratory influenza infection. Compared to the controls, cirrhosis patients had higher in-hospital mortality (7.79 vs 3.43% p < 0.001, OR 2.38 95% CI 1.78-3.17), longer length of stay (7.25 vs 6.52 d p < 0.001), higher hospitalization costs ($70,009 vs $65,035 p < 0.001), and were more likely be discharged to a skilled nursing facility and home healthcare (vs routine home discharges). In terms of influenza-related complications, the cirrhosis cohort had higher rates of sepsis (29.8 vs 22% p < 0.001, OR 1.51 95% CI 1.31-1.74). In the multivariate regression analysis, cirrhosis was associated with higher mortality (p < 0.001, aOR 2.31 95% CI 1.59-3.35) and length of stay (p = 0.018, aOR 1.03 95% CI 1.01-1.06). In subgroup analysis of patients with decompensated (n = 597) versus compensated cirrhosis (n = 1443), those with decompensated cirrhosis had higher rates of in-hospital mortality (12.7 vs 5.75% p < 0.001, OR 2.39 95% CI 1.72-3.32), length of stay (8.85 vs 6.59 d p < 0.001), and hospitalization costs ($92,858 vs $60,556 p < 0.001). In the multivariate analysis, decompensated cirrhosis was associated with increased mortality (p < 0.001, aOR 2.86 95% CI 1.90-4.32).

CONCLUSION

This study shows the presence of cirrhosis to result in higher hospital mortality and postinfluenza complications in patients with influenza infection.

Dendritic Cell and T Cell Crosstalk in Liver Fibrogenesis and Hepatocarcinogenesis: Implications for Prevention and Therapy of Liver Cancer

Liver fibrosis is a chronic, highly prevalent disease that may progress to cirrhosis and substantially increases the risk for development of hepatocellular carcinoma (HCC). Fibrotic livers are characterized by an inflammatory microenvironment that is composed of various immunologically active cells, including liver-resident populations (e.g., Kupffer cells, hepatic stellate cells and sinusoidal endothelium) and infiltrating leukocytes (e.g., monocytes, monocyte-derived macrophages, neutrophils and lymphocytes). While inflammatory injury drives both fibrogenesis and carcinogenesis, the tolerogenic microenvironment of the liver conveys immunosuppressive effects that encourage tumor growth. An insufficient crosstalk between dendritic cells (DCs), the professional antigen presenting cells, and T cells, the efficient anti-tumor effector cells, is one of the main mechanisms of HCC tumor tolerance. The meticulous analysis of patient samples and mouse models of fibrosis-HCC provided in-depth insights into molecular mechanisms of immune interactions in liver cancer. The therapeutic modulation of this multifaceted immunological response, e.g., by inhibiting immune checkpoint molecules, in situ vaccination, oncolytic viruses or combinations thereof, is a rapidly evolving field that holds the potential to improve the outcome of patients with HCC. This review aims to highlight the current understanding of DC–T cell interactions in fibrogenesis and hepatocarcinogenesis and to illustrate the potentials and pitfalls of therapeutic clinical translation.

Modeling of the immune response in the pathogenesis of solid tumors and its prognostic significance

BACKGROUND

Tumor initiation and subsequent progression are usually long-term processes, spread over time and conditioned by diverse aspects. Many cancers develop on the basis of chronic inflammation; however, despite dozens of years of research, little is known about the factors triggering neoplastic transformation under these conditions. Molecular characterization of both pathogenetic states, i.e., similarities and differences between chronic inflammation and cancer, is also poorly defined. The secretory activity of tumor cells may change the immunophenotype of immune cells and modify the extracellular microenvironment, which allows the bypass of host defense mechanisms and seems to have diagnostic and prognostic value. The phenomenon of immunosuppression is also present during chronic inflammation, and the development of cancer, due to its duration, predisposes patients to the promotion of chronic inflammation. The aim of our work was to discuss the above issues based on the latest scientific insights. A theoretical mechanism of cancer immunosuppression is also proposed.

CONCLUSIONS

Development of solid tumors may occur both during acute and chronic phases of inflammation. Differences in the regulation of immune responses between precancerous states and the cancers resulting from them emphasize the importance of immunosuppressive factors in oncogenesis. Cancer cells may, through their secretory activity and extracellular transport mechanisms, enhance deterioration of the immune system which, in turn, may have prognostic implications.

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. β-blockers have been reported to decrease BT and improve splenomegaly. This study explores the modulation of β1 and β2 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 β1 and β2 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.

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.

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.

Sepsis in Patients With Cirrhosis Awaiting Liver Transplantation: New Trends and Management

Bacterial infections are more frequent and severe in patients with advanced liver disease and, therefore, in liver transplant candidates. The increased risk of infection in these patients parallels the severity of the immune dysfunction associated with cirrhosis, which is related to systemic inflammation and progressive immunodeficiency. Other factors contribute to this risk, such as genetic polymorphisms, proton pump inhibitor overuse, the numerous invasive procedures and hospitalizations these patients go through, or the immunosuppressive effects of malnutrition or alcohol abuse. Bacterial infections have a great impact on disease progression and significantly increase mortality rates before and after liver transplantation. Mechanisms leading to organ failure in sepsis are associated not only with the hemodynamic derangement but also with an excessive inflammatory response triggered by infection. Furthermore, prophylactic and empirical antibiotic treatment strategies in patients with cirrhosis are being modified according to the growing prevalence of multidrug-resistant bacteria in the past decade. Also, new criteria have been introduced for the diagnosis of sepsis and septic shock. These new definitions have been validated in patients with cirrhosis and show a better accuracy to predict in-hospital mortality than previous criteria based on systemic inflammatory response syndrome. Accurate prophylaxis and early identification and treatment of bacterial infections are key to reducing the burden of sepsis in patients with cirrhosis awaiting liver transplantation.

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-1^highICOS⁺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.

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.

Altered Microbiome in Patients With Cirrhosis and Complications

In patients with cirrhosis, the gut microbiome are affected by multiple gut and systemic alterations. These changes lead to dysbiosis in the microbiota of different parts of the body, resulting in inflammation. The constant immune stimulation resulting in part from dysbiosis is associated with morbidity in patients with cirrhosis. Dysbiosis as a dynamic event worsens with decompensation such as with hepatic encephalopathy, infections or acute-on-chronic liver failure (ACLF). These microbial patterns could be applied as diagnostic and prognostic measures in cirrhosis in the outpatient and inpatient setting. Current therapies for cirrhosis have differing impacts on gut microbial composition and functionality. Dietary modifications and the oral cavity have emerged as newer targetable factors to modulate the microbiome, which could affect inflammation and, potentially improve outcomes. Additionally, fecal microbial transplant is being increasingly studied to provide compositional and functional modulation of the microbiome. Ultimately, a combination of targeted therapies may be needed to provide an optimal gut milieu to improve outcomes in cirrhosis.

Infections in Liver Transplantation

Liver transplantation has become an important treatment modality for patients with end-stage liver disease/cirrhosis, acute liver failure, and hepatocellular carcinoma. Although surgical techniques and immunosuppressive regimens for liver transplantation have improved significantly over the past 20 years, infectious complications continue to contribute to the morbidity and mortality in this patient population. The use of standardized screening protocols for both donors and recipients, coupled with targeted prophylaxis against specific pathogens, has helped to mitigate the risk of infection in liver transplant recipients. Patients with chronic liver disease and cirrhosis have immunological deficits that place them at increased risk for infection while awaiting liver transplantation. The patient undergoing liver transplantation is prone to develop healthcare-acquired infections due to multidrug-resistant organisms that could potentially affect patient outcomes after transplantation. The complex nature of liver transplant surgery that involves multiple vascular and hepatobiliary anastomoses further increases the risk of infection after liver transplantation. During the early post-transplantation period, healthcare-acquired bacterial and fungal infections are the most common types of infection encountered in liver transplant recipients. The period of maximal immunosuppression that occurs at 1–6 months after transplantation can be complicated by opportunistic infections due to both primary infection and reactivation of latent infection. Severe community-acquired infections can complicate the course of liver transplantation beyond 12 months after transplant surgery. This chapter provides an overview of liver transplantation including indications, donor-recipient selection criteria, surgical procedures, and immunosuppressive therapies. A focus on infections in patients with chronic liver disease/cirrhosis and an overview of the specific infectious complications in liver transplant recipients are presented.

Clinical feasibility and efficacy of stereotactic body radiotherapy for hepatocellular carcinoma: A systematic review and meta-analysis of observational studies

BACKGROUND AND PURPOSE

Stereotactic body radiotherapy (SBRT) is an emerging ablative modality for hepatocellular carcinoma (HCC). This study aimed to synthesize available evidence to evaluate the clinical feasibility and efficacy of SBRT for HCC.

MATERIALS AND METHODS

A systematic search was performed of the PubMed, Medline, Embase, and Cochrane Library databases. Primary endpoints were overall survival (OS) and local control (LC), and the secondary endpoint was grade ≥3 complications.

RESULTS

Thirty-two studies involving 1950 HCC patients who underwent SBRT were included. Pooled 1-, 2-, and 3-year OS rates were 72.6% (95% confidence interval [CI]: 65.7-78.6), 57.8% (50.9-64.4), and 48.3% (40.3-56.5), respectively. Pooled 1-, 2-, and 3-year LC rates were 85.7% (95% CI: 80.1-90.0), 83.6% (77.4-88.3), and 83.9% (77.6-88.6), respectively. The median value of median tumor sizes among studies was 3.3 cm (range: 1.6-8.6). Median radiation doses, calculated in dose equivalent with 2 Gy per fraction, ranged from 48 to 114.8 Gy₁₀ (median 83.3 Gy₁₀). Subgroup comparison regarding tumor size showed significant differences for 1- and 2-year OS rates and 1-, 2-, and 3-year LC rates, and that regarding radiation dose showed no difference for OS and a marginal difference for 1-year LC rate. Pooled rates of hepatic and gastrointestinal grade ≥3 complications were 4.7% (95% CI: 3.4-6.5) and 3.9% (2.6-5.6), respectively. Child-Pugh class was significantly correlated with hepatic complication of grade ≥3 in meta-regression analysis (p = 0.013).

CONCLUSION

SBRT for HCC was a feasible option conferring excellent LC persisting up to 3 years. Both OS and LC were affected by tumor size, and radiation dose marginally affected LC. Severe complications rarely occurred, but liver function should be considered to avoid serious hepatic toxicity.

Immunodeficiency caused by cirrhosis

The syndrome of decreased immunity caused by cirrhosis is a combination of different immunological mechanisms and reactions which result from an advanced stage of the liver disease. The synthesis of proteins of the acute phase becomes impaired, there develop different deficiencies of the complement system, and there ensues a decrease of receptors that are meant to recognize antigens. The negative changes become apparent in the field of cell responses, e.g. there are changes in the amounts of generated monocytes and macrophages, and their phagocytic capabilities and chemotaxic reactions are impacted as well. The humoral response results in distorted synthesis of particular antigen categories. The risk of detrimental immunoresponses with the end result of endotoxemia is not rarely coupled with both local and global infections. The combination of the aforesaid immunodeficiencies worsens the healing chances of cirrhosis sufferers and more often than not it increases the mortality of the affected patients.

Analysis of hepatitis B surface antigen (HBsAg) using high-sensitivity HBsAg assays in hepatitis B virus carriers in whom HBsAg seroclearance was confirmed by conventional assays

AIM

We investigated the utility of high-sensitivity hepatitis B surface antigen (HBsAg) assays compared with conventional HBsAg assays.

METHODS

Using serum samples from 114 hepatitis B virus (HBV) carriers in whom HBsAg seroclearance was confirmed by conventional HBsAg assays (cut-off value, 0.05 IU/mL), the amount of HBsAg was re-examined by high-sensitivity HBsAg assays (cut-off value, 0.005 IU/mL). Cases negative for HBsAg in both assays were defined as consistent cases, and cases positive for HBsAg in the high-sensitivity HBsAg assay only were defined as discrepant cases.

RESULTS

There were 55 (48.2%) discrepant cases, and the range of HBsAg titers determined by high-sensitivity HBsAg assays was 0.005-0.056 IU/mL. Multivariate analysis showed that the presence of nucleos(t)ide analog therapy, liver cirrhosis, and negative anti-HBs contributed to the discrepancies between the two assays. Cumulative anti-HBs positivity rates among discrepant cases were 12.7%, 17.2%, 38.8%, and 43.9% at baseline, 1 year, 3 years, and 5 years, respectively, whereas the corresponding rates among consistent cases were 50.8%, 56.0%, 61.7%, and 68.0%, respectively. Hepatitis B virus DNA negativity rates were 56.4% and 81.4% at baseline, 51.3% and 83.3% at 1 year, and 36.8% and 95.7% at 3 years, among discrepant and consistent cases, respectively. Hepatitis B surface antigen reversion was observed only in discrepant cases.

CONCLUSIONS

Re-examination by high-sensitivity HBsAg assays revealed that HBsAg was positive in approximately 50% of cases. Cumulative anti-HBs seroconversion rates and HBV-DNA seroclearance rates were lower in these cases, suggesting a population at risk for HBsAg reversion.

Postoperative aspartate aminotransferase to lymphocyte ratio index change is an independent predictor of survival in patients with small hepatocellular carcinoma

Elevated preoperative aspartate aminotransferase (AST) to lymphocyte ratio index (ALRI) is reported to be a prognostic factor for patients with hepatocellular carcinoma (HCC) after treatment. However, [DELTA] ALRI which represents the change from postoperative ALRI to preoperative ALRI change has received little attention. The present study was designed to evaluate the prognostic value of [DELTA] ALRI in small HCC patients after liver resection.A retrospective cohort study was performed to analyze 241 patients with small HCC who underwent liver resection. Patients were divided into Group A ([DELTA] ALRI < 0, n = 142) and group B ([DELTA] ALRI ≥ 0, n = 99) according to postoperative ALRI change. Clinical data, overall survival (OS), and recurrence-free survival (RFS) were compared between the 2 groups, and a multivariate analysis was used to identify prognostic factors.The 1, 3, and 5-year OS rates were 96.5%, 84.9%, and 70.8%, respectively, for group A, and 94.9%, 75.8%, and 59.7%, respectively for group B (P = .014). The corresponding 1, 3, and 5-year RFS rates were 78.2%, 54.6%, and 52.3%, respectively, for group A, and 62.6%, 40.1%, 24.5%, respectively, for group B (P < .001). The results of univariate and multivariate analysis indicated that [DELTA] ALRI was an independent prognostic factor for both RFS (P < .001, hazard ratio [HR] 2.192, 95% confidence interval 1.527-3.147) and OS (P < .001, HR 2.381, 95% confidence interval 1.503-3.771).A positive [DELTA] ALRI after liver resection predicts decreased OS and RFS in patients with small HCC.

Sepsis in alcohol-related liver disease

Alcohol-related liver disease (ALD) remains the most important cause of death due to alcohol. Infections, particularly bacterial infections, are one of the most frequent and severe complications of advanced ALDs, such as alcoholic cirrhosis and severe alcoholic hepatitis (sAH). The specific mechanisms responsible for this altered host defence are yet to be deciphered. The aim of the present study is to review the current knowledge of infectious complications in ALD and its pathophysiological mechanisms, distinguishing the role of alcohol consumption and the contribution of different forms of ALD. To date, corticosteroids are the only treatment with proven efficacy in sAH, but their impact on the occurrence of infections remains controversial. The combination of an altered host defence and corticosteroid treatment in sAH has been suggested as a cause of opportunistic fungal and viral infections. A high level of suspicion with systematic screening and prompt, adequate treatment are warranted to improve outcomes in these patients. Prophylactic or preemptive strategies in this high-risk population might be a preferable option, because of the high short-term mortality rate despite adequate therapies. However, these strategies should be assessed in well-designed trials before clinical implementation.

Pre-Transplantation Immune Cell Distribution and Early Post-Transplant Fungal Infection Are the Main Risk Factors of Liver Transplantation Recipients in Lower Model of End-Stage Liver Disease

BACKGROUND

The prognosis of patients after liver transplantation (LTx) with high Model of End-Stage Liver Disease (MELD) score (>30) is predicted, but patients with lower MELD scores (<30) have no conclusive studies of pre- and post-transplant risk factors that influence the long-term outcome.

METHODS

This retrospective study reviewed 268 recipients with MELD score <30, from 2008 to 2013 in our institution, for evaluation of pre-transplant risk factors including patients' clinical background data, pre-transplant lymphocyte subpopulation, and early post-transplant infection complication as predictors for long-term survival after LTx.

RESULTS

The post-transplant patients' survival estimates were 90.7%, 85.1%, and 83.6% at 1, 3, and 5 years, respectively. In multivariate analysis, age >55years, presence of ascites, cluster of differentiation (CD)3 < 93.2 (count/μL), CD4/CD8 <2.4, fungal infection, and more than one site of fungal colonization significantly influenced survival (P = .0003, P = .002, P = .04, P = .004, P < .0001, and P > .0001, respectively). We also noticed that these five factors accumulatively influence the long-term survival rate; this means that in the presence of any two risk factors, the 5-year survival can still be 88.4%, whereas in the presence of any three risk factors, the survival rate dropped to only 57.1%.

CONCLUSIONS

Older patients in the presence of pre-transplant low immune cell number and ascites in association with post-transplant fungal infection are the independent risk factors in MELD scores <30 LTx groups for long-term survival. Patients in these groups with any of the three factors had inferior long-term survival results.

Stereotactic body radiotherapy for primary hepatic malignancies - Report of a phase I/II institutional study

BACKGROUND AND PURPOSE

To report outcomes and toxicities of a single-institution phase I/II study of stereotactic body radiotherapy (SBRT) in the treatment of unresectable hepatocellular cancer (HCC) and intrahepatic cholangiocarcinoma (IHC).

MATERIALS AND METHODS

Patients with Child-Pugh score less than 8 were eligible. A total of 32 lesions in 26 patients were treated with SBRT. Kaplan-Meier survival analysis was performed. Toxicities were graded by CTCAEv4 criteria and response was scored by EASL guidelines.

RESULTS

Median prescribed dose was 55Gy (range 40-55Gy) delivered in 5 fractions. Mean tumor diameter was 5.0cm and mean GTV was 107cc. Median follow-up was 8.8months with a median survival of 11.1months, and one-year overall survival was 45%. Overall response rate was 42% and one-year local control was 91%. Nine patients experienced a decline in Child-Pugh class following treatment, and two grade 5 hepatic failure toxicities occurred during study follow-up.

CONCLUSIONS

Primary hepatic malignancies not amenable to surgical resection portend a poor prognosis, despite available treatment options. Though radiation-induced liver disease (RILD) is rare following SBRT, this study demonstrates a risk of hepatic failure despite adherence to protocol constraints.

Thymic hyperplasia after chemotherapy in adults with mature B cell lymphoma and its influence on thymic output and CD4(+) T cells repopulation

To investigate the thymic regenerative potential in adults accepting chemotherapy for lymphoma. The dynamics of thymic activity in 54 adults from baseline to 12 mo post-chemotherapy was analyzed by assessing thymic structural changes with serial computed tomography (CT) scans, and correlating these with measurements of thymic output by concurrent analysis of single-joint (sj) T-cell receptor excision circles (sjTREC) and CD31⁺ recent thymic emigrants (RTE) in peripheral blood. Furthermore, the consequence of thymic renewal on peripheral CD4⁺ T cell recovery after chemotherapy was evaluated. Time-dependent changes of thymic size and thymic output assessed by both sjTREC levels and CD31⁺ RTE counts in peripheral blood were observed during and after chemotherapy. Enlargement of thymus over baseline following chemotherapy regarded as rebound thymic hyperplasia (TH) was identified in 20 patients aged 18−53 y (median 33 y). By general linear models repeated measure analysis, it was found that, patients with TH (n = 20) had a faster recovery of sjTREC levels and CD31⁺ RTE counts after chemotherapy than patients with comparable age, gender, diagnosis, disease stage, thymic volume and output function at baseline but without TH (n = 18) (p = 0.035, 0.047); besides, patients with TH had a faster repopulation of both naïve CD4⁺ T cell and natural regulatory CD4⁺ T cell subsets than those without TH (p = 0.042, 0.038). These data suggested that adult thymus retains the capacity of regeneration after chemotherapy, especially in young adults. The presence of TH could contribute to the renewal of thymopoiesis and the replenishment of peripheral CD4⁺ T cell pool following chemotherapy in adults.

Mechanisms of susceptibility to bacterial infections in cirrhotic patients

Bacterial infections are very common in cirrhotic patients, and the incidence is 4-5 times higher than that in the general population. The mechanisms of susceptibility to bacterial infections in cirrhotic patients include intestinal bacterial overgrowth, bacterial translocation, increased number of potentially pathogenic bacteria accompanied by reduced number of beneficial bacteria; small bowel motility disturbances and delayed gut transit, increased intestinal permeability; genetic predisposition to bacterial infections; immunodeficiency accompanied by persistent activation of the immune cells with production of pro-inflammatory cytokines. In this paper, we will discuss the mechanisms of susceptibility to bacterial infections in cirrhotic patients.

Liver inflammation abrogates immunological tolerance induced by Kupffer cells

The liver is essential for inducing immunological tolerance toward harmless antigens to maintain immune system homeostasis. However, the precise cellular mechanisms of tolerance induction against particle-bound antigens, the role of the local hepatic microenvironment, and implications for therapeutic targets in immune-mediated diseases are currently unclear. In order to elucidate cellular mechanisms of tolerance induction in healthy and injured liver, we developed a novel in vivo system combining the systemic delivery of low-dose peptide antigens coupled to inert particles, immunological readouts, and sophisticated intravital multiphoton microscopy-based imaging of liver in mice. We show that liver resident macrophages, Kupffer cells (KCs), but not hepatic monocyte-derived macrophages or dendritic cells (DCs), are the central cellular scavenger for circulating particle-associated antigens in homeostasis. KC-associated antigen presentation induces CD4 T-cell arrest, expansion of naturally occurring Foxp3(+) CD25(+) interleukin-10-producing antigen-specific regulatory T cells (Tregs) and tolerogenic immunity. Particle-associated tolerance induction in the liver protected mice from kidney inflammation in T-cell-mediated glomerulonephritis, indicating therapeutic potential of targeting KC for immune-mediated extrahepatic disorders. Liver inflammation in two independent experimental models of chronic liver injury and fibrosis abrogated tolerance induction and led to an immunogenic reprogramming of antigen-specific CD4 T cells. In injured liver, infiltrating monocyte-derived macrophages largely augment the hepatic phagocyte compartment, resulting in antigen redistribution between myeloid cell populations and, simultaneously, KCs lose signature markers of their tolerogenic phenotype.

CONCLUSIONS

Hepatic induction of tissue-protective immunological tolerance against particulate antigens is dependent on KCs as well as on a noninflamed liver microenvironment, thereby providing mechanistic explanations for the clinical observation of immune dysfunction and tolerance break in patients with advanced liver diseases.

Immunotherapy in the treatment and prevention of infection in acute-on-chronic liver failure

Chronic liver disease, depicted by gradual destruction and fibrosis of the liver, is a condition with high and probably increasing prevalence worldwide. Its deterioration, acute-on-chronic liver failure (ACLF), is characterized by an in-hospital mortality of up to 65%. Infectious complications are the main precipitants eliciting ACLF and concurrently the main cause of death from ACLF. Patients have a marked susceptibility to bacterial infections, which is thought to arise a consequence of an inadequate immune response to microbial challenge, termed immuneparesis. The pathophysiologic mechanisms remain poorly understood. Treatments aimed at restoring the patients' immune function may prevent onset of ACLF and death from secondary infections. A number of drugs approved for patients with liver disease bear immunomodulatory potential such as albumin, glucocorticoids, N-acetylcysteine. Specific targets have been defined that may lead to development of new immunotherapeutic agents. Here, we summarize the pathophysiology of immuneparesis in ACLF and drug candidates to restore immune function and improve survival in the future.

Absolute lymphocyte count recovery at 1 month after transplantation predicts favorable outcomes of patients with hepatocellular carcinoma

BACKGROUND AND AIMS

Absolute lymphocyte count (ALC) and the recovery of ALC after treatment have been identified as a prognostic biomarker for several malignancies. In this study, we aimed to investigate the prognostic role of peritransplant ALC and ALC recovery after liver transplantation (LT) in hepatocellular carcinoma (HCC) patients.

METHODS

A total of 269 HCC patients undergoing LT were enrolled in our study. Clinicopathological data were retrospectively collected and reviewed. Peritransplant ALC and the change of ALC (2 weeks, 1 month, 3 months post-LT) were carefully monitored. All potential risk factors were analyzed by univariate and multivariate cox regression analysis.

RESULTS

Over a mean follow-up of 35.9 months, 120 recurrences and 89 deaths were recorded. In the multivariate analysis, HCC with ALC no recovery at 1 month after LT (P < 0.001), high pretransplant alpha fetoprotein (P = 0.010), total tumor size > 8 cm (P = 0.003), and beyond Milan criteria (P < 0.001) were four independent risk factors for HCC recurrence. For overall survival (OS) after LT, ALC no recovery at 1 month after LT (P = 0.003), total tumor size > 8 cm (P = 0.011), pretransplant albumin < 2.8 g/dL (P = 0.049), model of end-stage liver disease score > 15 (P = 0.017), and beyond Milan criteria (P = 0.001) were significantly related to poor OS. When subgroup analyses were performed according to the Milan criteria, the results showed that the recovery of ALC at 1 month after LT still indicated longer recurrence-free survival (RFS) (P < 0.001) and OS (P = 0.005) beyond Milan criteria as well as RFS (P < 0.001) within Milan criteria, but not OS (P = 0.157) within Milan criteria.

CONCLUSIONS

ALC recovery at 1 month after LT indicated favorable outcomes of HCC patients.

Cirrhosis-associated immune dysfunction: distinctive features and clinical relevance

The term cirrhosis-associated immune dysfunction refers to the main syndromic abnormalities of immune function, immunodeficiency and systemic inflammation that are present in cirrhosis. The course of advanced cirrhosis, regardless of its aetiology, is complicated by cirrhosis-associated immune dysfunction and this constitutes the pathophysiological hallmark of an increased susceptibility to bacterial infection, distinctive of the disease. Cirrhosis impairs the homeostatic role of the liver in the systemic immune response. Damage to the reticulo-endothelial system compromises the immune surveillance function of the organ and the reduced hepatic synthesis of proteins, involved in innate immunity and pattern recognition, hinders the bactericidal ability of phagocytic cells. Systemic inflammation, in form of activated circulating immune cells and increased serum levels of pro-inflammatory cytokines, is the result of persistent episodic activation of circulating immune cells from damage-associated molecular patterns, released from necrotic liver cells and, as cirrhosis progresses, from pathogen-associated molecular patterns, released from the leaky gut. Cirrhosis-associated immune dysfunction phenotypes switch from predominantly "pro-inflammatory" to predominantly "immunodeficient" in patients with stable ascitic cirrhosis and in patients with severely decompensated cirrhosis and extra-hepatic organ failure (e.g. acute-on-chronic liver failure), respectively. These cirrhosis-associated immune dysfunction phenotypes represent the extremes of a spectrum of reversible dynamic events that take place during the course of cirrhosis. Systemic inflammation can affect the functions of tissue somatic cells and modify the clinical manifestation of cirrhosis. The best characterized example is the contribution of systemic inflammation to the haemodynamic derangement of cirrhosis, which correlates negatively with prognosis.

Influence of hepatitis C virus coinfection on CD4⁺ T cells of HIV-infected patients receiving HAART

OBJECTIVE

The effects of hepatitis C virus (HCV) coinfection on immune homeostasis and immune restoration in treated HIV infection are not well understood.

METHODS

We studied 79 HIV-infected patients who had been receiving HAART for more than 2 years and who had HIV viral load below 50 copies/ml. Four patient groups were studied: HIV/HCV, CD4⁺ cells above 350/μl; HIV/HCV, CD4 cells below 350/μl; HIV/HCV, CD4 cells above 350/μl; HIV/HCV, CD4⁺ cells below 350/μl. Controls comprised 20 healthy volunteers. Naive, central memory, effector memory, and terminal effector CD4⁺ T cells were enumerated. Naive CD4CD31 T cells were counted as recent thymic emigrants (RTEs). Activation state and ex-vivo apoptosis of CD4⁺ T cells, levels of liver enzymes, and aspartate aminotransferase-to-platelet ratio index were evaluated.

RESULTS

CD4⁺ T-cell counts and the numbers of all circulating CD4 T-cell maturation subsets were diminished in HIV infection; CD4⁺ T-cell activation and apoptosis were increased in HIV infection, but none of these indices was affected by HCV coinfection. RTE numbers were diminished in HIV infection, were inversely related to age, and were increased in women and lower in HIV/HCV patients than in singly HIV-infected patients. In coinfected patients, RTE numbers were inversely related to levels of liver enzymes, but not to HCV viral load.

CONCLUSION

Whereas we could find no relationship between HCV infection and most indices of CD4⁺ T-cell homeostasis or activation, CD4⁺ RTEs are diminished in the circulation of HCV coinfected persons and appear to be related to indices of ongoing hepatic damage or inflammation.

Bacterial infections in cirrhosis: a position statement based on the EASL Special Conference 2013

Bacterial infections are very common and represent one of the most important reasons of progression of liver failure, development of liver-related complications, and mortality in patients with cirrhosis. In fact, bacterial infections may be a triggering factor for the occurrence of gastrointestinal bleeding, hypervolemic hyponatremia, hepatic encephalopathy, kidney failure, and development of acute-on-chronic liver failure. Moreover, infections are a very common cause of repeated hospitalizations, impaired health-related quality of life, and increased healthcare costs in cirrhosis. Bacterial infections develop as a consequence of immune dysfunction that occurs progressively during the course of cirrhosis. In a significant proportion of patients, infections are caused by gram-negative bacteria from intestinal origin, yet gram-positive bacteria are a frequent cause of infection, particularly in hospitalized patients. In recent years, infections caused by multidrug-resistant bacteria are becoming an important clinical problem in many countries. The reduction of the negative clinical impact of infections in patients with cirrhosis may be achieved by a combination of prophylactic measures, such as administration of antibiotics, to reduce the occurrence of infections in high-risk groups together with early identification and management of infection once it has developed. Investigation on the mechanisms of altered gut microflora, translocation of bacteria, and immune dysfunction may help develop more effective and safe methods of prevention compared to those that are currently available. Moreover, research on biomarkers of early infection may be useful in early diagnosis and treatment of infections. The current manuscript reports an in-depth review and a position statement on bacterial infections in cirrhosis.

Risk factors and outcome of bacterial infections in cirrhosis

Viable and non-viable pathological bacterial translocation promote a self-perpetuating circle of dysfunctional immune activation and systemic inflammation facilitating infections and organ failure in advanced cirrhosis. Bacterial infections and sepsis are now recognized as a distinct stage in the natural progression of chronic liver disease as they accelerate organ failure and contribute to the high mortality observed in decompensated cirrhosis. The increasing knowledge of structural, immunological and hemodynamic pathophysiology in advanced cirrhosis has not yet translated into significantly improved outcomes of bacterial infections over the last decades. Therefore, early identification of patients at the highest risk for developing infections and infection-related complications is required to tailor the currently available measures of surveillance, prophylaxis and therapy to the patients in need in order to improve the detrimental outcome of bacterial infections in cirrhosis.