Tumour necrosis factor-alpha expression by activated monocytes and altered T-cell homeostasis in ascitic alcoholic cirrhosis: amelioration with norfloxacin

A modified prognostic score for critically ill patients with cirrhosis: An observational study

BACKGROUND AND AIMS

It is controversial whether patients with cirrhosis benefit from the intensive care unit (ICU) management. To identify the patients in whom ICU care may offer recovery, this study aimed to determine specific risk factors and to establish a novel prognostic score for 3-month mortality in critically ill patients with cirrhosis.

METHODS

An observational study was performed from August 2008 to May 2014, encompassing 349 critically ill patients with cirrhosis during their ICU stay (a 70% training and 30% validation set).

RESULTS

The overall 3-month mortality rate was 68.1% in training cohort. Prothrombin time, serum bilirubin, use of vasopressors, hepatic encephalopathy, and systemic inflammatory response syndrome at admission were identified as being strongly correlated with the 3-month prognosis. Based on these five variables, a modified score for critically ill cirrhosis (MSCIC) was developed. An increasing MSCIC was significantly correlated with a reduction in the rate of survival (P < 0.001). Moreover, excellent predictive power was found when the MSCIC was used (area under the receiver operating characteristic curve: 0.856 ± 0.047), which was significantly better than the prognostic efficiency of Acute Physiology and Chronic Health Evaluation II (P < 0.001), Model for End-stage Liver Disease (P = 0.02), Simplified Acute Physiology Score (P = 0.023), and the Child-Turcotte-Pugh score (P = 0.01); the MSCIC score was slightly better than that of Chronic Liver Failure-Sequential Organ Failure Assessment (P = 0.068). The similar result was obtained in validation set.

CONCLUSIONS

The MSCIC is an easily adopted tool with a high prognostic efficacy for patients with advanced cirrhosis; MSCIC may act as a supplement to the clinical judgment of physicians when considering the prognosis.

Bifidobacterium pseudocatenulatum CECT7765 induces an M2 anti-inflammatory transition in macrophages from patients with cirrhosis

BACKGROUND & AIMS

Patients with cirrhosis show recurrent access of bacterial products into the bloodstream inducing a multi-altered immunological status leading to relevant complications. We aimed at evaluating Bifidobacterium pseudocatenulatum CECT7765 effect on the host's macrophage function.

PATIENTS & METHODS

Patients with cirrhosis and ascites were included. Granulocyte-macrophage colony-stimulating factor (GM-CSF) monocyte-derived and ascitic fluid (AF) macrophages were cultured with M-CSF, lipopolysaccharide (LPS) and/or the bifidobacterial strain. Pellets and supernatants were evaluated for gene expression of M1 and M2-related genes and cytokine secretion. Cell surface expression molecules were evaluated by flow cytometry. Kupffer cells from bile duct ligated and CCl4 rats were also evaluated.

RESULTS

Experiments were run on GM-CSF blood-derived and AF macrophages from 10 patients with cirrhosis and 10 healthy donors. Different macrophage morphology was observed by optical microscopy in cells stimulated with bifidobacteria vs. LPS. M2-like expression of CD206, CD163 and CD16 was significantly increased in macrophages after stimulation with the bifidobacterial strain vs. LPS. B. pseudocatenulatum CECT7765 was able to significantly change the cytokine secretion pattern of blood-derived and AF macrophages and Kupffer cells from bile duct ligated and CCl4 cirrhotic rats compared to that induced by LPS. B. pseudocatenulatum CECT7765 was also effective in inducing a phenotype transition and a functional change from an M1- to an M2-related gene expression and cytokine secretion pattern in AF macrophages even after LPS-pretreatment. B. pseudocatenulatum CECT7765 did not reduce AF macrophage bacterial killing capacity.

CONCLUSION

B. pseudocatenulatum CECT7765 induces a morphologic, phenotypic and functional transition towards an anti-inflammatory profile in GM-CSF monocyte-derived and AF macrophages from patients with cirrhosis that may help in controlling sustained inflammation in decompensated cirrhosis.

Alcoholic Cirrhosis Increases Risk for Autoimmune Diseases: A Nationwide Registry-Based Cohort Study

BACKGROUND & AIMS

Alcoholic cirrhosis is associated with hyperactivation and dysregulation of the immune system. In addition to its ability to increase risk for infections, it also may increase the risk for autoimmune diseases. We studied the incidence of autoimmune diseases among patients with alcoholic cirrhosis vs controls in Denmark.

METHODS

We collected data from nationwide health care registries to identify and follow up all citizens of Denmark diagnosed with alcoholic cirrhosis from 1977 through 2010. Each patient was matched with 5 random individuals from the population (controls) of the same sex and age. The incidence rates of various autoimmune diseases were compared between patients with cirrhosis and controls and adjusted for the number of hospitalizations in the previous year (a marker for the frequency of clinical examination).

RESULTS

Of the 24,679 patients diagnosed with alcoholic cirrhosis, 532 developed an autoimmune disease, yielding an overall increased adjusted incidence rate ratio (aIRR) of 1.36 (95% confidence interval [CI], 1.24-1.50). The strongest associations were with Addison's disease (aIRR, 2.47; 95% CI, 1.04-5.85), inflammatory bowel disease (aIRR, 1.56; 95% CI, 1.26-1.92), celiac disease (aIRR, 5.12; 95% CI, 2.58-10.16), pernicious anemia (aIRR, 2.35; 95% CI, 1.50-3.68), and psoriasis (aIRR, 4.06; 95% CI, 3.32-4.97). There was no increase in the incidence rate for rheumatoid arthritis (aIRR, 0.89; 95% CI, 0.69-1.15); the incidence rate for polymyalgia rheumatica decreased in patients with alcoholic cirrhosis compared with controls (aIRR, 0.47; 95% CI, 0.33-0.67).

CONCLUSIONS

Based on a nationwide cohort study of patients in Denmark, alcoholic cirrhosis is a risk factor for several autoimmune diseases.

Mechanisms of decompensation and organ failure in cirrhosis: From peripheral arterial vasodilation to systemic inflammation hypothesis

The peripheral arterial vasodilation hypothesis has been most influential in the field of cirrhosis and its complications. It has given rise to hundreds of pathophysiological studies in experimental and human cirrhosis and is the theoretical basis of life-saving treatments. It is undisputed that splanchnic arterial vasodilation contributes to portal hypertension and is the basis for manifestations such as ascites and hepatorenal syndrome, but the body of research generated by the hypothesis has revealed gaps in the original pathophysiological interpretation of these complications. The expansion of our knowledge on the mechanisms regulating vascular tone, inflammation and the host-microbiota interaction require a broader approach to advanced cirrhosis encompassing the whole spectrum of its manifestations. Indeed, multiorgan dysfunction and failure likely result from a complex interplay where the systemic spread of bacterial products represents the primary event. The consequent activation of the host innate immune response triggers endothelial molecular mechanisms responsible for arterial vasodilation, and also jeopardizes organ integrity with a storm of pro-inflammatory cytokines and reactive oxygen and nitrogen species. Thus, the picture of advanced cirrhosis could be seen as the result of an inflammatory syndrome in contradiction with a simple hemodynamic disturbance.

Clinical and pathophysiological consequences of alterations in the microbiome in cirrhosis

Cirrhosis is a major cause of mortality worldwide. Exponential rises in prevalence have been observed secondary to increases in obesity and alcohol consumption. Multiple lines of evidence implicate gut-derived bacteria and bacterial ligands as a central driver of pathogenesis. Recent developments in culture-independent techniques have facilitated a more accurate description of microbiome composition in cirrhosis and led to the description of measures of dysbiosis shown to be associated with disease. More importantly, metagenomic studies are adding to an understanding of the functional contribution of the microbiota and may prove to be a more clinically relevant biomarker than phylogenetic studies. Much like other dysbiotic states such as inflammatory bowel disease, the microbiota in cirrhosis is characterized by a low microbial and genetic diversity. Therapeutic strategies to diminish this process are currently limited to selective intestinal decontamination with antibiotics. This review summarizes the available data and develops a framework for the use of current and future treatment strategies to diminish the consequences of dysbiosis in cirrhosis. Interventional strategies to bind bacterial products in the gut lumen and blood, and modulate the magnitude of host sensing mechanisms remain an unmet clinical need. A greater understanding of the host-microbiota interaction in cirrhosis is of key importance to inform future interventional strategies to diminish the currently escalating burden of the disease.

Gut dysbiosis in acute-on-chronic liver failure and its predictive value for mortality

BACKGROUND

Bacterial translocation from the gut plays an important role in the pathophysiology of acute-on-chronic liver failure (ACLF). However, gut dysbiosis in ACLF was not widely documented in previous studies.

AIM

This research characterized the fecal microbiota in patients with ACLF and analyzed the temporal stability of gut microbiota during illness.

METHODS

Fecal microbiota of 79 ACLF patients (42 patients were followed in the next 4 weeks after the first visit for longitudinal study) and 50 healthy controls was analyzed by 16S ribosomal DNA pyrosequencing.

RESULTS

There was a marked difference between the ACLF group and the control group. The overall microbial diversity and richness were significantly lower in ACLF than in controls. ACLF patients had lower abundance of Bacteroidaceae, Ruminococcaceae, and Lanchnospiraceae, but higher abundance of Pasteurellaceae, Streptococcaceae, and Enterecoccaceae. The relative abundance of Lachnospiraceae was obviously decreased in ACLF patients with hepatic encephalopathy. The gut microbiota kept relatively stable in a short term after the onset of ACLF. The use of antibiotics only showed moderate impacts on the gut microbiota. The relative abundance of Pasteurellaceae and Model of End Stage Liver Disease score were independent factors predicting mortality rate. Network analysis comparison showed robust correlations between specific bacterial families (Ruminococcaceae and Lachnospiraceae) and inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor alpha, IL-2) in ACLF patients.

CONCLUSIONS

These data suggest gut dysbiosis in ACLF and its predictive value for mortality. The results thus open up the possibility of designing diagnostic biomarkers and targeted probiotics aimed at decreasing mortality in ACLF.

Prognostic value of C-reactive protein levels in patients with cirrhosis

I dentifying cirrhosis with a poor short-term prognosis remains crucial for improving the allocation of liver grafts. The purpose of this study was to assess the prognostic value of a model combining the variation of C-reactive protein (CRP) levels within 15 days, the Model for End-Stage Liver Disease (MELD) score, and the presence of comorbidities in patients with decompensated cirrhosis with a Child-Pugh score > B7 and to test the relevance of this model in patients with compensated cirrhosis. We collected data for cirrhotic patients without hepatocellular carcinoma, extrahepatic malignancy, human immunodeficiency virus infection, organ transplantation, seen between January 2010 and December 2011. Multivariate analyses of predictors of 3-month mortality used Cox models adjusted with the age-adjusted Charlson comorbidity index. The prognostic performance [area under receiver operating characteristic curves (AUROCs)] of the 3-variable model was compared to that of the MELD score. The 241 patients who met the inclusion criteria included 109 patients with a Child-Pugh score > B7 who were hospitalized for decompensation. In these patients with severe cases, the 3-month mortality was independently predicted by the MELD score [hazard ratio (HR), 1.10; 95% confidence interval (CI), 1.05-1.14; P < 0.001] and a CRP level > 32 mg/L at the baseline and on day 15 (HR, 2.21; 95% CI, 1.03-4.76; P = 0.042). This model was better than MELD alone (AUROC, 0.789 versus 0.734; P = 0.043). In the whole population with cirrhosis, the 3-month mortality was also predicted by high MELD scores (HR, 1.11; 95% CI, 1.07-1.16; P < 0.001) and a CRP level > 10 mg/L at the baseline and on day 15 (HR, 2.89; 95% CI, 1.29-6.48; P < 0.001), but the AUROCs of the 3-variable model and the MELD score alone were no longer significantly different (0.89 versus 0.88, not significant). In conclusion, prognostic models incorporating variations in CRP predict 3-month mortality in patients with cirrhosis. Such models are particularly relevant for patients with decompensated cirrhosis but provide a limited increase in prediction in comparison with the MELD score in the whole population with cirrhosis.

Hepatorenal syndrome: outcome of response to therapy and predictors of survival

Aim. Treatment of hepatorenal syndrome (HRS) in patients with liver cirrhosis is still challenging and characterized by a very high mortality. This study aimed to delineate treatment patterns and clinical outcomes of patients with HRS intravenously treated with terlipressin. Methods. In this retrospective single-center cohort study, 119 patients (median [IQR]; 56.50 [50.75–63.00] years of age) with HRS were included. All patients were treated with terlipressin and human albumin intravenously. Those with response to treatment (n = 65) were compared to the patient cohort without improvement (n = 54). Patient characteristics and clinical parameters (Child stage, ascites, hepatic encephalopathy, HRS type I/II, and initial MELD score) were retrieved. Univariate analysis of factors influencing the success of terlipressin therapy and Cox regression analysis of factors influencing survival was carried out. Results. One-month survival was significantly longer in the group of responders (p = 0.048). Cox regression analysis identified age [Hazard ratio, 95% confidence interval (CI); 1.05, 1.01–1.09, resp.], alcohol abuse [HR 3.05, 95% CI 1.11–8.38], duration of treatment [HR 0.92, 95% CI 0.88–0.96], and MELD score [HR 1.08, 95% CI 1.02–1.14] to be independent predictors of survival. Conclusions. Survival of HRS patients after treatment depends on age, etiology of liver disease, and the duration of treatment.

Interleukin-1 receptor antagonist correlates with hepatic venous pressure gradient and predicts occurrence of overall complications and bacterial infections in patients with cirrhosis

AIM

The plasma levels of interleukin (IL)-1α, IL-1β and IL-1 receptor antagonist (IL-1Ra) are increased in cirrhotic patients. We aimed to investigate whether these cytokines correlate with hepatic venous pressure gradient (HVPG), the severity of liver cirrhosis and complications of cirrhosis.

METHODS

Sixty-three cirrhotic patients that underwent hemodynamic studies in Taipei Veterans General hospital were enrolled retrospectively. Plasma levels of IL-1α, IL-1β, IL-1Ra and endotoxin were assessed by enzyme-linked immunosorbent assay. Plasma obtained from 11 healthy subjects served as normal controls.

RESULTS

Plasma levels of IL-1α, IL-1β and IL-1Ra were increased in cirrhotic patients compared with controls. IL-1Ra levels significantly correlated with plasma endotoxin levels, Child-Pugh scores, Model of End-Stage Liver Disease (MELD) scores and HVPG. On multivariate analysis, higher IL-1Ra levels (≥760 pg/mL) predicted the occurrence of portal hypertension-related complications and the development of bacterial infections independently of the MELD scores and portal pressure. Furthermore, higher IL-1Ra levels also predicted the survival in patients without hepatocellular carcinoma.

CONCLUSION

The plasma IL-1Ra level correlates with HVPG. Additionally, it may predict the occurrence of portal hypertension-related complications and bacterial infections in cirrhotic patients and the survival in patients without hepatocellular carcinoma.

Neutrophil-to-lymphocyte ratio predicts mortality in patients listed for liver transplantation

BACKGROUND & AIMS

In the absence of overt infection, the systemic inflammatory response is increasingly recognised as a pathogenetic factor in the circulatory dysfunction of advanced cirrhosis. Our aim was to determine whether the neutrophil-to-lymphocyte ratio, a marker of systemic inflammation, is predictive of mortality in patients with end-stage cirrhosis listed for liver transplantation.

METHODS

A single centre study of 570 patients listed for first elective single-organ liver transplantation January 2007-June 2011.

RESULTS

The median listing neutrophil-to-lymphocyte ratio was 2.9 (IQR 1.9-4.7). Neutrophil-to-lymphocyte ratio demonstrated a positive correlation with listing serum bilirubin (P < 0.001), negative correlation with serum sodium (P < 0.001), and positive correlation with the MELD score (P < 0.001). Neutrophil-to-lymphocyte ratio increased with increasing severity of ascites (P < 0.001). A higher neutrophil count (P < 0.001) and lower lymphocyte count (P = 0.001) were predictors of wait-list death. In a multivariate competing risk Cox model, neutrophil-to-lymphocyte ratio remained independently associated with mortality (HR 1.10; 95% CI 1.05-1.15, P < 0.001). The proportion of patients with a neutrophil-to-lymphocyte ratio <2, 2-4.9, and ≥5 who had died by 3 months of listing was 3%, 13.8% and 37.3% respectively (P < 0.001). After adjusting for MELD, increasing increments of neutrophil-to-lymphocyte ratio were predictive of death by 3 months (P = 0.043).

CONCLUSIONS

The blood neutrophil-to-lymphocyte ratio, a simple and readily available marker of systemic inflammation, is an independent predictor of mortality in patients with liver failure listed for liver transplantation.

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.

Role of circulating lymphocytes in patients with sepsis

Sepsis is a systemic inflammatory response syndrome due to infection. The incidence rate is estimated to be up to 19 million cases worldwide per year and the number of cases is rising. Infection triggers a complex and prolonged host response, in which both the innate and adaptive immune response are involved. The disturbance of immune system cells plays a key role in the induction of abnormal levels of immunoregulatory molecules. Furthermore, the involvement of effector immune system cells also impairs the host response to the infective agents and tissue damage. Recently, postmortem studies of patients who died of sepsis have provided important insights into why septic patients die and showed an extensive depletion of CD4 and CD8 lymphocytes and they found that circulating blood cells showed similar findings. Thus, the knowledge of the characterization of circulating lymphocyte abnormalities is relevant for the understanding of the sepsis pathophysiology. In addition, monitoring the immune response in sepsis, including circulating lymphocyte subsets count, appears to be potential biomarker for predicting the clinical outcome of the patient. This paper analyzes the lymphocyte involvement and dysfunction found in patients with sepsis and new opportunities to prevent sepsis and guide therapeutic intervention have been revealed.

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.

Review article: advances in the management of patients with cirrhosis and portal hypertension-related renal dysfunction

BACKGROUND

In cirrhosis, portal hypertension is associated with a spectrum of renal dysfunction that has significant implications for morbidity and mortality.

AIM

To discuss recent progress in the patho-physiological mechanisms and therapeutic options for portal hypertension-related renal dysfunction.

METHODS

A literature search using Pubmed was performed.

RESULTS

Portal hypertension-related renal dysfunction occurs in the setting of marked neuro-humoral and circulatory derangement. A systemic inflammatory response is a pathogenetic factor in advanced disease. Such physiological changes render the individual vulnerable to further deterioration of renal function. Patients are primed to develop acute kidney injury when exposed to additional 'hits', such as sepsis. Recent progress has been made regarding our understanding of the aetiopathogenesis. However, treatment options once hepatorenal syndrome develops are limited, and prognosis remains poor. Various strategies to prevent acute kidney injury are suggested.

CONCLUSION

Prevention of acute kidney injury in high risk patients with cirrhosis and portal hypertension-related renal dysfunction should be a clinical priority.

Immune dysfunction in cirrhosis

Innate and adaptive immune dysfunction, also referred to as cirrhosis-associated immune dysfunction syndrome, is a major component of cirrhosis, and plays a pivotal role in the pathogenesis of both the acute and chronic worsening of liver function. During the evolution of the disease, acute decompensation events associated with organ failure(s), so-called acute-on chronic liver failure, and chronic decompensation with progression of liver fibrosis and also development of disease specific complications, comprise distinct clinical entities with different immunopathology mechanisms. Enhanced bacterial translocation associated with systemic endotoxemia and increased occurrence of systemic bacterial infections have substantial impacts on both clinical situations. Acute and chronic exposure to bacteria and/or their products, however, can result in variable clinical consequences. The immune status of patients is not constant during the illness; consequently, alterations of the balance between pro- and anti-inflammatory processes result in very different dynamic courses. In this review we give a detailed overview of acquired immune dysfunction and its consequences for cirrhosis. We demonstrate the substantial influence of inherited innate immune dysfunction on acute and chronic inflammatory processes in cirrhosis caused by the pre-existing acquired immune dysfunction with limited compensatory mechanisms. Moreover, we highlight the current facts and future perspectives of how the assessment of immune dysfunction can assist clinicians in everyday practical decision-making when establishing treatment and care strategies for the patients with end-stage liver disease. Early and efficient recognition of inappropriate performance of the immune system is essential for overcoming complications, delaying progression and reducing mortality.

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.

Correction of all-trans retinoic acid deficiency in alcoholic cirrhosis lessens the excessive inflammatory monocyte response: a translational study

BACKGROUND & AIMS

Patients with alcoholic liver disease (ALD) have vitamin A (VA) deficiency and an enhanced immune response associated with disease severity. All-trans retinoic acid (ATRA), a VA-active metabolite, has anti-inflammatory effects and its deficiency could contribute to the exacerbated proinflammatory reaction. The aim of this study was to investigate the effects of ATRA/VA deficiency and supplementation on the monocyte response in ALD.

METHODS

Vitamin A and ATRA plasma levels were quantified in ALD patients and healthy subjects (HS). The in vitro effect of ATRA on lipopolysaccharide (LPS)-induced TNF-α production by human peripheral blood mononuclear cells (PBMC) was assessed by ELISA and RT-PCR. The activation pattern of peritoneal macrophages (PerMΦ) and circulating monocytes isolated from VA-deficient mice and ALD patients, respectively, was evaluated by flow cytometry, quantification of TNF-α and NO2 production.

RESULTS

Alcoholic liver disease patients (n = 85) showed plasmatic VA deficiency that was correlated with scores of severity and with the hepatic venous pressure gradient. ATRA levels correlated significantly with VA levels. In vitro, ATRA pretreatment decreased the overproduction of TNF-α by LPS-stimulated PBMC of ALD patients. In vivo, VA deficiency in mice was associated with increased activation of PerMΦ, while oral ATRA supplementation normalized it.

CONCLUSION

For the first time, we show that VA/ATRA deficiencies in ALD patients are associated with disease severity. Furthermore, our data strongly suggest that the VA deficiency observed in ALD patients might participate in the pathophysiology of the disease by priming immune cells, and that ATRA supplementation could downregulate the deleterious proinflammatory state in cirrhosis and might thus be of therapeutic use.

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

BACKGROUND & AIMS

Depletion of circulating CD4(+) T-helper (Th) lymphocytes, especially naive Th cells, is common in cirrhosis. Little is known about the pathogenetic mechanisms involved in Th-cell depletion in cirrhosis. We investigated the mechanisms involved in circulating Th-cell lymphopenia in cirrhosis.

METHODS

Circulating naive and memory Th cells were analyzed by flow cytometry in 60 patients with cirrhosis and 40 sex- and age-matched healthy controls. Thymopoiesis, apoptosis, cell activation, and proliferation were assessed through CD31, annexin-V, HLA-DR and Ki-67 expression, respectively. Lipopolysaccharide (LPS)-binding protein (LBP) and spleen size were measured as indicators of bacterial translocation and splenic pooling, respectively.

RESULTS

Compared to controls, patients showed reduced numbers of Th cells involving a greater depletion of the naive than memory Th-cell compartment (2.7- vs. 1.5-fold, respectively). Recent thymic emigrants were diminished (p < 0.01), and each patient had a lower number of CD31(+) naive Th cells than the matched-control. Spontaneous and induced apoptosis (Annexin-V(+)) of Th cells was increased in patients. Activated (HLA-DR(+)) and proliferating (Ki-67(+)) memory Th cells were increased in patients (p < 0.01), and they directly correlated with plasma LBP (p < 0.05) and negatively with naive Th cells (p < 0.01), respectively. Naive Th cells were inversely correlated (p < 0.01) with their frequencies of apoptosis and of activated memory Th cells, LBP, and spleen size. On multivariate analysis, defective thymic generation of naive Th cells, increased memory Th-cell activation, and splenomegaly were independently associated with Th-cell depletion.

CONCLUSIONS

Th-cell immunodeficiency in cirrhosis is explained by a universal defect in thymopoiesis exacerbated by splenic pooling and activation-driven cell-death induced by bacterial translocation.

Soluble CD163, a marker of Kupffer cell activation, is related to portal hypertension in patients with liver cirrhosis

BACKGROUND

Activation of Kupffer cells may be involved in the pathogenesis of portal hypertension by release of vasoconstrictive substances and fibrosis due to co-activation of hepatic stellate cells.

AIM

To study soluble plasma (s) CD163, a specific marker of activated macrophages, as a biomarker for portal hypertension in patients with liver cirrhosis.

METHODS

We measured sCD163 concentration and the hepatic venous pressure gradient (HVPG) by liver vein catheterisation in 81 cirrhosis patients (Child-Pugh CP-A: n = 26, CP-B: n = 29, CP-C: n = 26) and 22 healthy subjects. We also measured their cardiac output (CO), cardiac index and systemic vascular resistance (SVR). Liver status was examined by Child-Pugh and MELD-score.

RESULTS

In cirrhosis, sCD163 concentration was nearly three times higher than in controls (4.7 ± 2.5 vs. 1.6 ± 0.5 mg/L, P < 0.001). sCD163 was also higher, as measured in steps by CP-score (P < 0.001). The HVPG rose steeply to an asymptote of 22 mmHg with sCD163 up to about 5 mg/L and not to higher values with higher sCD163. In a multivariate analysis, sCD163 was the only independent predictor of the HVPG but did not predict any of the systemic circulatory findings. sCD163 > 3.95 mg/L (upper normal limit) predicted HVPG ≥ 10 mmHg with a positive predictive value of 0.99.

CONCLUSIONS

Circulating sCD163 originating from activated Kupffer cells is increased in cirrhosis with increasing Child-Pugh score and with increasing HVPG, and it is an independent predictor for HVPG. These findings support a primary role of macrophage activation in portal hypertension, and may indicate a target for biological intervention.

Leaky gut and the liver: A role for bacterial translocation in nonalcoholic steatohepatitis

Gut flora and bacterial translocation (BT) play important roles in the pathogenesis of chronic liver disease, including cirrhosis and its complications. Intestinal bacterial overgrowth and increased bacterial translocation of gut flora from the intestinal lumen predispose patients to bacterial infections, major complications and also play a role in the pathogenesis of chronic liver disorders. Levels of bacterial lipopolysaccharide, a component of gram-negative bacteria, are increased in the portal and/or systemic circulation in several types of chronic liver disease. Impaired gut epithelial integrity due to alterations in tight junction proteins may be the pathological mechanism underlying bacterial translocation. Preclinical and clinical studies over the last decade have suggested a role for BT in the pathogenesis of nonalcoholic steatohepatitis (NASH). Bacterial overgrowth, immune dysfunction, alteration of the luminal factors, and altered intestinal permeability are all involved in the pathogenesis of NASH and its complications. A better understanding of the cell-specific recognition and intracellular signaling events involved in sensing gut-derived microbes will help in the development of means to achieve an optimal balance in the gut-liver axis and ameliorate liver diseases. These may suggest new targets for potential therapeutic interventions for the treatment of NASH. Here, we review some of the mechanisms connecting BT and NASH and potential therapeutic developments.

High-sensitivity C-reactive protein levels predict survival and are related to haemodynamics in alcoholic cirrhosis

OBJECTIVES

Inflammation may be implicated in the haemodynamic deterioration and in the development of complications in patients with cirrhosis. High-sensitivity C-reactive protein (hsCRP) is a marker of low-grade inflammation, and predicts outcomes in patients at risk of ischaemic heart disease. Proinflammatory cytokines reflect immune activation and have been found to be elevated in cirrhosis. We investigated a possible association between markers of inflammation and splanchnic and systemic haemodynamics, complications and survival in patients with cirrhosis.

METHODS

In 45 stable patients with cirrhosis on the basis of alcohol consumption, we measured hsCRP, as well as monocyte chemoattractant protein-1, tumour necrosis factor-α, interleukin-6, interleukin-8 and vascular endothelial growth factor in patients and in 12 healthy controls. Systemic and splanchnic haemodynamics were investigated in patients.

RESULTS

hsCRP levels were significantly higher in patients compared with controls (P<0.05) and the highest in patients belonging to Child-Pugh class C. hsCRP levels correlated with markers of liver dysfunction and with the hepatic venous pressure gradient (r=0.48, P<0.001). hsCRP values above the median level of 5.3 mg/l were associated with a highly increased mortality (P=0.001). Model for End-Stage Liver Disease score (P=0.01) and hsCRP (P<0.05) provided independent prognostic information. Cytokines had no discernible value in predicting survival.

CONCLUSION

hsCRP is elevated in patients with cirrhosis and is associated with portal hypertension and decreased survival. hsCRP is a promising prognostic marker in cirrhosis, which may improve the selection of candidates for liver transplantation.

Acute phase proteins in the diagnosis and prediction of cirrhosis associated bacterial infections

BACKGROUND

Bacterial infections are common cause of morbidity and mortality in patients with cirrhosis. The early diagnosis of these infections is rather difficult.

AIMS

To assess the accuracy of acute phase proteins in the identification of bacterial infections.

METHODS

Concentration of C-reactive protein (CRP), procalcitonin (PCT), lipopolysaccharide-binding protein (LBP), sCD14 and antimicrobial antibodies were measured in serum of 368 well-characterized patients with cirrhosis of whom 139 had documented infection. Clinical data was gathered by reviewing the patients' medical charts.

RESULTS

Serum levels of CRP, PCT and LBP were significantly higher in patients with clinically overt infections. Among the markers, CRP - using a 10 mg/L cut-off value- proved to be the most accurate in identifying patients with infection (AUC: 0.93). The accuracy of CRP, however, decreased in advanced stage of the disease, most probably because of the significantly elevated CRP levels in non-infected patients. Combination of CRP and PCT increased the sensitivity and negative predictive value, compared with CRP on its own, by 10 and 5% respectively. During a 3-month follow-up period in patients without overt infections, Kaplan-Meier and proportional Cox-regression analyses showed that a CRP value of >10 mg/L (P = 0.035) was independently associated with a shorter duration to progress to clinically significant bacterial infections. There was no correlation between acute phase protein levels and antimicrobial seroreactivity.

CONCLUSIONS

C-reactive protein on its own is a sensitive screening test for the presence of bacterial infections in cirrhosis and is also a useful marker to predict the likelihood of clinically significant bacterial infections in patients without overt infections.

Endotoxin and tumor necrosis factor-receptor levels in portal and hepatic vein of patients with alcoholic liver cirrhosis receiving elective transjugular intrahepatic portosystemic shunt

BACKGROUND/AIMS

In cirrhosis portal hypertension can promote bacterial translocation and increase serum endotoxin levels. Vice versa, endotoxin aggravates portal hypertension by induction of systemic and splanchnic vasodilation, and by triggering hepatic inflammatory response via tumor necrosis factor α (TNFα). However, the hepatic elimination of endotoxin in cirrhotic patients with severe portal hypertension, in the absence of acute complications, has not been investigated so far.

METHODS

Twenty patients with alcoholic liver cirrhosis received transjugular intrahepatic portosystemic shunt at an event-free interval for either refractory ascites or recurrent bleeding. During the transjugular intrahepatic portosystemic shunt procedure portal and hepatic venous blood samples were obtained and endotoxin levels were measured by a chromogenic limulus-assay. In 16 of these patients an enzyme-linked immunosorbent assay was used to measure levels of the soluble TNFα-receptors sTNF-R55 and sTNF-R75.

RESULTS

Portal venous endotoxin levels correlated with portal vein velocity (P=0.03) and arterial systolic blood pressure (P=0.007). Portal endotoxin levels correlated with portal venous sTNF-R75-levels (P=0.039; r=0.521) and hepatic venous sTNF-R55-levels (P=0.009; r=0.669). Hepatic venous levels of both sTNF-R55 and sTNF-R75 correlated directly with the model for end-stage liver disease-score, and inversely with cholinesterase. However, we did not find significant differences in endotoxin levels nor in sTNF-R55-levels and sTNF-R75-levels between portal and hepatic venous blood.

CONCLUSION

Endotoxin levels correlated with hemodynamic derangement in cirrhotic severe portal hypertension, and with levels of soluble TNFα-receptors. Soluble TNFα-receptor levels correlated with the severity of liver dysfunction. However, in this study an endotoxin concentration gradient across the liver was absent, suggesting negligible primary hepatic endotoxin elimination in the absence of complications.

Glycogen synthase kinase 3 involvement in the excessive proinflammatory response to LPS in patients with decompensated cirrhosis

BACKGROUND & AIMS

In decompensated cirrhosis, the early innate immune response to the Toll-like receptor 4 (TLR4) agonist, lipopolysaccharides (LPS), is characterized by a hyper-production of pro-inflammatory cytokines and hypo-production of the anti-inflammatory cytokine IL-10. In LPS-stimulated non-cirrhotic immune cells, the constitutively active glycogen synthase kinase (GSK) 3 favors pro- vs. anti-inflammatory cytokines, by acting on gene induction. However, in these cells, TLR4 dampens its own pro-inflammatory response by inducing early (within minutes) AKT-mediated phosphorylation of GSK3β (one of two GSK3 isoforms) on Ser9. Phosphorylation of GSK3β (Ser9) inhibits its activity, decreases pro-inflammatory cytokines, and increases IL-10. Thus, we investigated the role of GSK3 in LPS-induced cytokine production by peripheral blood mononuclear cells (PBMCs) or monocytes from patients with advanced cirrhosis and normal subjects.

METHODS

Cells were pre-incubated with or without GSK3 inhibitor (SB216763 or lithium chloride) for 1h and then stimulated with LPS. Cytokine production was assessed at mRNA and secreted proteins levels, by real-time RT-PCR at 1h and ELISA at 20 h, respectively. GSK3β phosphorylation was assessed using Western blotting.

RESULTS

In cirrhotic and normal PBMCs pretreated with GSK3 inhibitors, LPS-induced production of pro-inflammatory proteins TNF-α and IL-12p40 was significantly decreased while that of IL-10 was increased. LPS-induced, AKT-mediated phosphorylation of GSK3β on Ser9 found in normal monocytes, was abolished in cirrhotic cells.

CONCLUSIONS

GSK3 is involved in the early TLR4-mediated pro-inflammatory response in patients with decompensated cirrhosis. This was associated with a defect in AKT-mediated GSK3β phosphorylation resulting in unrestricted 'pro-inflammatory' activity of the enzyme.

Acute-on-chronic liver failure: current concepts on definition, pathogenesis, clinical manifestations and potential therapeutic interventions

In recent years, acute-on-chronic liver failure has been recognized as a specific clinical form of liver failure associated with cirrhosis. The syndrome refers to an acute deterioration of liver function and subsequently of other end organs over a period of weeks following a precipitating event in a patient with previously well- or reasonably well-compensated cirrhosis. These precipitating events include either an indirect (e.g., variceal hemorrhage, sepsis) or a direct (e.g., drug-induced) hepatotoxic factor. The short-term mortality for this condition is more than 50%. At present, considerable efforts are ongoing to better characterize the syndrome, to gain further insight into its pathophysiology and to optimize therapy. This article aims to highlight the current concepts of these various aspects.

Peritoneal macrophage priming in cirrhosis is related to ERK phosphorylation and IL-6 secretion

BACKGROUND

Bacterial infections are common complications arising in patients with cirrhosis and ascites. Translocation of bacterial DNA is a dynamic process that is associated with an increased inflammatory response and a poor prognosis in this setting. The aim of this study was to study whether peritoneal macrophages remain in a chronic primed status to allow a rapid response to subsequent events of bacterial translocation.

PATIENTS AND METHODS

Peritoneal monocyte-derived macrophages were isolated from 25 patients with cirrhosis and non-infected ascites and compared with donor's blood monocytes. Activation cell-surface markers were screened using flow-cytometry, and the phosphorylation state of ERK 1/2, p38 MAP Kinase, PKB/Akt and transcription factors c-Jun and p65 NFκB were evaluated using Western blot. Synthesis of tumour necrosis factor alpha, interleukin 6 (IL-6) and interleukin-10 (IL-10) at baseline and in response to bacterial stimuli was evaluated using ELISA.

RESULTS

A high expression of CD54, CD86 and HLA-DR at baseline was displayed by peritoneal macrophages. Increased phosphorylated levels of ERK1/2, protein kinase B (PKB) and c-Jun, together with IL-6 production, were observed in peritoneal macrophages at baseline compared with donors' blood monocytes. A positive correlation was established between basal IL-6 levels and extracellular signal-regulated kinase (ERK) phosphorylation in peritoneal macrophages from patients with cirrhosis (r=0·9; P=0·005). Addition of lipopolysaccharide induced higher phosphorylation levels of all studied signalling intermediates than synthetic-oligodeoxydinucleotides, but similar end-stage p65 NFκB.

CONCLUSIONS

A sustained immune response is present in ascitic fluid of cirrhotic patients, even in the temporal absence of bacterial antigens. This would facilitate a fast response, probably controlled by IL-6, against repeated bacterial-DNA translocation or in liver chronic inflammation.

Critical role of the liver in the induction of systemic inflammation in rats with preascitic cirrhosis

Systemic activation of the inflammatory immune system contributes to the progression of cirrhosis with ascites. Immune cells become activated after interacting at the mesenteric lymph nodes (MLNs) with bacteria translocated from the gut, and thereafter reach the bloodstream through recirculation. It is unknown whether systemic activation of the immune system is present in pre-ascitic cirrhosis, in which gut bacterial translocation has not been described. The purpose of this study was to determine whether systemic activation of the immune system initiates in rats with compensated carbon tetrachloride (CCl(4))-induced cirrhosis, and if so to establish the activation site of immune cells. We studied the activation status of immune cells in peripheral blood, MLNs, and hepatic lymph nodes (HLNs). Systemic inflammation was present in rats with cirrhosis, as shown by expansion (P < 0.01) of circulating total and inflammatory monocytes and recently activated CD134(+) T helper (T(h)) cells. The same populations of cells were increased (P < 0.01) in MLNs and HLNs. Bacterial translocation was absent in rats with cirrhosis or control rats, but bacterial DNA fragments were present in the MLNs of 54% of rats with cirrhosis. The liver was the source of activated immune cells present in the blood, as shown by the direct correlation between activated T(h) cells in the blood and HLNs, but not in MLNs, and the normalization by gut decontamination with antibiotics of activated cells in MLNs, but not in the blood or HLNs.

CONCLUSION

In experimental cirrhosis, systemic activation of the immune system occurs before ascites development and is driven by recirculation of cells activated in HLNs. In addition, in compensated cirrhosis, bacterial DNA fragments reach the MLNs, where they elicit a local inflammatory response.

Norfloxacin therapy for hepatopulmonary syndrome: a pilot randomized controlled trial

BACKGROUND & AIMS

The hepatopulmonary syndrome occurs in up to one-third of patients with cirrhosis. Animal models of this disease suggest that endotoxemia might cause nitric oxide-mediated vascular dilatation that can be inhibited by the antibiotic norfloxacin. We sought to test this hypothesis in humans.

METHODS

We conducted a pilot randomized, controlled crossover trial of norfloxacin 400 mg twice daily for 4 weeks with a 4-week washout period to assess the feasibility of a larger trial. The primary clinical end point was change in alveolar-arterial oxygen gradient (AaDO₂).

RESULTS

Recruitment was challenging, and change in AaDO₂ was highly variable. We recruited 9 adults (1 woman; age, 60 ± 9 years; AaDO₂, 50 ± 22 mm Hg). AaDO₂ decreased by 0.8 ± 4.8 and 3.4 ± 12.4 mm Hg while on norfloxacin and placebo, respectively (P = .59).

CONCLUSIONS

Recruitment difficulties and variability of the primary outcome measure suggest the need for a multicenter clinical research network for future therapeutic trials in this disease. There was no major effect of norfloxacin on gas exchange in patients with hepatopulmonary syndrome.

Presence of anti-microbial antibodies in liver cirrhosis--a tell-tale sign of compromised immunity?

BACKGROUND

Bacterial translocation plays important role in the complications of liver cirrhosis. Antibody formation against various microbial antigens is common in Crohn's disease and considered to be caused by sustained exposure to gut microflora constituents. We hypothesized that anti-microbial antibodies are present in patients with liver cirrhosis and may be associated with the development of bacterial infections.

METHODOLOGY/PRINCIPAL FINDINGS

Sera of 676 patients with various chronic liver diseases (autoimmune diseases: 266, viral hepatitis C: 124, and liver cirrhosis of different etiology: 286) and 100 controls were assayed for antibodies to Saccharomyces cerevisiae (ASCA) and to antigens derived from two intestinal bacterial isolates (one gram positive, one gram negative, neither is Escherichia coli). In patients with liver cirrhosis, we also prospectively recorded the development of severe episodes of bacterial infection. ASCA and anti-OMP Plus™ antibodies were present in 38.5% and 62.6% of patients with cirrhosis and in 16% and 20% of controls, respectively (p<0.001). Occurrence of these antibodies was more frequent in cases of advanced cirrhosis (according to Child-Pugh and MELD score; p<0.001) or in the presence of ascites (p<0.001). During the median follow-up of 425 days, 81 patients (28.3%) presented with severe bacterial infections. Anti-microbial antibody titers (p = 0.003), as well as multiple seroreactivity (p = 0.036), was associated with infectious events. In logistic regression analysis, the presence of ascites (OR: 1.62, 95%CI: 1.16-2.25), co-morbidities (OR: 2.22, 95%CI: 1.27-3.86), and ASCA positivity (OR: 1.59, 95%CI: 1.07-2.36) were independent risk factors for severe infections. A shorter time period until the first infection was associated with the presence of ASCA (p = 0.03) and multiple seropositivity (p = 0.037) by Kaplan-Meier analysis, and with Child-Pugh stage (p = 0.018, OR: 1.85) and co-morbidities (p<0.001, OR: 2.02) by Cox-regression analysis.

CONCLUSIONS/SIGNIFICANCE

The present study suggests that systemic reactivity to microbial components reflects compromised mucosal immunity in patients with liver cirrhosis, further supporting the possible role of bacterial translocation in the formation of anti-microbial antibodies.

Human brucellosis is characterized by an intense Th1 profile associated with a defective monocyte function

In animal models, a defective Th1 response appears to be critical in the pathogenesis of brucellosis, but the Th1 response in human brucellosis patients remains partially undefined. Peripheral blood from 24 brucellosis patients was studied before and 45 days after antibiotherapy. Twenty-four sex- and age-matched healthy donors were analyzed in parallel. Significantly increased levels of interleukin 1beta (IL-1beta), IL-2, IL-4, IL-6, IL-12p40, gamma interferon (IFN-gamma), and tumor necrosis factor alpha (TNF-alpha), but not of IL-10, in serum and/or significantly increased percentages of samples with detectable levels of these cytokines, measured by enzyme-linked immunosorbent assays (ELISA), were found for untreated brucellosis patients, but these levels were reduced and/or normalized after treatment. Flow cytometry studies showed that the intracytoplasmic expression of IFN-gamma, IL-2, and TNF-alpha, but not that of IL-4, by phorbol myristate-activated CD4(+) CD3(+) and CD8(+) CD3(+) T lymphocytes was significantly increased in untreated brucellosis patients and was also partially normalized after antibiotherapy. The percentage of phagocytic cells, the mean phagocytic activity per cell, and the phagocytic indices for monocytes at baseline were defective and had only partially reverted at follow-up. T lymphocytes from untreated brucellosis patients are activated in vivo and show Th1 cytokine production polarization, with strikingly high serum IFN-gamma levels. In spite of this Th1 environment, we found deficient effector phagocytic activity in peripheral blood monocytes.

Innate immune dysfunction in acute and chronic liver disease

Liver cirrhosis is a common disease causing great public-health concern because of the frequent complications requiring hospital care. Acute liver failure is also prone to several complications but is rare. One of the main complications for both acute and chronic liver diseases is infection, which regularly causes decompensation of cirrhosis, possibly leading to organ failure and death. This review focuses on innate immune function in cirrhosis, acute-on-chronic liver failure and acute liver failure. The known defects of Kupffer cells, neutrophils and monocytes are discussed, together with the pathophysiological importance of gut permeability, portal hypertension and intrinsic cellular defects, and the role of endotoxin, albumin, lipoproteins and toll-like receptors. Based on these different pathomechanisms, the available information on therapeutic strategies is presented. Antibiotic and probiotic treatment, nutritional support, artificial liver support, and experimental strategies such as inhibition of toll-like receptors and use of albumin and colony-stimulating factors are highlighted.

The systemic inflammatory response syndrome in cirrhotic patients: relationship with their in-hospital outcome

BACKGROUND/AIMS

Some evidence suggests that the systemic inflammatory response syndrome (SIRS) contributes to the poor outcome of cirrhotic patients. We studied 141 cirrhotic patients consecutively admitted to a tertiary referral centre assessing prevalence of SIRS and its relationship with in-hospital outcome.

METHODS

Presence of SIRS was assessed on admission and during hospital stay. Main clinical outcomes were death and development of portal hypertension-related complications.

RESULTS

Thirty-nine patients met SIRS criteria. SIRS was present on admission in 20 of 141 patients (14.1%), whereas it occurred during hospital stay in 19 of 121 (15.7%). SIRS was correlated with bacterial infection at admission (p=0.02), jaundice (p=0.011), high serum creatinine levels (p=0.04), high serum bilirubin levels (p=0.002), high international normalized ratio (p=0.046), high model of end-stage liver disease (MELD) score (p=0.001), and high SOFA score (p=0.003). During a follow-up of 14+/-8 days, 16 patients died (11%), 7 developed portal hypertension-related bleeding (5%), 16 hepatic encephalopathy (11%), and 5 hepatorenal syndrome type-1 (3.5%). SIRS was correlated both to death (p<0.001) and to portal hypertension-related complications (p<0.001). On multivariate analysis, SIRS and MELD were independently associated with death.

CONCLUSIONS

SIRS frequently occurs in patients with advanced cirrhosis and is associated with a poor outcome.

Chronic antigenic stimuli as a possible explanation for the immunodepression caused by liver cirrhosis

The objectives of this work were the analysis of the functional characteristics of circulating monocytes and T lymphocytes in patients with liver cirrhosis, and evaluation of the relationship with an increased exposure to antigens due to bacterial translocation. Forty patients with liver cirrhosis (20 with compensated cirrhosis and 20 with ascitic decompensation) and 20 healthy control subjects were studied. Bacterial translocation was evaluated by serum levels of lipopolysaccharide binding protein (LBP). Macrophage activation was studied by CD40 antigen expression. T lymphocytes were analysed for activation (CD25(+), CD122(+)), effector function (CD8(+)CD45RO(+)CD57(+)), apoptosis (CD95(+)) and regulatory abilities, either by analysis of the membrane expression of co-stimulatory molecules CD80, CD86 and CD28, or by quantification of regulatory T cells CD4(+)CD25(high)forkhead box P3 (FoxP3). The percentage of activated monocytes and T lymphocytes in patients was increased significantly. The proportions of effector senescent cells and of those near to apoptosis were also significantly higher. With respect to these proportions, there were no significant differences between patients in function of the presence or absence of decompensation or in function of the increased or normal values of LBP. Conversely, those patients with elevated levels of LBP presented a significantly higher frequency of regulatory T cells than those with normal levels. In conclusion, patients with liver cirrhosis showed an intensive activation state with a higher percentage of cells committed to activation-induced death, even in non-advanced stages. It is possible that bacterial permeability and endotoxaemia contribute to the expansion of those lymphocyte populations implicated in the prevention of a more severe antigen-induced immunopathology.

Protein array technology to investigate cytokine production by monocytes from patients with advanced alcoholic cirrhosis: An ex vivo pilot study

AIM

In patients with advanced cirrhosis, little is known about the ability of peripheral blood monocytes to spontaneously produce signaling proteins such as cytokines. The aim of this ex vivo study was to evaluate cytokine production under baseline conditions and after stimulation by lipopolysaccharide (LPS), a toll-like receptor (TLR) agonist.

METHODS

Peripheral blood monocytes were isolated from patients with advanced alcoholic cirrhosis (without ongoing bacterial infections) and normal subjects. Cells were left unstimulated or were stimulated with LPS. The abundance of 24 cytokines was measured using a filter-based, arrayed sandwich enzyme-linked immunosorbent assay (ELISA) in the supernatant of cultured monocytes.

RESULTS

Cirrhotic monocytes spontaneously produced six proteins (TNF-alpha, IL-6, IL-8, MCP-1, RANTES and Gro), whereas normal monocytes produced only small amounts of IL-8 and RANTES. Analyses with the online gene set analysis toolkit WebGestalt (http://bioinfo.vanderbilt.edu/webgestalt) found enrichment for the six proteins in the human gene ontology subcategory (http://www.geneontology.org), Kyoto Encyclopedia of Genes and Genome pathways (http://www.genome.ad.jp/kegg/) and BioCarta pathways (http://www.biocarta.com/genes/index.asp) consistent with a proinflammatory phenotype of cirrhotic monocytes resulting from activated TLR signaling. Interestingly, LPS-elicited TLR engagement further increased the production of the six proteins and did not induce the secretion of any others, in particular the anti-inflammatory cytokine IL-10. LPS-stimulated normal monocytes produced TNF-alpha, IL-6, IL-8, MCP-1, RANTES, Gro and IL-10.

CONCLUSION

In patients with advanced cirrhosis, peripheral blood monocytes spontaneously produce proinflammatory cytokines, presumably in response to unrestricted TLR signaling.

Low serum concentration of apolipoprotein A-I is an indicator of poor prognosis in cirrhotic patients with severe sepsis

BACKGROUND/AIMS

Severe sepsis is frequently associated with hypocholesterolemia which is also a common finding in cirrhotic patients. Lipoprotein is capable of binding endotoxin to which cirrhotic patients exhibit an excessive pro-inflammatory response.

METHODS

We evaluated the relationship between lipid levels, inflammatory cytokines and clinical outcomes in 103 cirrhotic patients with severe sepsis.

RESULTS

The non-survivors had significantly lower concentrations of total cholesterol, high-density lipoprotein (HDL), and apolipoprotein A-I (APO A-I). HDL and APO A-I levels were inversely correlated with interleukin-6, tumor necrosis factor-alpha, and various disease severity scores. Serum creatinine, mean arterial pressure and low level of APO A-I (<47.5mg/dl) were independent factors to predict 90-day mortality. The cumulative survival rates at 90 days were 63.8% and 8.9% for the high APO A-I and low APO A-I groups (p<0.0001). Low APO A-I was also associated with lower mean arterial pressure, higher rate of vasopressor dependency, and greater plasma renin activity.

CONCLUSIONS

Serum levels of HDL and APO A-I are inversely correlated with liver reserve and disease severity in cirrhotic patients with severe sepsis. Low level of APO A-I is associated with a marked impairment of effective arterial volume, multiple organ dysfunction and a poor prognosis.

Gastrointestinal tract in liver disease: which organ is sick?

PURPOSE OF REVIEW

This article gives an overview of the several morphological and functional alterations in the gastrointestinal tract that occur in liver disease and their systemic impact.

RECENT FINDINGS

Recent endoscopic studies have revealed similar mucosal alterations in the upper gastrointestinal as well as the colon that include inflammatory-like changes and vascular lesions. Gut-barrier integrity is consequently impaired. There is an evidence that bacterial translocation with subsequent endotoxaemia provokes an inflammatory response that might trigger the cachexia syndrome in liver disease. Novel therapeutic approaches that address gut-barrier function such as supplementation with insulin-like growth factor or synbiotics have shown promising results.

SUMMARY

There are various alterations of the gastrointestinal tract in liver disease and portal hypertension, which might be less clinically overt than the cardinal potentially life-threatening features, ascites and oesophageal varices. However, these alterations, for example gut-barrier dysfunction and alterations of gut flora (microbiota) have immense impact on the portal enteropathy, as they both contribute to the systemic inflammation in liver cirrhosis, which is considered a risk factor for infections as well as the development of cachexia.

High-density lipoprotein administration attenuates liver proinflammatory response, restores liver endothelial nitric oxide synthase activity, and lowers portal pressure in cirrhotic rats

In patients with cirrhosis, endotoxic shock is a major complication of portal hypertension, which is related partly to intrahepatic endothelial nitric oxide synthase (eNOS) down-regulation. High-density lipoproteins (HDLs), whose plasma levels are reduced in cirrhosis, have an anti-inflammatory effect by neutralizing circulating lipopolysaccharide (LPS), and they increase eNOS activity in endothelial cells. Therefore, the aim of this study was to assess the effects of reconstituted high-density lipoprotein (rHDL) administration on the LPS-induced proinflammatory response, intrahepatic eNOS regulation, and portal hypertension in cirrhotic rats. Cirrhotic and control rats were pretreated with rHDL or saline and challenged with LPS or saline. The neutralization of LPS in HDL was assessed by the measurement of HDL-bound fluorescent LPS levels. Plasma tumor necrosis factor alpha (TNFalpha) and lipopolysaccharide binding protein (LBP) levels were measured. The expression of hepatic TNFalpha, LBP, inducible nitric oxide synthase (iNOS), and caveolin-1 (a major eNOS inhibitor) and the activity of protein kinase B (Akt; a major eNOS activator) and eNOS were determined. The portal pressure was measured. The plasma HDL levels were significantly lower in cirrhotic rats than in control rats. In cirrhotic rats, the plasma levels of HDL-bound fluorescent LPS were 50% lower than those in controls, and they were restored after rHDL administration. The plasma TNFalpha levels were significantly higher in LPS-challenged cirrhotic rats than in controls and significantly decreased after rHDL administration. rHDL administration decreased hepatic TNFalpha, LBP, iNOS, and caveolin-1 expression, restored hepatic eNOS and Akt activity, and significantly lowered the portal pressure and intrahepatic vascular resistance.

CONCLUSION

In cirrhotic rats, rHDL administration decreases the hepatic proinflammatory signals induced by LPS, restores the hepatic eNOS activity, and lowers the portal pressure. This suggests that the decrease in circulating HDL in cirrhosis plays a role in the excessive proinflammatory response and intrahepatic eNOS down-regulation.

Model for end-stage liver disease score and systemic inflammatory response are major prognostic factors in patients with cirrhosis and acute functional renal failure

Although it is often functional at presentation, acute renal failure has a poor prognosis in patients with cirrhosis. The role of inflammation, a key event in the outcome of cirrhosis, has never been studied in this setting. We aimed to investigate the predictive factors of mortality in patients with cirrhosis and acute functional renal failure, specifically in relation to inflammatory events. One hundred consecutive patients with cirrhosis from 5 French hospitals were prospectively included at the day of onset of acute renal failure. Medical history, treatments, and procedures during the month before inclusion were recorded. Physical examination, blood and urinary chemistries, and renal ultrasound examination were performed. The presence of systemic inflammatory response syndrome (SIRS), infection, and sepsis was assessed. The primary outcome was in-hospital mortality. The mechanism of renal failure was functional in 83 patients. Causes of renal failure were hypovolemia (34%), hepatorenal syndrome without ongoing infection (17%), hepatorenal syndrome with ongoing infection (16%), nephrotoxicity (2%), and multifactorial (31%). SIRS was observed in 41% of patients, 56% of them with infection. In-hospital mortality was 68% in patients with SIRS and 33% in patients without (P = 0.001). In multivariate analysis, only model for end-stage liver disease score and presence of SIRS, but not infection, remained associated with a poor outcome.

CONCLUSION

The presence of SIRS, with or without infection, is a major independent prognostic factor in patients with cirrhosis and acute functional renal failure. This suggests that preventing and treating SIRS could decrease mortality in patients with cirrhosis and acute renal failure.

[Physiopathology of bacterial translocation and spontaneous bacterial peritonitis in cirrhosis]

The key pathogenic mechanism initiating spontaneous bacterial peritonitis (SBP) is bacterial translocation (BT), a process through which enteric bacteria cross the intestinal barrier and infect the mesenteric lymph nodes, thus entering the blood circulation and ascitic fluid. The high rate of bacterial translocation in cirrhosis is due to injury to the three pilars composing the intestinal mucosal barrier (the balance of intraluminal bacterial flora, the integrity of the intestinal epithelial barrier, and the local immune system). Blood dissemination and microbial growth in ascitic fluid resulting from SBP are a consequence of damage to the immune system in cirrhosis. Hyperproduction of proinflammatory cytokines and other vasoactive substances contributes to the arterial vasodilation and renal failure that frequently complicate the course of SBP. Even in the absence of SBP, translocation of bacteria and bacterial products from the intestinal lumen contribute to systemic inactivation of immune cells in cirrhosis.

Infection et rupture de varice œsophagienne au cours de la cirrhose

Endotoxemia and bacterial infection are frequent in patients with cirrhosis. They alter systemic and splanchnic hemodynamics, worsen coagulation disorders, impair liver function and thus may induce variceal bleeding. In variceal bleeding, bacterial infection favours failure to control bleeding, early rebleeding, and death. In patients with cirrhosis and variceal bleeding, antibiotic-prophylaxis decreases bacterial infection and the incidence of early rebleeding, and, more important, significantly decreases the death rate in these patients.

Expression of β2-integrin on leukocytes in liver cirrhosis

AIM: To analyze β2-integrin expression on blood leukocytes in liver cirrhosis.

METHODS: In 40 patients with liver cirrhosis and 20 healthy individuals, the evaluation of expression of CD11a (LFA-1α), CD11b (Mac-1α), CD11c (αX) and CD49d (VLA-4α) on peripheral blood leukocytes was performed using flow cytometry. The analysis was carried out in groups of patients divided into B and C according to Child-Pugh’s classification.

RESULTS: An increased CD11a, CD11b, CD11c and CD49d integrin expression was observed on peripheral blood leukocytes in liver cirrhosis. The integrin levels were elevated as the advancement of liver failure progressed. The highest expression of integrins occurred predominantly on monocytes. A slight expression of VLA-4 was found on lymphocytes and granulocytes and it increased together with liver failure. A positive correlation was noted between median intensity of fluorescence (MIF) expression on polymorphonuclear cells of CD11a and CD11c and CD49d (r = 0.42, P < 0.01; r = 053, P < 0.01, respectively) in liver cirrhosis stage C. However, no correlation was observed between integrin expression on leukocytes. The concentrations of sICAM-1, sVCAM-1, and TNFα, were significantly elevated in liver cirrhosis.

CONCLUSION: β2-integrin expression on leukocytes increases in liver cirrhosis decompensated as the stage of liver failure increases, which is a result of permanent activation of leukocytes circulating through the inflamed liver environment. β2-integrin expression on circulating leukocytes can intensify liver cirrhosis.

Role of intestinal function in cachexia

PURPOSE OF REVIEW

Cachexia is a prominent feature in many chronic diseases, but its pathogenesis is still not fully understood. This article reviews recent research into the role of the gut barrier in the pathogenesis of inflammation and cachexia with special emphasis on two potentially catabolic diseases: liver cirrhosis and chronic heart failure.

RECENT FINDINGS

There is increasing evidence that catabolic diseases such as liver cirrhosis and chronic heart failure are associated with increased gut permeability, endotoxemia and enhanced expression of proinflammatory cytokines. In liver cirrhosis normalization of portal hypertension by insertion of a transjugular intrahepatic portosystemic stent shunt obviously causes improvement not only of gut barrier function, but also of nutritional status.

SUMMARY

Although its pathogenesis is not yet completely understood, proinflammatory cytokines have been implicated in the onset and progression of cachexia. Recent data support the hypothesis that impaired gut barrier function and increased permeability further translocation of endotoxins. Increased endotoxemia might be a potent trigger of systemic inflammatory response which is involved in the pathogenesis of the cachexia syndrome. Thus, it is tempting to speculate that therapeutic strategies for the improvement of gut barrier function will concomitantly improve nutritional status.

Upregulation of TNF-alpha production signaling pathways in monocytes from patients with advanced cirrhosis: possible role of Akt and IRAK-M

BACKGROUND/AIMS

In cirrhosis, tumor necrosis factor (TNF)-alpha overproduction is involved in both the systemic complications and progression of liver injury. Since monocytes from patients with advanced cirrhosis have an increase in lipopolysaccharide (LPS)-induced TNF-alpha production, we hypothesized that an upregulation of TNF-alpha production pathways and/or alteration of constitutive and inducible suppressor of TNF-alpha hyperproduction (protein kinase B (Akt) and interleukin-1 receptor-associated kinase (IRAK)-M, respectively) should be found in monocytes of these patients. Thus, we investigated ex vivo the signaling pathways of TNF-alpha production before and after LPS incubation in monocytes from noninfected Child-Pugh C patients with advanced cirrhosis and healthy subjects.

METHODS

TNF-alpha production, expressions of intracellular TNF-alpha, toll-like receptor-4 (TLR4), IkappaB-alpha, IRAK-1, IRAK-M, mitogen-activated protein (MAP) kinases and Akt activity were measured in monocytes.

RESULTS

Cirrhotic monocytes without LPS have less TLR4 expression, less IkappaB-alpha protein levels, more TNF-alpha expression, higher MAP kinase activities and decreased Akt activity than control monocytes. In cirrhotic monocytes, LPS-induced TNF-alpha hyperproduction and signaling upregulation were associated with a lack of IRAK-M induction.

CONCLUSIONS

Upregulated signaling pathways of the TNF-alpha production, decreased Akt activity and a lack of IRAK-M induction may be involved in the process of cirrhotic monocyte sensitization to produce TNF-alpha.

Treatment With AM3 Restores Defective T-Cell Function in COPD Patients

BACKGROUND

Lymphocyte alterations have been associated with an increased prevalence of acute respiratory infections in COPD patients. AM3 is an oral immunomodulator that normalizes the defective functions of peripheral blood natural killer and phagocytic cells in COPD patients and improves their health-related quality of life.

OBJECTIVES

To characterize putative systemic abnormalities of the T-cell compartment in COPD patients, and to investigate whether AM3 can restore such abnormalities.

DESIGN

The study was a randomized, prospective, double-blind, placebo-controlled trial in a cohort of COPD patients. The results were also compared to those of nonsmoker and ex-smoker healthy control subjects.

SETTING

Outpatient departments of four hospitals.

PATIENTS

Seventy COPD patients were randomized to receive either AM3 or a placebo orally for 90 consecutive days. Populations of 36 healthy nonsmokers and 36 healthy ex-smokers were used as control subjects.

MEASUREMENTS

Peripheral blood mononuclear cell (PBMC) proliferation and production of interleukin (IL)-2, IL-4, IL-12p40, tumor necrosis factor-alpha, and interferon (IFN)-gamma proteins in response to the T-cell polyclonal mitogens were assessed at baseline and at the end of treatment.

RESULTS

The proliferative response was significantly decreased in COPD patients. Decreased production of IFN-gamma was the only defect in the profiles of the cytokine measures, and was selectively observed in COPD patients, but not in nonsmoker and ex-smoker healthy control subjects. Treatment with AM3 significantly restored the PBMC proliferative response to polyclonal mitogens and significantly promoted stimulated IFN-gamma production in these patients. The normalization of these proliferative responses was not related to significant variations in the numbers of peripheral blood monocytes, CD3+, CD4+, CD8+ cells or of any major naïve/memory/activated T-cell subset. The increased IFN-gamma production in the AM3 study arm was associated with an increase in the mean of number of IFN-gamma molecules produced per CD8+ T cells.

CONCLUSIONS

PBMCs of COPD patients showed clear functional T-lymphocyte abnormalities that are rescued by AM3 treatment.