Attenuation of toll-like receptor 2-mediated innate immune response in patients with alcoholic chronic liver disease

Molecular and Cellular Mediators of the Gut-Liver Axis in the Progression of Liver Diseases

The gut-liver axis covers the bidirectional communication between the gut and the liver, and thus includes signals from liver-to-gut (e.g., bile acids, immunoglobulins) and from gut-to-liver (e.g., nutrients, microbiota-derived products, and recirculating bile acids). In a healthy individual, liver homeostasis is tightly controlled by the mostly tolerogenic liver resident macrophages, the Kupffer cells, capturing the gut-derived antigens from the blood circulation. However, disturbances of the gut-liver axis have been associated to the progression of varying chronic liver diseases, such as non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, and primary sclerosing cholangitis. Notably, changes of the gut microbiome, or intestinal dysbiosis, combined with increased intestinal permeability, leads to the translocation of gut-derived bacteria or their metabolites into the portal vein. In the context of concomitant or subsequent liver inflammation, the liver is then infiltrated by responsive immune cells (e.g., monocytes, neutrophils, lymphoid, or dendritic cells), and microbiota-derived products may provoke or exacerbate innate immune responses, hence perpetuating liver inflammation and fibrosis, and potentiating the risks of developing cirrhosis. Similarly, food derived antigens, bile acids, danger-, and pathogen-associated molecular patterns are able to reshape the liver immune microenvironment. Immune cell intracellular signaling components, such as inflammasome activation, toll-like receptor or nucleotide-binding oligomerization domain-like receptors signaling, are potent targets of interest for the modulation of the immune response. This review describes the current understanding of the cellular landscape and molecular pathways involved in the gut-liver axis and implicated in chronic liver disease progression. We also provide an overview of innovative therapeutic approaches and current clinical trials aiming at targeting the gut-liver axis for the treatment of patients with chronic liver and/or intestinal diseases.

Immune Dysfunction in Cirrhosis

Cirrhosis due to any etiology disrupts the homeostatic role of liver in the body. Cirrhosis-associated immune dysfunction leads to alterations in both innate and acquired immunity, due to defects in the local immunity of liver as well as in systemic immunity. Cirrhosis-associated immune dysfunction is a dynamic phenomenon, comprised of both increased systemic inflammation and immunodeficiency, and is responsible for 30% mortality. It also plays an important role in acute as well as chronic decompensation. Immune paralysis can accompany it, which is characterized by increase in anti-inflammatory cytokines and suppression of proinflammatory cytokines. There is also presence of increased gut permeability, reduced gut motility and altered gut flora, all of which leads to increased bacterial translocation. This increased bacterial translocation and consequent endotoxemia leads to increased blood stream bacterial infections that cause systemic inflammatory response syndrome, sepsis, multiorgan failure and death. The gut microbiota of cirrhotic patients has more pathogenic microbes than that of non-cirrhotic individuals, and this disturbs the homeostasis and favors gut translocation. Prompt diagnosis and treatment of such infections are necessary for better survival. We have reviewed the various mechanisms of immune dysfunction and its consequences in cirrhosis. Recognizing the exact pathophysiology of immune dysfunction will help treating clinicians in avoiding its complications in their patients and can lead to newer therapeutic interventions and reducing the morbidity and mortality rates.

Peptide hormones and lipopeptides: from self-assembly to therapeutic applications

This review describes the properties and activities of lipopeptides and peptide hormones and how the lipidation of peptide hormones could potentially produce therapeutic agents combating some of the most prevalent diseases and conditions. The self‐assembly of these types of molecules is outlined, and how this can impact on bioactivity. Peptide hormones specific to the uptake of food and produced in the gastrointestinal tract are discussed in detail. The advantages of lipidated peptide hormones over natural peptide hormones are summarised, in terms of stability and renal clearance, with potential application as therapeutic agents. © 2017 The Authors Journal of Peptide Science published by European Peptide Society and John Wiley & Sons Ltd.

Association between circulating inflammatory molecules and alcoholic liver disease in men

The association between alcoholic liver disease (ALD) and the inflammatory response remains controversial. The aim of this study was to explore this association between ALD and inflammation. We enrolled 214 male participants, who were divided into three age-matched groups: ALD (n = 135), chronic alcohol ingestion without ALD (non-ALD; n = 42), and control (n = 37). The BMI was significantly higher in the ALD group than in the non-ALD and control groups (all P = 0.000). Further, the constituent ratio of the liver inflammatory level was significantly higher in the ALD group than in the non-ALD and control groups (P = 0.002 and P = 0.000, respectively). In addition, the median serum ALT, AST, and GGT levels were significantly higher in the ALD group than in the control group (P = 0.023, P = 0.008, and P = 0.000, respectively); these levels were also significantly higher in the ALD group than in the non-ALD group (P = 0.013, P = 0.010, and P = 0.000, respectively). The median serum CRP level was significantly higher in the ALD group than in the non-ALD and control groups (P = 0.006 and P = 0.000, respectively). Further, the median serum TNF-α level was significantly lower in the ALD group than in the non-ALD and control groups (P = 0.004 and P = 0.000, respectively). The median serum sOX40L and HSP70 levels were significantly lower in the ALD group than in the control group (P = 0.008 and P = 0.018, respectively). In addition, the ALT, AST, and GGT levels were positively correlated with the CRP level (r = 0.211, P = 0.002; r = 0.220, P = 0.001 and r = 0.295, P = 0.000, respectively), and the GGT level was negatively correlated with the TNF-α (r = -0.225, P = 0.001), sOX40L (r = -0.165, P = 0.016), and HSP70 levels (r = -0.178, P = 0.009). Further, the Cr level was negatively correlated with the IL-10 level (r = -0.166, P = 0.015). Logistic regression analysis verified that the BMI (OR  =  1.637, 95%CI: 1.374-1.951, P  =  0.000) and GGT level were significantly higher (OR  =  1.039, 95%CI: 1.020-1.059, P  =  0.000) and that the TNF-α (OR  =  0.998, 95%CI: 0.996-1.000, P  =  0.030) and HSP70 levels were significantly lower (OR  =  1.017, 95%CI: 1.003-1.031, P  =  0.029) in the ALD group than in the non-ALD group. Further, the moderate-to-severe ALD patients had a significantly higher serum CRP level (Or =   1.349, 95%CI: 1.066-1.702, P  =  0.013) and significantly lower HSP60 (OR  =  0.965, 95%CI: 0.938-0.993, P  =  0.014) and HSP70 levels (OR  =  0.978, 95%CI: 0.962-0.995, P  =  0.010) than the mild ALD patients. These results suggest that ALD patients may present with obesity, liver damage, and an imbalanced inflammatory immune response, mainly manifesting as decreased levels of immune inflammatory cytokines. In addition, they suggest that certain liver and kidney function parameters and ALD severity are either positively or negatively correlated with certain inflammatory cytokines. Hence, ALD patients may be at increased risks of obesity- and inflammation-related diseases. Accordingly, to control the inflammatory response, preventative measures for patients with this disease should include weight control and protection of liver and kidney function.

Inflammatory status in human hepatic cirrhosis

This review focuses on new findings about the inflammatory status involved in the development of human liver cirrhosis induced by the two main causes, hepatitis C virus (HCV) infection and chronic alcohol abuse, avoiding results obtained from animal models. When liver is faced to a persistent and/or intense local damage the maintained inflammatory response gives rise to a progressive replacement of normal hepatic tissue by non-functional fibrotic scar. The imbalance between tissue regeneration and fibrosis will determine the outcome toward health recovery or hepatic cirrhosis. In all cases progression toward liver cirrhosis is caused by a dysregulation of mechanisms that govern the balance between activation/homeostasis of the immune system. Detecting differences between the inflammatory status in HCV-induced vs alcohol-induced cirrhosis could be useful to identify specific targets for preventive and therapeutic intervention in each case. Thus, although survival of patients with alcoholic cirrhosis seems to be similar to that of patients with HCV-related cirrhosis (HCV-C), there are important differences in the altered cellular and molecular mechanisms implicated in the progression toward human liver cirrhosis. The predominant features of HCV-C are more related with those that allow viral evasion of the immune defenses, especially although not exclusively, inhibition of interferons secretion, natural killer cells activation and T cell-mediated cytotoxicity. On the contrary, the inflammatory status of alcohol-induced cirrhosis is determined by the combined effect of direct hepatotoxicity of ethanol metabolites and increases of the intestinal permeability, allowing bacteria and bacterial products translocation, into the portal circulation, mesenteric lymph nodes and peritoneal cavity. This phenomenon generates a stronger pro-inflammatory response compared with HCV-related cirrhosis. Hence, therapeutic intervention in HCV-related cirrhosis must be mainly focused to counteract HCV-immune system evasion, while in the case of alcohol-induced cirrhosis it must try to break the inflammatory loop established at the gut-mesenteric lymph nodes-peritoneal-systemic axis.

The detection and role of heat shock protein 70 in various nondisease conditions and disease conditions: a literature review

As an intracellular polypeptide, heat shock protein 70 (HSP70) can be exposed on the plasma membrane and/or released into the circulation. However, the role of HSP70 in various nondisease and disease conditions remains unknown. Quantitative methods for the detection of HSP70 have been used in clinical studies, revealing that an increase in circulating HSP70 is associated with various types of exercise, elderly patients presenting with inflammation, mobile phones, inflammation, sepsis, chronic obstructive pulmonary disease, asthma, carotid intima-media thickness, glutamine-treated ill patients, mortality, diabetes mellitus, active chronic glomerulonephritis, and cancers. Circulating HSP70 decreases with age in humans and in obstructive sleep apnea, arteriosclerosis, atrial fibrillation (AF) following coronary artery bypass surgery, nonalcoholic fatty liver disease, moderate-to-severe alcoholic fatty liver disease, hepatic steatosis, and Helicobacter pylori infection. In conclusion, quantitative methods can be used to detect HSP70, particularly in determining circulating HSP70 levels, using more convenient and rapid screening methods. Studies have shown that changes in HSP70 are associated with various nondisease and disease conditions; thus, HSP70 might be a novel potential biomarker reflecting various nondisease conditions and also the severity of disease conditions. However, the reliability and accuracy, as well as the underlying mechanism, of this relationship remain poorly understood, and large-sample clinical research must be performed to verify the role.

Changes in tumor necrosis factor-α, heat shock protein 70, malondialdehyde, and superoxide dismutase in patients with different severities of alcoholic fatty liver disease: a prospective observational study

The relationships among inflammation, oxidative balance, and the severity of alcoholic fatty liver disease (AFLD) remain unknown. The aim of this study is to explore the relationships among tumor necrosis factor alpha (TNF-α), heat shock protein 70 (HSP70), malondialdehyde (MDA), superoxide dismutase (SOD), and the severity of AFLD.From January 2012 to December 2013, 162 participants were enrolled in this study and divided into 4 groups: 44 cases of mild AFLD (group A), 55 cases of moderate-to-severe AFLD (group B), 44 cases of alcohol consumption without AFLD (group C), and 20 cases of no alcohol consumption without AFLD (group D). A cross-sectional study was conducted by detecting the serum levels of TNF-α, HSP70, MDA, and SOD by enzyme-linked immunosorbent assay.The median serum levels of TNF-α and HSP70 among the 4 groups were statistically significant (P = 0.000 and 0.001, respectively). The median serum levels of TNF-α in groups A and B were significantly lower than in group C (P = 0.002 and 0.000, respectively), and the median serum level of TNF-α in group B was significantly lower than in group D (P = 0.023). In addition, the median serum level of HSP70 in group B was significantly lower than in groups A and C (P = 0.002 and 0.000, respectively), and the median serum level of HSP70 in group C was significantly higher than in group D (P = 0.044). However, the median serum level of MDA in group B was significantly lower than only group C (P = 0.008).Chronic alcohol ingestion without AFLD may result in a significant increase in the circulation of certain inflammatory markers; the severity of AFLD is associated with circulating inflammatory markers, and moderate-to-severe AFLD may result in a more significant reduction of these markers. However, moderate-to-severe AFLD may also result in a significant downregulation of oxidative stress products.

Toll-like receptor-mediated signaling cascade as a regulator of the inflammation network during alcoholic liver disease

Chronic abuse of alcohol leads to various histological abnormalities in the liver. These are conditions collectively known as alcoholic liver disease (ALD). Currently, ALD is considered to be one of the major causes of death worldwide. An impaired intestinal barrier with related endotoxemia is among the various pathogenetic factors. This is mainly characterized by circulating levels of lipopolysaccharide (LPS), considered critical for the onset of intra-hepatic inflammation. This in turn promotes hepatocellular damage and fibrosis in ALD. Elevated levels of LPS exert their effects by binding to Toll-like receptors (TLRs) which are expressed by all liver-resident cells. The activation of TLR signaling triggers an overproduction and release of some cytokines, which promote an autocatalytic cascade of other pro-inflammatory signals. In this review, we provide an overview of the mechanisms that sustain LPS-mediated activation of TLR signaling, reporting current experimental and clinical evidence of its role during inflammation in ALD.

Antitubercular therapy in patients with cirrhosis: Challenges and options

Tuberculosis (TB) has been a human disease for centuries. Its frequency is increased manyfold in patients with liver cirrhosis. The gold standard of TB management is a 6-mo course of isoniazid, rifampicin, pyrazinamide and ethambutol. Although good results are seen with this treatment in general, the management of patients with underlying cirrhosis is a challenge. The underlying depressed immune response results in alterations in many diagnostic tests. The tests used for latent TB have many flaws in this group of patients. Three of four first-line antitubercular drugs are hepatotoxic and baseline liver function is often disrupted in patients with underlying cirrhosis. Frequency of hepatotoxicity is increased in patients with liver cirrhosis, frequently leading to severe liver failure. There are no established guidelines for the treatment of TB in relation to the severity of liver disease. There is no consensus on the frequency of liver function tests required or the cut-off used to define hepatotoxicity. No specific treatment exists for prevention or treatment of hepatotoxicity, making monitoring even more important. A high risk of multidrug-resistant TB is another major worry due to prolonged and interrupted treatment.

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.

Helicobacter pylori induces increased expression of Toll-like receptors and decreased Toll-interacting protein in gastric mucosa that persists throughout gastric carcinogenesis

BACKGROUND

Toll-like receptors (TLR) are essential for Helicobacter pylori (HP) recognition. Their role in the progression of gastric lesions leading to cancer is not established.

AIM

To evaluate for the first time in humans the expression of TLR2, TLR4, and TLR5, as well as the expression of other related molecules in the entire sequence of gastric lesions.

METHODS

Biopsy samples (n = 80, 48% HP+) from normal mucosa, HP gastritis, metaplasia, dysplasia or adenocarcinoma were obtained from 44 patients. mRNA quantification of TLR2, TLR4, TLR5, Toll-interacting protein (TOLLIP), PPAR-γ, NF-κB, TNF-α, COX-1, COX-2, and CDX-2 was performed by real-time RT-PCR. TLR2, TLR4, and TLR5 protein expression was quantified by immunohistochemistry.

RESULTS

When compared to normal mucosa (1.0 arbitrary unit (AU)), HP gastritis presented higher expression of TLR2 (2.23 ± 0.36 AU), TLR4 (1.92 ± 0.40 AU) and TNF-α (2.14 ± 0.50 AU) and lower TOLLIP and PPARγ expression (0.72 ± 0.12 AU, p < .05 all genes). Metaplasia and dysplasia/carcinoma presented higher expression of TLR2 (1.66 ± 0.46 and 1.48 ± 0.20 AU, respectively, p < .05), lower expression of TOLLIP (0.66 ± 0.09 and 0.52 ± 0.04 AU, p < .05) and PPARγ (0.73 ± 0.12 and 0.63 ± 0.10 AU, p < .05). The significant trend for decrease in TOLLIP and PPARγ was associated with increasing levels of CDX-2 from normal mucosa to carcinoma (p < .05), translating that in diffuse and higher TLRs protein expression (p < .05).

CONCLUSION

Gastric carcinogenesis is associated with decreasing levels of TLRs inhibitors and elevated TLRs levels throughout all the spectrum of lesions. Future studies should investigate if modulation of these receptors activity may influence gastric carcinogenesis and tumor progression.

Functional polymorphisms of Toll-like receptors 2 and 4 alter the risk for colorectal carcinoma in Europeans

BACKGROUND

Colon carcinogenesis is associated with increased expression levels of Toll-like receptor 2 and Toll-like receptor 4.

AIM

To determine in a Caucasian population the role of Toll-like receptor 2 and Toll-like receptor 4 polymorphisms in colorectal cancer development.

METHODS

Hospital based multicentre case control study involving 193 colorectal cancer patients and 278 healthy individuals. DNA samples were extracted from blood cells and genotyping of TLR2+597T>C, TLR2-4760T>C, TLR4-3745A>G, TLR2Arg753Gln, TLR4Asp299Gly was performed. Functionality of risk polymorphisms was evaluated through production of TNF-α in cell culture and Toll-like receptors levels quantified by real-time RT-PCR.

RESULTS

TLR2+597CC homozygous had 5-fold decreased risk (odds ratio (OR)=0.21, 95% CI: 0.09-0.50, p<0.001) and TLR4 299Gly homozygous 3-fold increased risk of colorectal cancer (OR=3.30, 95% CI: 1.18-9.28, p=0.015). In stratified analysis, TLR2+597CC genotype protective effect was even higher in overweight individuals (OR=0.17, 95% CI: 0.06-0.53, p<0.001) and in never smokers (OR=0.11, 95% CI: 0.02-0.51, p=0.001). Also, the increased risk effect for TLR4 299Gly homozygous genotype was higher in overweight individuals (OR=8.67, 95% CI: 1.11-87.85, p=0.011). TLR2+597T>C polymorphism conferred 41% less (p=0.03) and TLR4Asp299Gly 65% more TNF-α production (p=0.02) with no differences in Toll-like receptors levels.

CONCLUSION

Functional Toll-like receptor 2 and Toll-like receptor 4 polymorphisms significantly alter the risk to have colorectal cancer. Obesity and smoking may influence the risk for colorectal cancer in individuals presenting these genetic profiles.

Donor polymorphisms of toll-like receptor 4 associated with graft failure in liver transplant recipients

There have been many reports showing significant associations between recipient genetic variants and allograft outcomes, including acute rejection and graft failure, but less is known about the contribution of the donor genotype. We analyzed 37 single-nucleotide polymorphisms (SNPs) within the toll-like receptor 4 (TLR4) gene from deceased donor liver allografts transplanted into 738 recipients to determine their effects on liver graft failure (LGF). Two SNPs exhibited a significant association with LGF after adjustments for donor race and recipient race and corrections for multiple test comparisons: rs11536865 [hazard ratio (HR) = 2.5, P = 0.0003] and rs5030717 (HR = 1.67, P = 0.0008). An additional SNP, rs913930, exhibited a significant association in Caucasian donors (HR = 1.62, P = 0.0006), and 2 SNPs exhibited a suggestive association in African American donors: rs11536865 (HR = 2.45, P = 0.002) and rs5030717 (HR = 2.32, P = 0.002). Additionally, the liver donor risk index (HR = 2.56, 95% confidence interval = 1.54-4.26, P = 0.0003) and the recipient hepatitis C virus (HCV) status (HR = 1.53, 95% confidence interval = 1.04-2.24, P = 0.032) increased the risk of all-cause LGF in a Cox proportional hazards model adjusted for recipient race. Donor polymorphisms in TLR4 could be important factors in modulating TLR4 activity and, therefore, affect the risk of graft loss. Additionally, there is a suggestion of an interaction between polymorphisms within TLR4 and the HCV status.

Increased hepatic expression of TLR2 and TLR4 in the hepatic inflammation-fibrosis-carcinoma sequence

We evaluated expression of TLR2, TLR4 and proinflammatory genes [NF-κB, TNF-α, cyclooxygenase-2 (COX-2)] in liver samples of patients in different stages of liver disease. Fifteen patients with unexplained transaminases elevation (reference group), 22 with viral chronic hepatitis (hepatitis group), 14 with virus-induced severe fibrosis/cirrhosis (cirrhosis group) and 10 with hepatocarcinoma (hepatocarcinoma group) were consecutively included in the study. Quantification of TLR2, TLR4, NF-κB, TNF-α and COX-2 mRNA was done by real-time RT-PCR and TLR2 and TLR4 protein expression was evaluated by immunohistochemistry. Compared with reference, TLR2 and TLR4 mRNA was increased in hepatitis (TLR2: 2.66 ± 0.69; TLR4: 3.11 ± 0.79; P < 0.05) and cirrhosis (TLR2: 2.14 ± 0.5; TLR4: 1.74 ± 0.27; P < 0.05) and decreased in hepatocarcinoma (TLR2: 0.48 ± 0.15; TLR4: 0.54 ± 0.10; P < 0.05). This associated with increased TNF-α and COX-2 mRNA in hepatitis (TNF-α: 3.24 ± 0.79; COX-2: 2.47 ± 0.36; P < 0.05) and cirrhosis (TNF-α: 1.73 ± 0.28; COX-2: 1.8 ± 0.35, P < 0.05), whereas NF-κB mRNA was increased in hepatitis (2.42 ± 0.31; P < 0.05) and unchanged in cirrhosis (1.34 ± 0.17; P = 0.3). Hepatocarcinoma presented increased COX-2 mRNA (1.63 ± 0.15; P < 0.05) and maintained (at decreased levels) mRNA of NF-κB (0.52 ± 0.12) and TNF-α (0.52 ± 0.12; P < 0.05, all genes). Immunohistochemistry confirmed increased expression of TLR2 and TLR4 in hepatitis and cirrhosis and maintained expression in hepatocarcinoma. Upregulation of TLR2, TLR4 and their proinflammatory mediators is associated with virus-induced hepatic IFC sequence.

Role of Toll-like receptor (TLR) 2 in experimental Bacillus cereus endophthalmitis

Bacillus cereus causes a uniquely rapid and blinding intraocular infection, endophthalmitis. B. cereus replicates in the eye, synthesizes numerous toxins, and incites explosive intraocular inflammation. The mechanisms involved in the rapid and explosive intraocular immune response have not been addressed. Because Toll-like receptors (TLRs) are integral to the initial recognition of organisms during infection, we hypothesized that the uniquely explosive immune response observed during B. cereus endophthalmitis is directly influenced by the presence of TLR2, a known gram-positive pathogen recognition receptor. To address this hypothesis, we compared the courses of experimental B. cereus endophthalmitis in wild type C57BL/6J mice to that of age-matched homozygous TLR2(-/-) mice. Output parameters included analysis of bacterial growth, inflammatory cell (PMN) infiltration, cytokine/chemokine kinetics, retinal function testing, and histology, with N≥4 eyes/assay/time point/mouse strain. B. cereus grew at similar rates to10(8) CFU/eye by 12 h, regardless of the mouse strain. Retinal function was preserved to a greater degree in infected TLR2(-/-) eyes compared to that of infected wild type eyes, but infected eyes of both mouse strains lost significant function. Retinal architecture was preserved in infected TLR2(-/-) eyes, with limited retinal and vitreal cellular infiltration compared to that of infected wild type eyes. Ocular myeloperoxidase activities corroborated these results. In general, TNFα, IFNγ, IL6, and KC were detected in greater concentrations in infected wild type eyes than in infected TLR2(-/-) eyes. The absence of TLR2 resulted in decreased intraocular proinflammatory cytokine/chemokine levels and altered recruitment of inflammatory cells into the eye, resulting in less intraocular inflammation and preservation of retinal architecture, and a slightly greater degree of retinal function. These results demonstrate TLR2 is an important component of the initial ocular response to B. cereus endophthalmitis.

Bench-to-beside review: acute-on-chronic liver failure - linking the gut, liver and systemic circulation

The concept of acute-on-chronic liver failure (ACLF) was introduced recently to describe a subset of patients with chronic liver disease presenting with profound deterioration of liver function and rapidly evolving multi-organ failure. ACLF is frequently accompanied by the development of severe inflammatory response syndrome and has a high mortality. To date, treatment options are limited and exclusively supportive. Over the last few years, some insights have been generated in the pathophysiology of ACLF. A key role for the interaction of innate immune dysfunction, enhanced bacterial translocation from the gut, and circulatory dysfunction has been proposed. In this respect, therapeutic strategies have been examined, with variable success, in experimental studies in animals and humans. This review focuses on potentially relevant pathophysiological elements in the development of ACLF and points out promising treatment modalities in ACLF.