A Flexible Ammonia Gas Sensor Based on a Grafted Polyaniline Grown on a Polyethylene Terephthalate Film.

A novel NH3 gas sensor is introduced, employing polyaniline (PANI) with a unique structure called a graft film. The preparation method was simple: polydopamine (PD) was coated on a flexible polyethylene terephthalate (PET) film and PANI graft chains were grown on its surface. This distinctive three-layer sensor showed a response value of 12 for 50 ppm NH3 in a dry atmosphere at 50 °C. This value surpasses those of previously reported sensors using structurally controlled PANI films. Additionally, it is on par with sensors that combine PANI with metal oxide semiconductors or carbon materials, the high sensitivity of which have been reported. To confirm our film's potential as a flexible sensor, the effect of bending on the its characteristics was investigated. This revealed that although bending decreased the response value, it had no effect on the response time or recovery. This indicated that the sensor film itself was not broken by bending and had sufficient mechanical strength.

C-C motif chemokine receptor 9 regulates obesity-induced insulin resistance via inflammation of the small intestine in mice.

AIMS/HYPOTHESIS: Accumulation of adipose tissue macrophages is considered pivotal in the development of obesity-associated inflammation and insulin resistance. In addition, recent studies suggest an involvement of the intestine as the primary organ in inducing hyperglycaemia and insulin resistance. We have reported that the C-C motif chemokine receptor (CCR) CCR9 is associated with intestinal immunity and has a pathogenic role in various liver diseases. However, its contribution to type 2 diabetes is unknown. In the current study, we aimed to clarify the involvement of CCR9 in the pathology of type 2 diabetes and the potential underlying mechanisms. METHODS: To elucidate how CCR9 affects the development of metabolic phenotypes, we examined the impact of CCR9 deficiency on the pathogenesis of type 2 diabetes using male C57BL/6J (wild-type [WT]) and CCR9-deficient (CCR9 knockout [KO]) mice fed a 60% high-fat diet (HFD) for 12 weeks. RESULTS: WT and Ccr9KO mice fed an HFD exhibited a comparable weight gain; however, glucose tolerance and insulin resistance were significantly improved in Ccr9KO mice. Moreover, visceral adipose tissue (VAT) and the liver of Ccr9KO mice presented with less inflammation and increased expression of glucose metabolism-related genes than WT mice. Ccr9 and Ccl25 expression were specifically higher in the small intestine but was not altered by HFD feeding and type 2 diabetes development. Accumulation of IFN-γ-producing CD4+ T lymphocytes and increased intestinal permeability in the small intestine was observed in WT mice following HFD feeding, but these changes were suppressed in HFD-fed Ccr9KO mice. Adoptive transfer of gut-tropic CCR9-expressing T lymphocytes partially reversed the favourable glucose tolerance found in Ccr9KO mice via exacerbated inflammation in the small intestine and VAT. CONCLUSIONS/INTERPRETATION: CCR9 plays a central role in the pathogenesis of type 2 diabetes by inducing an inflammatory shift in the small intestine. Our findings support CCR9 as a new therapeutic target for type 2 diabetes via the gut-VAT-liver axis.

Role of CC chemokine receptor 9 in the progression of murine and human non-alcoholic steatohepatitis.

BACKGROUND & AIMS: The number of patients with non-alcoholic steatohepatitis (NASH) is increasing globally. Recently, specific chemokine receptors have garnered interest as therapeutic targets in NASH. This is the first report to examine the role of the C-C chemokine receptor 9 (CCR9)/C-C chemokine receptor ligand 25 (CCL25) axis, and to reveal its therapeutic potential in NASH. METHODS: Patients with biopsy-proven non-alcoholic liver disease (NAFLD) were recruited and their serum and hepatic chemokine expression was examined. Furthermore, wild-type (WT) and Ccr9-/- mice were fed a high-fat high-cholesterol (HFHC) diet for 24 weeks to establish NASH. RESULTS: Serum CCL25, and hepatic CCR9 and CCL25 expression levels were increased in patients with NASH compared to healthy volunteers. Furthermore, Ccr9-/- mice were protected from HFHC diet-induced NASH progression both serologically and histologically. Flow cytometry and immunohistochemistry analysis showed that CCR9+CD11b+ inflammatory macrophages accumulated in the inflamed livers of HFHC diet-fed mice, while the number was reduced in Ccr9-/- mice. Consistent with human NASH livers, CCR9 was also expressed on hepatic stellate cells (HSCs) in mice with NASH, while CCR9-deficient HSCs showed less fibrogenic potential in vitro. Administration of a CCR9 antagonist hampered further fibrosis progression in mice with NASH, supporting its potential clinical application. Finally, we showed that CCR9 blockade attenuated the development of NAFLD-related hepatocellular carcinoma in HF diet-fed mice injected with diethylnitrosamine. CONCLUSIONS: These results highlight the role of the CCR9/CCL25 axis on macrophage recruitment and fibrosis formation in a murine NASH model, providing new insights into therapeutic strategies for NASH. LAY SUMMARY: Herein, we show that a specific chemokine axis involving a receptor (CCR9) and its ligand (CCL25) contributes to the progression of non-alcoholic steatohepatitis and carcinogenesis in humans and mice. Furthermore, treatment with a CCR9 antagonist ameliorates the development of steatohepatitis and holds promise for the treatment of patients with non-alcoholic steatohepatitis.

A Highly Sensitive Ammonia Gas Sensor Using Micrometer-Sized Core-Shell-Type Spherical Polyaniline Particles.

A highly sensitive NH3 gas sensor based on micrometer-sized polyaniline (PANI) spheres was successfully fabricated. The PANI microspheres were prepared via a facile in situ chemical oxidation polymerization in a polystyrene microsphere dispersion solution, resulting in a core-shell structure. The sensor response increased as the diameter of the microspheres increased. The PSt@PANI(4.5) sensor, which had microspheres with a 4.5 µm average diameter, showed the largest response value of 77 for 100 ppm dry NH3 gas at 30 °C, which was 20 times that of the PANI-deposited film-based sensor. Even considering measurement error, the calculated detection limit was 46 ppb. A possible reason for why high sensitivity was achieved is simply the use of micrometer-sized PANI spherical particles. This research succeeded in providing a new and simple technology for developing a high-sensitivity NH3 gas sensor that operates at room temperature.

Clinical implications with tolvaptan on monitored bioimpedance-defined fluid status in patients with cirrhotic ascites: an observational study.

BACKGROUND: Prognostic value or clinical implications of fluid status monitoring in liver cirrhosis are not fully elucidated. Tolvaptan, an orally available, selective vasopressin V2-receptor antagonist approved for hyponatremia in the United States and European Union. It is also used for cirrhotic ascites at a relatively low dose (3.75 mg to 7.5 mg) in Japan, exerts its diuretic function by excreting electrolyte-free water. We hypothesized that bioimpedance-defined dynamic changes in fluid status allow prediction of response of V2 antagonism and survival in cirrhotic patients. METHODS: In this prospective observational study, 30 patients with decompensated liver cirrhosis who were unresponsive to conventional diuretics were enrolled. Detailed serial changes of body composition that were assessed by using non-invasive bioimpedance analysis (BIA) devices, along with biochemical studies, were monitored at 5 time points. RESULTS: Sixteen patients were classified as short-term responders (53%). Rapid and early decrease of BIA-defined intracellular water, as soon as 6 h after the first dose (ΔICWBIA%-6 h), significantly discriminated responders from non-responders (AUC = 0.97, P < 0.0001). ΔICWBIA%-6 h was highly correlated with the change of BIA-derived phase angle of trunk, e.g. reduced body reactance operated at 50 kHz after 24 h of the first dose of tolvaptan. Lower baseline blood urea nitrogen and lower serum aldosterone were predictive of a rapid and early decrease of ICWBIA. A rapid and early decrease of ICWBIA in response to tolvaptan was also predictive of a better transplant-free survival. CONCLUSIONS: BIA-defined water compartment monitoring may help predict short-term efficacy and survival in decompensated cirrhotic patients treated with tolvaptan.

Humidity-Resistive Optical NO Gas Sensor Devices Based on Cobalt Tetraphenylporphyrin Dispersed in Hydrophobic Polymer Matrix.

We report on an optical nitrogen oxide (NO) gas sensor device using cobalt tetraphenylporphyrin (CoTPP) dispersed in three kinds of hydrophobic polymer film matrix (polystyrene (PSt), ethylcellulose (EC), and polycyclohexyl methacrylate (PCHMA)) to improve humidity resistance. Our approach is very effective because it allows us to achieve not only high humidity resistance, but also a more than sixfold increase in sensitivity compared with CoTPP film due to the high dispersion of CoTPP in the polymer film. The limit of detection was calculated as 33 ppb for the CoTPP-dispersed EC film, which is lower than that of CoTPP film (92 ppb).

Liposomalization of oxaliplatin induces skin accumulation of it, but negligible skin toxicity.

Liposomalization causes alteration of the pharmacokinetics of encapsulated drugs, and allows delivery to tumor tissues through passive targeting via an enhanced permeation and retention (EPR) effect. PEGylated liposomal doxorubicin (Doxil®, Lipo-DXR), a representative liposomal drug, is well-known to reduce cardiotoxicity and increase the anti-tumor activity of DXR, but to induce the hand-foot syndrome (HFS) as a result of skin DXR accumulation, which is one of its severe adverse effects. We have developed a new liposomal preparation of oxaliplatin (l-OHP), an important anti-tumor drug for treatment of colorectal cancer, using PEGylated liposomes (Lipo-l-OHP), and showed that Lipo-l-OHP exhibits increased anti-tumor activity in tumor-bearing mice compared to the original preparation of l-OHP. However, whether Lipo-l-OHP causes HFS-like skin toxicity similar to Lipo-DXR remains to be determined. Administration of Lipo-l-OHP promoted accumulation of platinum in rat hind paws, however, it caused negligible morphological and histological alterations on the plantar surface of the paws. Administration of DiI-labeled empty PEGylated liposomes gave almost the same distribution profile of dyes into the dermis of hind paws with DXR as in the case of Lipo-DXR. Treatment with Lipo-l-OHP, Lipo-DXR, DiI-labeled empty PEGylated liposomes or empty PEGylated liposomes caused migration of CD68+ macrophages into the dermis of hind paws. These findings suggest that the skin toxicity on administration of liposomalized drugs is reflected in the proinflammatory characteristics of encapsulated drugs, and indicate that Lipo-l-OHP with a higher anti-cancer effect and no HFS may be an outstanding l-OHP preparation leading to an improved quality of life of cancer patients.

Recovery from anemia and leukocytopenia after abstinence in Japanese alcoholic men and their genetic polymorphisms of alcohol dehydrogenase-1B and aldehyde dehydrogenase-2.

BACKGROUND: The combination of the fast-metabolizing alcohol dehydrogenase-1B (ADH1B*2 allele) and inactive heterozygous aldehyde dehydrogenase-2 (ALDH2*1/*2) increases susceptibility to macrocytic anemia and leukocytopenia in alcoholics due to severe acetaldehydemia. More than half of Japanese drinkers with esophageal cancer have this genotype combination. METHODS: To assess the recovery of hematologic abnormalities after drinking cessation, changes in blood erythrocyte indices and leukocyte count during 8-week hospital stay were evaluated in 925 Japanese alcoholic men. We used four categories in ascending order for high blood acetaldehyde exposure from drinking: A, ADH1B*1/*1 plus ALDH2*1/*1; B, ADH1B*2 plus ALDH2*1/*1; C, ADH1B*1/*1 plus ALDH2*1/*2; and D, ADH1B*2 plus ALDH2*1/*2. RESULTS: Mean values of hemoglobin and hematocrit were the lowest, and those of mean corpuscular volume (MCV) were markedly the highest in the D group on admission, and returning toward normal after abstinence, but the inter-group differences remained significant throughout the 8 weeks. The mean leukocyte count was the lowest in the D group on admission, but increased during 4-week abstinence when the inter-group differences were no longer significant. Frequencies of MCV ≥110 fl (50.5%), hemoglobin levels <11.5 g/dL (32.7%), hemoglobin levels <10.0 g/dL (9.9%) and leukocytopenia <4000/µL (22.8%) were the highest in the D group on the admission day and decreased at the 4-week abstinence (28.7%, 18.8%, 4.0% and 7.9%, respectively). The inter-group differences in frequencies of the severe anemia and leukocytopenia disappeared after 4-week abstinence. CONCLUSIONS: Drinking cessation before surgery and/or chemoradiation treatment for esophageal cancer may be effective for recovery from anemia and leukocytopenia in drinkers belonging to the D group.

Vertically Oriented Metallic Heterodimer Array Semiembedded in Flat Conductive Carbon Film for Electrochemical Application.

General synthesis of a highly oriented metallic heterodimer array based on a selective electrodeposition technique onto a metal nanoparticle-embedded carbon film is proposed, which enables the preparation of heterodimers with a wide variety of metal combinations. This method requires no surfactant, capping agent, organic solvent, or heat treatment. As a representative metal combination, a nickel (Ni)/palladium (Pd) heterodimer array was prepared by selective electrodeposition of Ni nanoparticles (Ni NPs) on top of partially exposed Pd NPs embedded in carbon film electrodes fabricated by a cosputtering technique. Such a selective electrodeposition becomes possible by utilizing the difference in electrodeposition overpotentials between carbon and Pd NP surfaces. X-ray photoelectron spectroscopy revealed a charge transfer from Ni NPs to Pd NPs, implying that the catalytic and optical properties can be expected to be controllable. The formed heterodimer array structure was mechanically stable against ultrasonication in ethanol for over 1 h because most parts of the Pd NPs were tightly embedded in the carbon film. After conversion from Ni to nickel hydroxide (Ni(OH)2), the electrode showed high electrocatalytic activity toward glucose oxidation, with a higher turnover rate and lower overpotential compared to Ni(OH)2 electrodeposited on pure carbon film electrodes.

Hybrid Carbon Film Electrodes for Electroanalysis.

Carbon materials have been widely used for electrochemical analysis and include carbon nanotubes, graphene, and boron-doped diamond electrodes in addition to conventional carbon electrodes, such as those made of glassy carbon and graphite. Of the carbon-based electrodes, carbon film has advantages because it can be fabricated reproducibly and micro- or nanofabricated into electrodes with a wide range of shapes and sizes. Here, we report two categories of hybrid-type carbon film electrodes for mainly electroanalytical applications. The first category consists of carbon films doped or surface terminated with other atoms such as nitrogen, oxygen and fluorine, which can control surface hydrophilicity and lipophilicity or electrocatalytic performance, and are used to detect various electroactive biochemicals. The second category comprises metal nanoparticles embedded in carbon film electrodes fabricated by co-sputtering, which exhibits high electrocatalytic activity for environmental and biological samples including toxic heavy metal ions and clinical sugar markers, which are difficult to detect at pure carbon-based electrodes.

Supporting effects of a N-doped carbon film electrode on an electrodeposited Ni@Ni(OH)2 core-shell nanocatalyst in accelerating electrocatalytic oxidation of oligosaccharides.

The supporting effect of a N-doped carbon film induced superior crystallinity in electrodeposited Ni@Ni(OH)2 core-shell nanoparticles. This improvement resulted in a much higher regeneration rate of catalytic sites (NiOOH), leading to higher oxidation currents of sugars. Also, the overpotential of the maltopentaose (G5) oxidation reaction decreased significantly, probably due to the effect of the electrostatic interaction between NPs and G5.

Acetaldehyde exposure underlies functional defects in monocytes induced by excessive alcohol consumption.

Increased intestinal permeability and hepatic macrophage activation by endotoxins are involved in alcohol-induced liver injury pathogenesis. Long-term alcohol exposure conversely induces endotoxin immune tolerance; however, the precise mechanism and reversibility are unclear. Seventy-two alcohol-dependent patients with alcohol dehydrogenase-1B (ADH1B, rs1229984) and aldehyde dehydrogenase-2 (ALDH2, rs671) gene polymorphisms admitted for alcohol abstinence were enrolled. Blood and fecal samples were collected on admission and 4 weeks after alcohol cessation and were sequentially analyzed. Wild-type and ALDH2*2 transgenic mice were used to examine the effect of acetaldehyde exposure on liver immune responses. The productivity of inflammatory cytokines of peripheral CD14+ monocytes in response to LPS stimulation was significantly suppressed in alcohol dependent patients on admission relative to that in healthy controls, which was partially restored by alcohol abstinence with little impact on the gut microbiota composition. Notably, immune suppression was associated with ALDH2/ADH1B gene polymorphisms, and patients with a combination of ALDH2*1/*2 and ADH1B*2 genotypes, the most acetaldehyde-exposed group, demonstrated a deeply suppressed phenotype, suggesting a direct role of acetaldehyde. In vitro LPS and malondialdehyde-acetaldehyde adducted protein stimulation induced direct cytotoxicity on monocytes derived from healthy controls, and a second LPS stimulation suppressed the inflammatory cytokines production. Consistently, hepatic macrophages of ethanol-administered ALDH2*2 transgenic mice exhibited suppressed inflammatory cytokines production in response to LPS compared to that in wild-type mice, reinforcing the contribution of acetaldehyde to liver macrophage function. These results collectively provide new perspectives on the systemic influence of excessive alcohol consumption based on alcohol-metabolizing enzyme genetic polymorphisms.

Hepatic Adenosine Triphosphate Reduction Through the Short-Chain Fatty Acids-Peroxisome Proliferator-Activated Receptor γ-Uncoupling Protein 2 Axis Alleviates Immune-Mediated Acute Hepatitis in Inulin-Supplemented Mice.

How liver tolerance is disrupted in immune-mediated liver injury is currently unclear. There is also insufficient information available regarding susceptibility, precipitation, escalation, and perpetuation of autoimmune hepatitis. To explore how dietary fiber influences hepatic damage, we applied the concanavalin A (ConA)-induced acute immune-mediated liver injury model in mice fed a diet supplemented with 6.8% inulin, a water-soluble fermentable fiber. Twelve hours after ConA administration, inulin-supplemented diet-fed mice demonstrated significantly alleviated hepatic damage histologically and serologically, with down-regulation of hepatic interferon-γ and tumor necrosis factor and reduced myeloperoxidase (MPO)-producing neutrophil infiltration. Preconditioning with an inulin-supplemented diet for 2 weeks significantly reduced hepatic adenosine triphosphate (ATP) content; suramin, a purinergic P2 receptor antagonist, abolished the protective effect. Of note, the portal plasma derived from mice fed the inulin-supplemented diet significantly alleviated ConA-induced immune-mediated liver injury. Mechanistically, increased portal short-chain fatty acid (SCFA) levels, such as those of acetate and butyrate, by inulin supplementation leads to up-regulation of hepatic γ-type peroxisome proliferator-activated receptor (Pparg) and uncoupling protein 2 (Ucp2), which uncouples mitochondrial ATP synthesis downstream of PPARγ. Pparg down-regulating small interfering RNA cancelled the protective effect of inulin supplementation against MPO-producing neutrophil infiltration and the subsequent immune-mediated liver injury, suggesting that the SCFA-PPARγ-UCP2 axis plays a key role in the protective effect by inulin supplementation. Moreover, significant changes in the gut microbiota, including increased operational taxonomic units in genera Akkermansia and Allobaculum, also characterized the protective effect of the inulin-supplemented diet. Conclusion: There is a possible unraveled etiopathophysiological link between the maintenance of liver tolerance and dietary fiber. The SCFA-PPARγ-UCP2 axis may provide therapeutic targets for immune-mediated liver injury in the future.

Moderate alcohol consumption is not associated with subclinical cardiovascular damage but with hepatic fibrosis in non-alcoholic fatty liver disease.

BACKGROUND: Moderate alcohol consumption is believed to be associated with reduced mortality from cardiovascular disease (CVD) in the general population. This cross-sectional study aimed to comprehensively examine the association between alcohol consumption and subclinical cardiovascular damage or hepatic fibrosis in non-alcoholic fatty liver disease (NAFLD). METHODS: Subjects with NAFLD without a history of heart disease were extracted from 977 consecutive examinees who completed health checkups and optional cardiovascular examinations. Subclinical cardiovascular damage was assessed by coronary artery calcification (CAC), carotid artery ultrasound, and brachial-ankle pulse wave velocity (ba-PWV). CAC scores were classified into three grades (0, ≤100, and >100) by Agatston's method. Alcohol consumption was divided into three groups [Non-drinking (G0); Light (G1), 0.1-6.9 drinks/week; Moderate (G2), 7-20.9 drinks/week for men and 7-13.9 drinks/week for women]. Noninvasive markers (FIB-4, Fibrosis-4; NFS, NAFLD fibrosis score) were calculated for assessment of hepatic fibrosis and classified into low and intermediate-high grade. RESULTS: The overall mean age was 60.2 years and males were 200 (74.6%) among 268 subjects with NAFLD. Number (%) of G0, G1, and G2 were 102 (38.1%), 103 (38.4%), and 63 (23.5%). Binary logistic regression analysis showed no significant difference between G0 and G1, or G0 and G2 in any of the above subclinical cardiovascular damages (CAC score >0, or CAC score >100, carotid plaque +, intima-media thickness ≥1.1 mm, and ba-PWV >1400 cm/s). However, only G2 had a significant association with intermediate-high grade of FIB-4 or NFS [odds ratio (95% confidence intervals), p value: 1.871 (1.209-2.893), p = 0.005; 2.910 (1.715-4.939), p = 0.000], compared to G0. CONCLUSIONS: Non-heavy drinking might not reduce the risk of CVD in NAFLD subjects. On the contrary, even moderate drinking could promote hepatic fibrosis. Thus, NAFLD drinkers should not be recommended for even a moderate amount of alcohol.

Increased electrode activity during geosmin oxidation provided by Pt nanoparticle-embedded nanocarbon film.

The musty odor compound geosmin was electrochemically detected by using Pt nanoparticle (PtNP)-embedded nanocarbon (Pt-C) films formed with unbalanced magnetron (UBM) co-sputtering. The sputtered Pt components formed NPs (typically 1.53-4.75 nm in diameter) spontaneously in the carbon films, owing to the poor intermiscibility of Pt with carbon. The surface concentrations of PtNPs embedded in the nanocarbon film were widely controllable (Pt = 4.8-35.9 at%) by regulating the target powers of the Pt and carbon individually. The obtained film had a flat surface (Ra = 0.17-0.18 nm) despite the fact the PtNPs were partially exposed at the surface. Compared with a Pt film electrode, some Pt-C films exhibited higher electrode activity against geosmin although the surface Pt concentrations of these Pt-C films were much lower than that of the Pt film electrode, thanks to the wider potential window and lower background current that resulted from the ultraflat and stable carbon-based film prepared by UBM co-sputtering. Computational experiments revealed that the theoretical oxidation potential (Eox) value for geosmin was relatively similar to that obtained in electrochemical experiments using our Pt-C film electrode. Moreover, we also theoretically estimated the possible oxidation site of geosmin molecules and the advantage of the NP shape of the electroactive Pt parts as regards the electrochemical oxidation of geosmin. We successfully used the Pt-C film (10.6 at%) electrode to detect geosmin in combination with HPLC at a low detection limit of 100 ng L-1.

Plasmacytoid dendritic cells protect against immune-mediated acute liver injury via IL-35.

Acute liver failure (ALF) is a life-threatening condition, and liver transplantation is the only therapeutic option. Although immune dysregulation is central to its pathogenesis, the precise mechanism remains unclear. Here, we show that the number of peripheral and hepatic plasmacytoid DCs (pDCs) decrease during acute liver injury in both humans and mice. Selective depletion of pDCs in Siglechdtr/+ mice exacerbated concanavalin A-induced acute liver injury. In contrast, adoptively transferred BM-derived pDCs preferentially accumulated in the inflamed liver and protected against liver injury. This protective effect was independent of TLR7 and TLR9 signaling, since a similar effect occurred following transfer of MyD88-deficient pDCs. Alternatively, we found an unexpected immunosuppressive role of pDCs in an IL-35-dependent manner. Both Il12a and Ebi3, heterodimeric components of IL-35, were highly expressed in transferred pDCs and CD4+CD25+ Tregs. However, the protective effect of pDC transfer was completely lost in mice depleted of Tregs by anti-CD25 antibody. Moreover, pDCs derived from IL-35-deficient mice had less of a protective effect both in vivo and in vitro even in the presence of Tregs. These results highlight a unique aspect of pDCs in association with Tregs, serving as a guide for immunotherapeutic options in ALF.

Liver Fibrosis Markers Improve Prediction of Outcome in Non-Acetaminophen-Associated Acute Liver Failure.

A prognostic system for acute liver failure (ALF) with a higher predictive value is urgently needed. The role of extracellular matrix (ECM) remodeling in ALF has not been fully elucidated. We hypothesized that serologic fibrosis markers, which reflect ECM remodeling, are predictive of ALF outcome at first presentation. This observational study included 110 patients with acute liver dysfunction, of which 73 had non-acetaminophen-associated ALF (NAA-ALF). We evaluated serum levels of hyaluronic acid, 7S domain of type IV collagen (4COL7S), and Wisteria floribunda agglutinin-positive Mac-2-binding protein at first presentation to a tertiary center. Serologic fibrosis markers were significantly higher in NAA-ALF compared with acute hepatitis. Elevated hyaluronic acid and 4COL7S levels at first presentation correlated significantly with worse clinical outcomes. 4COL7S, along with age, ammonia, and the Model for End-Stage Liver Disease (MELD) score, was a significant prognostic factor in multivariate analysis; 4COL7S correlated significantly with coagulopathy, decreased hepatic synthetic functions, advanced hepatic encephalopathy, and liver atrophy and also predicted 180-day transplant-free survival. Cox regression models incorporating 4COL7S with the MELD system had profoundly improved predictive values that significantly surpassed the MELD system alone. Conclusion: Elevation of serologic fibrosis markers reflecting ECM remodeling in NAA-ALF predicted a worse clinical outcome. Incorporation of 4COL7S at first presentation to a transplant center improves the specificity while retaining the sensitivity of the MELD system. External validation of a fibrosis marker as part of a clinical prediction tool in ALF warrants further investigation.

Intestinal barrier regulates immune responses in the liver via IL-10-producing macrophages.

The gut-liver axis is of clinical importance as a potential therapeutic target in a wide range of liver diseases; however, the mechanisms underlying interactions between microbial products and immune responses in the liver remain unknown. In this study, we demonstrated that IL-10-producing macrophages contribute to immune tolerance in the inflamed liver under intestinal barrier disruption in a murine tandem model of dextran sulfate sodium (DSS) colitis and concanavalin A (Con A) hepatitis. Intestinal barrier disruption protected mice from subsequent liver injury, and the severity of colitis directly affected susceptibility to such injury. The protective effect of DSS-Con A was canceled in gut-sterilized mice, suggesting that gut microbiota play a substantial role in this process. Altered gut microbiota and their metabolites, along with a disrupted intestinal barrier, directly gave rise to immunological permissiveness in the inflamed liver. We identified 1-methylnicotinamide (1-MNA) as a candidate metabolite capable of suppressing liver injury with the potential to induce IL-10-producing macrophages. Consistently, expression of nicotinamide N-methyltransferase, which converts nicotinamide to 1-MNA, was upregulated in the liver of DSS-Con A mice, and this effect was abrogated by gut sterilization. Collectively, our results provide a mechanistic insight into the regulation of immunological balance in the liver via the gut-liver axis.

On-treatment decrease of NKG2D correlates to early emergence of clinically evident hepatocellular carcinoma after interferon-free therapy for chronic hepatitis C.

BACKGROUND AND AIMS: Interferon (IFN)- free direct antiviral agents (DAAs) with rapid HCV eradication might evoke immunological reconstitutions, and some early recurrences of HCC after IFN-free DAAs have been reported. This study aimed to investigate whether natural killer group 2, member D (NKG2D) predicts early emergence of HCC after IFN-free DAAs. METHODS: We conducted a clinical practice-based observational study of 101 patients infected with genotype 1 HCV who received IFN-free (DAAs), and stratified them into those who did or did not develop early (i.e., during the 6-month surveillance period following treatment.) recurrence or occurrence of clinically evident HCC. We also analyzed the peripheral blood mononuclear cells, both before treatment and at end of treatment (EOT), of 24 of the patients who received IFN-free DAAs, and 16 who received IFN-combined protease inhibitor. RESULTS: We found early emergence of clinically evident HCC after IFN-free DAAs in 12 (12%) patients. Higher pre-treatment NKG2D expression, higher FIB-4 score, previous HCC history and failure to achieve sustained viral response were significant factors correlating to early HCC emergence. After IFN-free DAAs, a rapid decrease of NKG2D at EOT correlated with early HCC emergence in the IFN-free DAA-treated patients, but not in patients treated with the IFN-combined regimen. The decrease of NKG2D until EOT was predictive of early HCC emergence at a cut-off of -52% (AUC = 0.92). CONCLUSIONS: On-treatment decrease of NKG2D may be a useful predictor of early emerging HCC in patients treated with IFN-free DAAs.

Commensal Lactobacillus Controls Immune Tolerance during Acute Liver Injury in Mice.

Gut-derived microbial antigens trigger the innate immune system during acute liver injury. During recovery, regulatory immunity plays a role in suppressing inflammation; however, the precise mechanism underlying this process remains obscure. Here, we find that recruitment of immune-regulatory classical dendritic cells (cDCs) is crucial for liver tolerance in concanavalin A-induced acute liver injury. Acute liver injury resulted in enrichment of commensal Lactobacillus in the gut. Notably, Lactobacillus activated IL-22 production by gut innate lymphoid cells and raised systemic IL-22 levels. Gut-derived IL-22 enhanced mucosal barrier function and promoted the recruitment of regulatory cDCs to the liver. These cDCs produced IL-10 and TGF-ß through TLR9 activation, preventing further liver inflammation. Collectively, our results indicate that beneficial gut microbes influence tolerogenic immune responses in the liver. Therefore, modulation of the gut microbiota might be a potential option to regulate liver tolerance.