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The liver is an essential organ for regulating innate and acquired immunity. We hypothesized that the pre-treatment hepatic function affects the clinical outcome of immune checkpoint inhibitors (ICIs) in non-small cell lung cancer (NSCLC). We analyzed 140 patients with NSCLC who received ICIs. We investigated the association between pre-treatment liver function, assessed using the albumin-bilirubin (ALBI) grade, and clinical outcomes in univariate, multivariate, and propensity score matching analyses. Patients were divided into four grades according to pre-treatment liver function. Eighty-eight patients had good hepatic reserve (ALBI grade 1 or 2a), whereas 52 patients had poor hepatic reserve (ALBI grade 2b or 3). In the univariate Kaplan-Meier analysis, the ALBI grade 1, 2a group had a significantly prolonged progression-free survival (PFS, 5.3 versus 2.5 months, p = 0.0019) and overall survival (OS, 19.6 vs. 6.2 months, p = 0.0002). These results were consistent, regardless of whether the analysis was performed in patients with a performance status of 0 or 1 at pre-treatment (N = 124) or in those selected using propensity score matching (N = 76). In the multivariate analysis, pre-treatment ALBI grade was an independent prognostic factor for both PFS (hazard ratio [HR] 0.57, 95% confidence interval [95% CI] 0.38-0.86, p = 0.007) and OS (HR 0.45, 95% CI 0.29-0.72, p = 0.001). Our results suggest that pre-treatment hepatic function assessed by ALBI grade could be an essential biomarker for predicting the efficacy of treatment with ICIs in NSCLC., (© 2021. The Author(s).)

Foxp3+ regulatory T (Treg) cells are pivotal in maintaining immunological self-tolerance and tissue homeostasis; however, it remains unclear how tissue Treg cells respond to liver injury and regulate chronic inflammation, which can cause liver fibrosis. We report here that hepatic Treg cells play a critical role in preventing liver pathology by suppressing inflammatory cellular immunity that can promote liver damage and fibrosis. Chronic liver inflammation induced by injections of carbon tetrachloride (CCl 4 ) led to preferential expansion of hepatic Treg cells that prevented liver fibrosis. In contrast, depletion of Treg cells in the CCl 4 -induced liver fibrosis model exacerbated the severity of liver pathology. Treg depletion unleashed tissue cellular immunity and drove the activation and expansion of the pro-fibrotic IL-4-producing T helper 2 cells, as well as CCR2 high Ly-6C high inflammatory monocytes/macrophages in the inflamed liver. Although Treg expression of amphiregulin plays a key role in tissue remodeling and repair in various inflammation models, amphiregulin from hepatic Treg cells, the largest producer among liver immune cells, was dispensable for maintaining liver homeostasis and preventing liver fibrosis during CCl 4 -induced chronic inflammation. Our results indicate that Treg cells control chronic liver inflammation and fibrosis by regulating the aberrant activation and functions of immune effector cells. Harnessing Treg functions, which effectively regulate tissue cellular immunity, may be a therapeutic strategy for preventing and treating liver fibrosis., (Copyright © 2020 Ikeno, Ohara, Takeuchi, Watanabe, Kondoh, Taura, Uemoto and Hirota.)

This report describes the autopsy case of a 4-year-old boy who died from hepatic hemorrhage and rupture caused by peliosis hepatis with X-linked myotubular myopathy. Peliosis hepatis is characterized by multiple blood-filled cavities of various sizes in the liver, which occurs in chronic wasting disease or with the use of specific drugs. X-linked myotubular myopathy is one of the most serious types of congenital myopathies, in which an affected male infant typically presents with severe hypotonia and respiratory distress immediately after birth. Although each disorder is rare, 12 cases of pediatric peliosis hepatis associated with X-linked myotubular myopathy have been reported, including our case. Peliosis hepatis should be considered as a cause of hepatic hemorrhage despite its low incidence, and it requires adequate gross and histological investigation for correct diagnosis., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Impaired hepatic glucose uptake (HGU) causes postprandial hyperglycemia in type 2 diabetes. Here, we show that diminished hepatic Sirt2 activity impairs HGU in obese diabetic mice. Hepatic Sirt2 overexpression increases HGU in high-fat diet (HFD)-fed obese diabetic mice and mitigates their impaired glucose tolerance. Hepatic Sirt2 knockdown in non-diabetic mice reduces HGU and causes impaired glucose tolerance. Sirt2 promotes glucose-dependent HGU by deacetylating K126 of glucokinase regulatory protein (GKRP). Glucokinase and GKRP glucose-dependent dissociation is necessary for HGU but is inhibited in hepatocytes derived from obese diabetic mice, depleted of Sirt2 or transfected with GKRP acetylation-mimicking mutants. GKRP deacetylation-mimicking mutants dissociate from glucokinase in a glucose concentration-dependent manner in obese diabetic mouse-derived hepatocytes and increase HGU and glucose tolerance in HFD-induced or db/db obese diabetic mice. We demonstrate that Sirt2-dependent GKRP deacetylation improves impaired HGU and suggest that it may be a therapeutic target for type 2 diabetes.

Carbon monoxide (CO) has attracted attention as a possible therapeutic agent for affecting anti-inflammatory and antioxidant activities. Previously, CO-bound hemoglobin vesicle (CO-HbV) was developed as a nanotechnology-based CO donor, and its safety profile and therapeutic potential as a clinically applicable carrier of CO were examined in vitro and in vivo. In the present study, the therapeutic efficacy of CO-HbV against severe acute pancreatitis was examined with secondary distal organ-injured model mice that were fed with a choline-deficient ethionine-supplemented diet. A CO-HbV treatment significantly reduced the mortality of the acute pancreatitis model mice compared to saline and HbV. Biochemical and histological evaluations clearly showed that CO-HbV suppressed acute pancreatitis by inhibiting the production of systemic proinflammatory cytokines, neutrophil infiltration, and oxidative injuries in pancreatic tissue. Interestingly, CO-HbV also diminished the subsequent damage to distal organs including liver, kidneys, and lungs. This could be due to the suppression of neutrophil infiltration into tissues and the subsequently enhanced oxidative injuries. In contrast, O 2 -bound HbV, the inactive form of CO-HbV, was ineffective against both pancreatitis and distal organ injuries, confirming that CO was directly responsible for the protective effects of CO-HbV in acute pancreatitis. These findings suggest that CO-HbV has anti-inflammatory and antioxidant characteristics of CO and consequently exerts a superior protective effect against acute pancreatitis-induced multiorgan damage., Competing Interests: Hiromi Sakai holds patents related to the production and utilization of Hb vesicles. The other authors report no conflicts of interest in this work.

Central insulin action activates hepatic IL-6/STAT3 signaling, which suppresses the gene expression of hepatic gluconeogenic enzymes. The vagus nerve plays an important role in this centrally mediated hepatic response; however, the precise mechanism underlying this brain-liver interaction is unclear. Here, we present our findings that the vagus nerve suppresses hepatic IL-6/STAT3 signaling via α7-nicotinic acetylcholine receptors (α7-nAchR) on Kupffer cells, and that central insulin action activates hepatic IL-6/STAT3 signaling by suppressing vagal activity. Indeed, central insulin-mediated hepatic IL-6/STAT3 activation and gluconeogenic gene suppression were impeded in mice with hepatic vagotomy, pharmacological cholinergic blockade, or α7-nAchR deficiency. In high-fat diet-induced obese and insulin-resistant mice, control of the vagus nerve by central insulin action was disturbed, inducing a persistent increase of inflammatory cytokines. These findings suggest that dysregulation of the α7-nAchR-mediated control of Kupffer cells by central insulin action may affect the pathogenesis of chronic hepatic inflammation in obesity., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Red blood cell (RBC) transfusions for controlling hemorrhaging induce systemic ischemia reperfusion, resulting in a decrease in hepatic cytochrome P450 (CYP) levels. Carbon monoxide (CO), when bound to red blood cells (CO-RBC) has the potential to protect the hepatic CYP protein to produce a resuscitative effect in a hemorrhagic shock rat model. The aim of this study was to investigate the mechanism by which CO-RBC resuscitation from a massive hemorrhage protects against a decrease in hepatic CYP. In the early phase (∼1h) after a hemorrhage and RBC resuscitation, hepatic CYP protein levels were significantly decreased with increasing hepatic free heme levels, but were maintained by a pre-treatment of gadolinium chloride (GdCl3), a Kupffer cell inhibitor, and Trolox, an anti-oxidant agent, as well as CO-RBC resuscitation. Under these conditions, the production of reactive oxygen species (ROS) derived from activated Kupffer cells was increased, but this increase was suppressed by CO-RBC resuscitation. At a late phase (6∼24h), CYP mRNA levels decreased after hemorrhage and RBC resuscitation, but not in the case of CO-RBC resuscitation. The increases in plasma IL-6 and TNF-α levels were decreased by CO-RBC resuscitation via the suppression of the toll-like receptor-4 (TLR-4) and the expression of the high mobility group box-1 (HMGB-1). Hepatic CYP protection after a hemorrhage and CO-RBC resuscitation can be attributed to the inactivation of Kupffer cells, resulting in the suppression of ROS production in the early phase and the suppression of inflammatory cytokine production via the TLR-4/HMGB-1signal pathway in the late phase., (Copyright © 2015 Elsevier Inc. All rights reserved.)

In 1998, a 68-year-old woman was diagnosed with rheumatoid arthritis. She was treated with prednisolone, nonsteroidal anti-inflammatory drugs, methotrexate (MTX), and biological drugs. Retroperitoneal lymph node swelling and hepatosplenomegaly appeared but spontaneously disappeared after drug withdrawal. Anorexia and general fatigue occurred in March 2012. She was admitted to our hospital with retroperitoneal, periaortic, and mediastinal lymph node swelling and was found to have multiple liver tumors. Based on the results of aspiration biopsy of a liver tumor, she was diagnosed with malignant lymphoma (Hodgkin lymphoma). She died from liver failure and disseminated intravascular coagulation before chemotherapy. We present this case of MTX-associated lymphoproliferative disorder, which caused formation of a liver tumor.

A 67-year-old man presented with a crossbow injury sustained in a suicide attempt during which he fixed the crossbow to a table. Although he retired to bed without treatment on the day of the initial injury, his pain increased the following day, and he was admitted to our hospital. On arrival, his vital signs were stable and a 10-mm diameter crossbow arrow that had penetrated the right anterior chest remained in place. Chest computed tomography revealed suspected damage to the right middle lobe, diaphragm, and liver. A right anterior thoracotomy was performed with partial resection of the middle lobe, diaphragm repair, and arrest of hepatic bleeding. There were no complications, and his postoperative course was uneventful. On day 12 after surgery, he was transferred to the psychiatry department of another hospital for treatment of his depression.

Red blood cell (RBC) transfusions are the gold standard in cases of massive hemorrhage, but induce hepatic ischemia-reperfusion injury, a serious complication associated with hemorrhage and RBC resuscitation. Thus, the development of a novel resuscitable fluid that is not associated with hepatic ischemia-reperfusion injury would be desirable. It was reported that exogenous carbon monoxide (CO) treatment ameliorated hepatic ischemia-reperfusion injury accompanying liver transplantation. This suggests that transfusions with CO-bound RBC (CO-RBC) might protect against hepatic ischemia-reperfusion injury following massive hemorrhage and resuscitation compared with RBC resuscitation. To investigate this, we created a hemorrhagic shock model rat, followed by resuscitation with RBC and CO-RBC. Hepatic ischemia-reperfusion injury and the destruction of hepatic cytochrome P450 (CYP) were significantly ameliorated in the CO-RBC resuscitation group compared with the RBC resuscitation group. The free heme derived from the destruction of hepatic CYP was correlated with hepatic oxidation and injury, suggesting that CO-RBC was a major factor in the amelioration of hepatic ischemia-reperfusion injury induced by hemorrhage and resuscitation via hepatic CYP protection. These results indicate that CO-RBC has potential for use as a resuscitative fluid in blood transfusion and does not suffer from the limitations associated with the RBC transfusions that are currently in use., (© 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.)

We have previously reported that epiregulin is a growth factor that seems to act on liver progenitor cells (LPCs) during liver regeneration. However, the relationship between epiregulin and LPCs has remained unclear. The aim of the present study was to clarify the role of epiregulin during liver regeneration. The serum levels of epiregulin in patients with acute liver failure were examined. A liver injury model was developed using mice fed a diet containing 0.1% 3.5-diethoxycarbonyl-1.4-dihydrocollidine (DDC) to induce LPCs. We then evaluated the expression of epiregulin and LPCs in these mice. The proliferation of epithelial cell adhesion molecule + LPCs cultured with epiregulin was examined in vitro, and finally epiregulin was overexpressed in mouse liver. In patients with acute liver failure, serum epiregulin levels were elevated significantly. In DDC mice, LPCs emerged around the portal area. Epiregulin was also detected around the portal area during the course of DDC-induced liver injury and was partially coexpressed with Thy1. Serum epiregulin levels in DDC mice were also significantly elevated. Recombinant epiregulin augmented the proliferative capacity of the LPCs in a dose-dependent manner. In mice showing overexpression of epiregulin, the expression of PCNA on hepatocytes was increased significantly. Finally, LPCs emerged around the portal area after epiregulin gene delivery. We concluded that epiregulin promotes the proliferation of LPCs and DNA synthesis by hepatocytes and is upregulated in the serum of patients with liver injury. Furthermore, induction of epiregulin leads to the appearance of LPCs. Epiregulin would be a useful biomarker of liver regeneration., (Copyright © 2014 the American Physiological Society.)

Human embryonic stem cells (hESCs) could provide a major window into human developmental biology, because the differentiation methods from hESCs mimic human embryogenesis. We previously reported that the overexpression of hematopoietically expressed homeobox (HHEX) in the hESC-derived definitive endoderm (DE) cells markedly promotes hepatic specification. However, it remains unclear how HHEX functions in this process. To reveal the molecular mechanisms of hepatic specification by HHEX, we tried to identify the genes directly targeted by HHEX. We found that HHEX knockdown considerably enhanced the expression level of eomesodermin (EOMES). In addition, HHEX bound to the HHEX response element located in the first intron of EOMES. Loss-of-function assays of EOMES showed that the gene expression levels of hepatoblast markers were significantly upregulated, suggesting that EOMES has a negative role in hepatic specification from the DE cells. Furthermore, EOMES exerts its effects downstream of HHEX in hepatic specification from the DE cells. In conclusion, the present results suggest that HHEX promotes hepatic specification by repressing EOMES expression.

Purpose: Modeling the postmortem liver for autopsy imaging is a challenging problem owing to the variation in organ deformation found in cadavers and limited availability of postmortem liver CT scans. An algorithm was developed to construct a statistical shape model (SSM) for the adult postmortem liver in autopsy imaging., Methods: First, we investigated the relationship between SSMs obtained from in vivo liver CT scans and those from postmortem cases. Liver shapes were embedded in level set functions and statistically modeled using a spatially weighted principal components analysis. The performance of the SSMs was evaluated in terms of generalization and specificity. Several algorithms for the transformation from in vivo livers to postmortem livers were proposed to enhance the performance of an SSM for a postmortem liver, followed by a comparative study on SSMs. Specifically, five SSMs for a postmortem liver were constructed and evaluated using 32 postmortem liver labels, and postmortem liver labels synthesized from 144 in vivo liver labels were constructed using the proposed transformation algorithms. We also compared the proposed SSMs with three conventional SSMs trained from postmortem liver labels and/or in vivo liver labels., Results: The investigation showed that the performance of an SSM constructed using in vivo liver labels suffered when describing postmortem liver shapes. Two of the five proposed SSMs trained using synthesized postmortem livers showed the best performance with no significant differences between them, and they statistically outperformed all conventional SSMs tested., Conclusions: The performance of conventional SSMs can be improved by using both postmortem liver shape labels and artificial shape labels synthesized from in vivo liver shape labels.

Although growing evidence suggests a major role for T cells in the pathogenesis of primary biliary cirrhosis (PBC), the roles of natural killer (NK) and natural killer T (NKT) cells, which predominate in the liver, in the pathogenesis of PBC remain unclear. We investigated the status of NK and NKT cells in the liver and peripheral blood samples obtained from 11 patients with asymptomatic PBC diagnosed as stage I or II (early PBC) and 7 patients with symptomatic PBC who underwent liver transplantation (advanced PBC) using flow cytometry and immunohistochemical staining. The proportions of NK and NKT cells were significantly decreased in the liver of patients with early PBC compared with normal donors. However, the proportion of CD56+ NKT cells was increased in the liver of patients with advanced PBC. Moreover, the proportion of activated Fas ligand (FasL)-positive NKT cells was significantly increased in the liver of patients with advanced PBC compared with early PBC (P=0.013). We also found increased expression of FasL on lymphocytes infiltrating around the injured bile duct in advanced PBC using immunohistochemical staining. Our results suggest that activated NKT cells may contribute to the biliary epithelial cell death resulting in the progression of PBC.

Recently, the range of applications of surgical staplers has been extended to include laparoscopic liver resection because manipulation of a surgical stapler is very simple. Revealing the causes of stapling failure and suggesting a method to solve stapling failure are important for safe laparoscopic liver resection. Surgeons say that tissues make stapling more likely to fail if they are thick and brittle. However, the combinatorial effect of the thickness and stiffness of tissues on the success of surgical stapling for laparoscopic liver resection has not been investigated. Therefore, the objective of the present study was to investigate the effect of tissue thickness and tissue stiffness on the success rate (SR) of surgical stapling. From ex vivo stapling experimental results using pig livers, it is suggested that the effect of tissue thickness is greater than the effect of tissue stiffness on the SR of stapling. If tissue thickness is 5 mm, the SR of stapling is high regardless of the magnitude of the tissue-stiffness parameter. However, if tissue thickness is >10 mm, the SR of stapling has a relationship with nonlinear viscoelastic parameters. Therefore, the SR of stapling could be predicted from tissue thickness and nonlinear elastic parameters.

Glucose intolerance in type 2 diabetes is related to enhanced hepatic glucose production (HGP) due to the increased expression of hepatic gluconeogenic enzymes. Previously, we revealed that hepatic STAT3 decreases the expression of hepatic gluconeogenic enzymes and suppresses HGP. Here, we show that increased plasma histidine results in hepatic STAT3 activation. Intravenous and intracerebroventricular (ICV) administration of histidine-activated hepatic STAT3 reduced G6Pase protein and mRNA levels and augmented HGP suppression by insulin. This suppression of hepatic gluconeogenesis by histidine was abolished by hepatic STAT3 deficiency or hepatic Kupffer cell depletion. Inhibition of HGP by histidine was also blocked by ICV administration of a histamine H1 receptor antagonist. Therefore, histidine activates hepatic STAT3 and suppresses HGP via central histamine action. Hepatic STAT3 phosphorylation after histidine ICV administration was attenuated in histamine H1 receptor knockout (Hrh1KO) mice but not in neuron-specific insulin receptor knockout (NIRKO) mice. Conversely, hepatic STAT3 phosphorylation after insulin ICV administration was attenuated in NIRKO but not in Hrh1KO mice. These findings suggest that central histidine action is independent of central insulin action, while both have additive effects on HGP suppression. Our results indicate that central histidine/histamine-mediated suppression of HGP is a potential target for the treatment of type 2 diabetes.

Radio frequency ablation (RFA) is usually conducted using ultrasound (US) imaging to monitor the insertion procedure and the coagulation extent of liver tissue which is contiguous to the RFA electrode. However, when RFA surgery is started, the US image becomes unclear because of water vapor. This disadvantage of RFA can lead to excessive and insufficient RFA thereby diminishing the advantages of the procedure. In the present study, we proposed a simulation system which shows the progress status of coagulation for liver RFA. To derive the coagulation characteristics in liver RFA, we used the viscoelasticity of liver tissue as the coagulation indicator to investigate coagulation development for liver RFA. This paper shows the acquisition procedures for analyzing the relationship between the rate of temperature and viscoelasticity. We measured the complex modulus of porcine liver tissue under different rate of temperature in RFA by controlling the output power. We showed that the viscoelasticity of liver tissue depended on temperature previous temperature increase above 60°C. This result indicates that in RFA, controlling the output power is important to completely coagulate the tumor.

Red blood cell (RBC) transfusions for massive hemorrhage induce systemic ischemic-reperfusion and influence the disposition and pharmacological activity of drugs as a result of a reduction in the level of expression and activity of cytochrome P450s (P450). It was reported that, when organ-preserving solutions are exposed to carbon monoxide (CO), the treatment was effective in suppressing the postreperfusion reduction in renal P450 levels in cases of kidney transplantation. Therefore, we hypothesized that transfusions with RBC that contain bound CO (CO-RBC) would protect the hepatic level of rat P450 during a massive hemorrhage, compared with plasma expanders and RBC resuscitation. To achieve this, we created 40% hemorrhagic-shock model rats, followed by resuscitation, with use of recombinant human serum albumin, RBCs, and CO-RBCs. At 1 hour after resuscitation, the expressions of hepatic P450 isoforms (1A2, 2C11, 2E1, and 3A2) were significantly decreased in the RBC resuscitation group, compared with the sham group. Such alterations in hepatic P450 significantly resulted in an increase in the plasma concentrations of substrate drugs (caffeine [1A2], tolbutamide [2C11], chlorzoxazone [2E1], and midazolam [3A2]) for each P450 isoform, and thus, the hypnotic action of midazolam could be significantly prolonged. Of interest, the reductions in hepatic P450 activity observed in the RBC group were significantly suppressed by CO-RBC resuscitation, and consequently, the pharmacokinetics of substrate drugs and the pharmacological action of midazolam remained at levels similar to those under sham conditions. These results indicate that CO-RBC resuscitation has considerable potential in terms of achieving safe and useful drug therapy during massive hemorrhages.

Purpose: To develop and evaluate a quantitative parameter for staging hepatic fibrosis by contrast enhancement signal intensity and morphological measurements from gadoxetic acid (Gd-EOB-DTPA)-enhanced MR imaging., Materials and Methods: MR images were obtained in 93 patients; 75 patients had histopathologically proven hepatic fibrosis and 18 patients who had healthy livers were evaluated. The liver-to-muscle signal intensity ratio (SI(post) = SIliver/SImuscle), contrast enhancement index (CEI = SIpost/SIpre), and liver-to-spleen volumetric ratio (VR = Vliver/Vspleen) were evaluated for staging hepatic fibrosis., Results: VR was most strongly correlated with fibrosis stage (7.21; r = -0.83; P < 0.001). Sensitivity, specificity, and area under the ROC curve demonstrated by linear regression formula generated by VR and CEI in predicting fibrous scores were 100%, 73%, and 0.91, respectively, for the detection of hepatic fibrosis F1 or greater (≥ F1),100%, 87%, and 0.96 for ≥ F2, 74%, 98%, and 0.93 for ≥ F3 and 91%, 100%, and 0.97 for F4., Conclusion: The liver-to-spleen volumetric ratio and contrast enhancement index were reliable biomarkers for the staging of hepatic fibrosis on Gd-EOB-DTPA-enhanced MR imaging., (Copyright © 2012 Wiley Periodicals, Inc.)

Human α(1) -acid glycoprotein (AGP), a lipocalin family member, serves as a carrier for basic drugs and endogenous hormones. It is mainly distributed in the liver and also has anti-inflammatory effects. We previously discovered a protein in liver parenchymal cells that interacts with AGP and it was identified as hemoglobin β-chain (HBB). The purpose of this study was to clarify the role of HBB in the hepatic cellular uptake of AGP. Ligand blotting experiments showed that the interaction of (125) I-AGP with hemoglobin was saturable and was significantly suppressed in the presence of excess unlabeled AGP. In addition, the cellular uptake of fluorescein isothiocianate-AGP by HepG2 cells was saturable and temperature dependent. This uptake was inhibited by fillipin and methyl-β-cyclodextrin, but not chlorpromazine, suggesting that AGP is taken up via caveolae/lipid rafts endocytic pathway. Immunostaining showed that HBB and caveolin-1, exclusively expressed in caveolae, were partially colocalized on the plasma membranes of HepG2 cells. HBB knockdown with siRNA decreased the uptake of AGP by HepG2 cells by 40%, and exogenous hemoglobin inhibited the uptake by 40%-50%. These findings indicate that HBB is located on the liver plasma membrane and that it contributes to the intracellular uptake of AGP., (Copyright © 2012 Wiley Periodicals, Inc.)

Human α(1) -acid glycoprotein (AGP), a serum glycoprotein, is known to have anti-inflammatory activity. We recently reported that AGP was mainly incorporated into the liver in mice via a receptor-mediated pathway, although the mechanism for this was largely unknown. The objective of this study was to identify the specific cellular surface protein that recognizes the peptide moiety of AGP. Pharmacokinetic studies of (111) In-AGP and (111) In -recombinant glycan-deficient AGP (rAGP) in mice demonstrated that both AGPs are mainly distributed to the liver and kidney, but hepatic and renal uptake clearance of rAGP was higher than that for AGP. Hepatic uptake of rAGP was inhibited in the presence of 100-fold excess of unlabeled AGP, indicating that the hepatic uptake of rAGP shared a common route with that of AGP and that it recognized the peptide moiety of AGPs. In ligand blotting analyses using crude cellular membrane fraction of mice liver, a band corresponding to a 16 kDa protein was observed to bind to both AGPs. Interestingly, matrix-assisted laser desorption ionization-time-of-flight mass spectrometry MALDI-TOF-MS and western blotting analyses indicated that this 16 kDa protein is the hemoglobin β-chain (HBB). It, therefore, appears that HBB is associated with the hepatic uptake of AGP via a direct interaction with its peptide moiety., (Copyright © 2011 Wiley Periodicals, Inc., A Wiley Company.)

In the liver, signal transducer and activator of transcription 3 (STAT3) plays an important role in the suppression of gluconeogenic enzyme expression. While obesity-associated endoplasmic reticulum (ER) stress has been shown to increase hepatic gluconeogenic enzyme expression, the role of ER stress in STAT3-dependent regulation of such expression is unclear. The current study aimed to elucidate the effect of ER stress on the STAT3-dependent regulation of hepatic gluconeogenic enzyme expression. Genetically obese/diabetic db/db mice and db/db mouse-derived isolated hepatocytes were used as ER stress models. A tyrosine phosphatase inhibitor, a deacetylation inhibitor, and an acetylated mutant of STAT3 were used to examine the effect of ER stress on hepatic STAT3 action. ER stress inhibited STAT3-dependent suppression of gluconeogenic enzyme gene expression by suppressing hepatic Janus kinase (JAK)2 and STAT3 phosphorylation. A tyrosine phosphatase inhibitor restored ER stress-induced suppression of JAK2 phosphorylation but exhibited no improving effect on suppressed STAT3 phosphorylation. STAT3 acetylation is known to correlate with its phosphorylation. ER stress also decreased STAT3 acetylation. An acetylated mutant of STAT3 was resistant to ER stress-induced inhibition of STAT3-phosphorylation and STAT3-dependent suppression of hepatic gluconeogenic enzyme gene expression in vitro and in vivo. Trichostatin A, a histone deacetylase (HDAC) inhibitor, ameliorated ER stress-induced inhibition of STAT3 acetylation and phosphorylation. The current study revealed that ER stress inhibits STAT3-dependent suppression of hepatic gluconeogenic enzymes via JAK2 dephosphorylation and HDAC-dependent STAT3 deacetylation, playing an important role in the increase of hepatic glucose production in obesity and diabetes.

Radiofrequency (RF) ablation is increasingly used to treat cancer because it is minimally invasive. However, it is difficult for operators to control precisely the formation of coagulation zones because of the inadequacies of imaging modalities. To overcome this limitation, we previously proposed a model-based robotic ablation system that can create the required size and shape of coagulation zone based on the dimensions of the tumor. At the heart of such a robotic system is a precise temperature distribution simulator for RF ablation. In this article, we evaluated the simulation accuracy of two numerical simulation liver models, one using a constant thermal conductivity value and the other using temperature-dependent thermal conductivity values, compared with temperatures obtained using in vitro experiments. The liver model that reflected the temperature dependence of thermal conductivity did not result in a large increase of simulation accuracy compared with the temperature-independent model in the temperature range achieved during clinical RF ablation.

Recently radiofrequency (RF) ablation has become increasingly important in treating liver cancers. RF ablation is ordinarily conducted using elastographic imaging to monitor the ablation procedure and the temperature of the electrode needle is displayed on the RF generator. However, the coagulation boundary of liver tissue in RF ablation is unclear and unconfident. This can lead to both excessive and insufficient RF ablation thereby diminishing the advantages of the procedure. In the present study, we developed a method for determining the coagulation boundary of liver tissue in RF ablation. To investigate this boundary we used the mechanical characteristics of biochemical components as an indicator of coagulation to produce a relational model for viscoelasticity and temperature. This paper presents the data acquisition procedures for the viscoelasticity characteristics and the analytical method used for the coagulation model. We employed a rheometer to measure the viscoelastic characteristics of liver tissue. To determine the model functional relationship between viscoelasticity and temperature, we used a least-square method and the minimum root mean square error was calculated to optimize the model functional relations. The functional relation between temperature and viscoelasticity was linear and non-linear in different temperature regions. The boundary between linear and non-linear functional relation was 58.0°C.

Diffusion-weighted (DWI) magnetic resonance (MR) imaging is useful in diagnosing various pathologic conditions in the liver, such as malignant tumors or hepatic fibrosis, and is now part of routine MR imaging protocols for the liver following the development of a parallel encoding technique that has markedly improved image quality. DWI is not very sensitive for detecting hepatocellular carcinomas (HCC) and is useless for characterizing border-line hepatocellular nodules in cirrhosis, but it complements gadolinium-enhanced MR imaging in detecting regional tumor recurrence or intrahepatic metastases of HCC following treatment. DWI is more useful for detecting hepatic metastasis, because histopathologic architecture of metastases does not resemble that of liver tissue and T(2) relaxation time of hepatic metasitasis is fairly longer than that of liver parenchyma. DWI is also useful for detecting moderate and advanced hepatic fibrosis. In cirrhosis, however, decreased blood flow in fibrotic liver is thought to lower apparent diffusion coefficient of the liver. For MR perfusion analysis, a dual-input one-compartment model is used to correlate various hepatic blood flow parameters that represent hepatic arterial/portal blood flow or fraction, mean transit time, and distribution volume with the severity of cirrhosis and portal hypertension. Conventional multisectional imaging and perfusion study can be combined using a 3-dimensional sequence with high temporal resolution, but spatial resolution is not sufficiently high to diagnose tiny hepatic lesions. The advent of liver-specific contrast agents, such as gadoxetic acid, may spur the development of a new analysis model that incorporates extracellular perfusion and hepatocyte function.

Purpose: To determine the optimal iodine dose for aortic and hepatic enhancement at MDCT by comparing lean body weight (LBW) with total body weight (TBW)., Materials and Methods: This study was approved by our institutional review committee. One hundred and thirty-six patients were randomized into four groups: 550, 650, 750 mg iodine/(kg of LBW) and 600 mgI/(kg of TBW). The aortic and hepatic contrast enhancements (Δ HUs) during the portal venous-phase and variances of ΔHUs were compared., Results: Mean ΔHUs for 550, 650, 750 mgI/kg LBW and 600 mgI/kg TBW were: 95.1, 109.9, 122.4, and 131.2HU, respectively, for the aorta. For the liver, 43.1, 55.4, 60.8, and 63.5 HU. Mean Δ HUs increased with iodine dose per kg LBW (p<0.01), but no significant difference between 750 mgI/kg LBW and 600 mgI/kg TBW groups. Hepatic enhancement increased by ≥50 HU in 94% of patients with 750 mg/kg LBW. Variance of hepatic enhancement was marginally greater in the 600 mgI/kg TBW than in the 550 and 750 mgI/kg LBW., Conclusion: Hepatic enhancement variation was reduced with iodine doses based on LBW. Iodine dose of 750 mg iodine/kg LBW was appropriate to achieve hepatic enhancement≥50 HU in 94% of patients., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Unlabelled: In FDG-PET for abdominal malignancy, the liver may be assumed as an internal standard for grading abnormal FDG uptake both in early images and in delayed images. However, physiological variables of FDG uptake by the liver, especially the effects of blood glucose level, have not yet been elucidated., Methods: FDG-PET studies of 70 patients examined at 50 to 70 min after injection (60 ± 10 min: early images) and of 68 patients examined at 80 to 100 min after injection (90 ± 10 min: delayed images) were analyzed for liver FDG uptake. Patients having lesions in the liver, spleen and pancreas; patients having bulk tumor in other areas; and patients early after chemotherapy or radiotherapy were excluded; also, patients with blood glucose level over 125 mg/dl were excluded., Results: Mean standardized uptake value (SUV) of the liver, blood glucose level and sex showed no significant differences between early images and delayed images. However, liver SUV in the delayed image showed a larger variation than that in the early image and showed significant correlation to blood glucose level. The partial correlation coefficient between liver SUV and blood glucose level in the delayed image with adjustment for sex and age was 0.73 (P < .0001). Multivariate regression coefficient (95% confidence interval) of blood glucose was 0.017 (0.013-0.021)., Conclusion: Blood glucose level is an important factor affecting the normal liver FDG uptake in nondiabetic patients. In the case of higher glucose level, liver FDG uptake is elevated especially in the delayed image. This may be due to the fact that the liver is the key organ responsible for glucose metabolism through gluconeogenesis and glycogen storage., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Radiofrequency ablation is increasingly being used for liver cancer because it is a minimally invasive treatment method. However, it is difficult for the operators to precisely control the formation of coagulation zones because of the cooling effect of capillary vessels. To overcome this limitation, we have proposed a model-based robotic ablation system using a real-time numerical simulation to analyze temperature distributions in the target organ. This robot can determine the adequate amount of electric power supplied to the organ based on real-time temperature information reflecting the cooling effect provided by the simulator. The objective of this study was to develop a method to estimate the intraoperative rate of blood flow in the target organ to determine temperature distribution. In this paper, we propose a simulation-based method to estimate the rate of blood flow. We also performed an in vitro study to validate the proposed method by estimating the rate of blood flow in a hog liver. The experimental results revealed that the proposed method can be used to estimate the rate of blood flow in an organ.

Human serum albumin (HSA), a non-glycosylated protein, is widely employed as carrier for drug delivery systems. A series of recombinant, mannosylated-HSA mutants (Man-rHSAs: D63N, A320T and D494N) and their triple mutant (TM-rHSA: D63N/A320T/D494N) were prepared, that can be selectively delivered to the liver via mannose receptor (MR) on the liver non-parenchymal cells. A pharmacokinetic analysis of (111)In-Man-rHSAs in mice showed that they were rapidly cleared from the blood circulation, and were largely taken up by the liver rapidly in the order: TM-rHSA>D494N>>A320T=D63N, consistent with their degree of mannosylation. In vivo competition experiments with an excess amount of chemically modified Man-BSA or mannan suggested that the hepatic uptake of TM-rHSA was selectively mediated by MR on Kupffer cells. Lastly, a TM-rHSA-NO conjugate, S-nitrosylated TM-rHSA, effectively delivered NO to the liver and then exhibited a significant inhibitory effect against hepatic ischemia/reperfusion injury model rats, accompanied by the induction of heme oxygenase-1., (2010. Published by Elsevier B.V. All rights reserved.)

Objective: The purpose of our work was to develop an integrated system with image guidance and deformation simulation for the purpose of accurate needle insertion., Methods: We designed an ultrasound-guided needle insertion manipulator and physical model to simulate liver deformation. We carried out an in vivo experiment using a porcine liver to verify the effectiveness of our manipulator and model., Results: The results of the in vivo experiment showed that the needle insertion manipulator accurately positions the needle tip into the target. The experimental results also showed that the liver model accurately reproduces the nonlinear increase of force upon the needle during insertion., Discussion: Based on these results, it is suggested that the needle insertion manipulator and the physical liver model developed and validated in this work are effective for accurate needle insertion., (Copyright 2009 Elsevier Ltd. All rights reserved.)

Human alpha(1)-acid glycoprotein (AGP), a serum glycoprotein, is thought to have anti-inflammatory effects by a mechanism that is not well understood. In this study, we investigated the pharmacokinetics of AGP in mice using enzymatically modified AGP (AGP with the sialic acids removed, asialo-AGP, and with both sialic acids and galactose removed, agalacto-AGP). It was observed that AGP was eliminated from the circulation slowly, and was mainly taken up by the liver. The elimination of labeled AGP, asialo-AGP and agalacto-AGP from the circulation was suppressed in the presence of excess unlabeled AGP, asialo-AGP and agalacto-AGP, respectively, suggesting the receptor-mediated uptake of these AGPs. Interestingly, the uptake of AGP by the liver competed with agalacto-AGP, but not with asialo-AGP, while agalacto-AGP competed with asialo-AGP. These results suggest that agalacto-AGP binds to at least two types of receptors, namely asialoglycoprotein receptor (ASGPR) and an as yet unidentified receptor that is shared with AGP, and that AGP is directly taken up by the liver through such a receptor and not via ASGPR. These findings help improve our understanding of the clearance mechanism of AGP.

Radiofrequency ablation (RFA) for liver cancer has increasingly been used over the past few years because RFA is minimally invasive treatment for patients. However, precise control of the formation of coagulation zones is difficult for operators due to inadequate imaging modalities. With this in mind, we have proposed a model-based robotic ablation system using numerical simulation to analyze temperature distributions in the organ to overcome this deficiency. The objective of our work is to develop a temperature-dependent thermophysical organ model to construct a precise numerical simulator for RFA. However, no standard methods exist for obtaining the thermophysical properties of biological tissues, as detailed evaluations of the accuracy of properties obtained from various experiments have not been completed. The purpose of this study was thus to measure and model the temperature dependence of thermal conductivity in hog liver from three representative methods, and to compare these results using our developed numerical simulator to reveal differences in temperature distributions stemming from differences in thermal conductivities.

The elongation of poly(A) tails in cytoplasm is essential for oogenesis and early embryogenesis in Xenopus laevis. mGLD-2 is a mouse homologue of Xenopus cytoplasmic poly(A) polymerase xGLD-2. We found an association of mGLD-2 with cytoplasmic polyadenylation components, CPEB and CPSF described in Xenopus oocytes. To clarify the role of mGLD-2 in mouse, we produced an mGLD-2 disrupted mouse line by homologous recombination. In spite of the ubiquitous expression of mGLD-2, the disrupted mice were apparently normal and healthy. Moreover, it was demonstrated that mGLD-2 disruption did not affect the poly(A) tail elongation in oocytes using reporter RNAs. Coincide with these observations, the maturation of the oocytes was normal and the mice were fertile. Thus mGLD-2 is dispensable for full-term development and oogenesis. Our results also indicate that there is another source of cytoplasmic poly(A) polymerase in mouse.

While organ-specific stem cells with roles in tissue injury repair have been documented, their pathogenic significance in diseases and the factors potentially responsible for their activation remain largely unclear. In the present study, heart, kidney, brain, and skin samples from F344 transgenic rats carrying the GFP gene were transplanted into normal F344 rat liver one day after an intraperitoneal injection (i.p.) of carbon tetrachloride (CCl(4)) to test their differentiation capacity. The transplantation was carried out by female donors to male recipients, and vice versa. One week after transplantation, GFP antigen-positive cells with phenotypic characteristics of hepatocytes were noted. After two weeks, their extent increased, and at 4 weeks, large areas of strongly GFP-stained cells developed. All recipient livers had GFP antigen-positive hepatocyte cells. PCR analysis coupled with laser capture micro-dissection (LCM) revealed those cells to contain GFP DNA. Thus, our results indicate that tissue stem cells have multipotential ability, differentiating into hepatocytes when transplanted into an injured liver.

DBA/2 (H-2(d)) mice are known to be more resistant than C57BL/6 (B6, H-2(b)) mice to the non-lethal 17XNL strain of Plasmodium yoelii. This is a very strange phenomenon because the functions of conventional T cells, especially CD8(+) T cells, are known to be somewhat lower in DBA/2 mice than in other strains of mice. We examined herein how immune responses differed between DBA/2 mice and B6 mice during malarial infection. DBA/2 mice and (DBA/2 x B6)F(1) (BDF(1), H-2(b/d)) mice were found to have milder parasitaemia and to recover more quickly from malarial infection than B6 mice. These DBA/2 and BDF(1) mice were also found to experience a marked expansion of interleukin (IL)-2Rbeta(+) CD3(int) cells and gammadelta T cells in the liver, especially in the recovery phase. The expansion of unconventional T cells (i.e. B220(+) T cells) was also marked in DBA/2 and BDF(1) mice. The majority of B220(+) T cells were gammadelta T cells and these T cells were double-negative CD4(-) CD8(-). More importantly, the production of immunoglobulin M (IgM)-type anti-DNA autoantibody was also higher in DBA/2 and BDF(1) mice than in B6 mice. In conjunction with data on cytokine production, these results indicate that primitive T and B cells, namely autoreactive extrathymic T cells and autoantibody-producing B cells, may be much more activated in DBA/2 mice and therefore resistant to the non-lethal 17XNL strain of P. yoelii.

We have previously reported that erythropoiesis commences in the liver and spleen after malarial infection, and that newly generated erythrocytes in the liver are essential for infection of malarial parasites as well as continuation of infection. At this time, erythropoietin (EPO) is elevated in the serum. In the present study, we administered EPO or anti-EPO antibody into C57BL/6 (B6) mice to modulate the serum level of EPO. When mice were infected with a non-lethal strain (17NXL) of Plasmodium yoelii (blood-stage infection of 10(4) parasitized erythrocytes per mouse), parasitemia continued for 1 month, showing a peak at day 17. Daily injection of EPO (200 IU/day per mouse) from day five to day 14 prolonged parasitemia, whereas injection of anti-EPO antibody (1.5 mg/day per mouse) every second day from day five to day 28 decreased it. Erythropoiesis was confirmed in the liver, spleen and bone marrow by the appearance of nucleated erythrocytes (TER119+). When anti-EPO antibody was injected by the same protocol into mice infected with a lethal strain (17XL) of P. yoelii, all mice showed decreased parasitemia and recovered from the infection. These results suggest that the use of anti-EPO antibody after malarial infection may be of therapeutic value in severe cases of malaria.

Carbon monoxide (CO) generated through the reaction of heme oxygenase (HO) has attracted great interest in regulation of hepatobiliary homeostasis. The gas generated by HO-2 in the hepatic parenchyma can modestly activate soluble guanylate cyclase (sGC) expressed in hepatic stellate cells in a paracrine manner and thereby constitutively relax sinusoids. Kupffer cells express HO-1, the inducible isozyme, even under normal unstimulated conditions and constitutes approximately 30% of the total HO activity in this organ. Upon exposure to a variety of stressors such as cytokines, endotoxin, hypoxia and oxidative stress, the liver induces HO-1 and over-produces CO. The stress-inducible CO has been shown to guarantee ample blood supply during detoxification of heme and thus to play a protective role in the liver. However, molecular mechanisms by which CO serves as a protectant for hepatocytes, the cells expressing little sGC, remain to be solved. Previous observation suggested that CO modulates intracellular calcium mobilization through inhibiting cytochrome P-450 activities and thereby maintain stroke volume of bile canalicular contraction in cultured hepatocytes. CO also stimulates mrp2-dependent excretion of bilirubin-IXalpha and helps heme catabolism. Although a direct molecular target responsible for the latter event remains unknown, such properties of CO could support xenobiotic metabolism through its actions on sinusoidal hemodynamics and hepatobiliary systems.

The human liver contains significant numbers of innate immune cells, such as natural killer (NK) cells and natural killer T (NKT) cells, which express both T-cell receptors and NK-cell receptors simultaneously. It has been suggested that the innate immune system plays a crucial role in the liver. In this report, the distribution of NK and NKT cells in the liver and peripheral blood of two patients with drug-induced fulminant hepatic failure (FHF) who had undergone living donor liver transplantation was examined. In both the liver and peripheral blood, the proportions of NK and NKT cells markedly decreased compared with those in healthy donors. It was also revealed that, unlike murine NKT cells, human CD56(+) T cells and CD57(+) T cells did not constitutively express CD28, which is one of the important costimulatory molecules on T cells. Additionally, the residual CD56(+) T cells and CD57(+) T cells in the patients expressed more CD28 than in controls. This result suggests that NKT cells might be more activated in FHF. Although the accumulation of further cases is required, it is suggested that both NK and NKT cells might be involved in hepatic injury in FHF.

Immunohistochemical assessment of 5-bromo-2-deoxyuridine (BrdU) in tissue sections is a widely used method to evaluate cell proliferation in vivo. However, this method requires time-consuming preparation of paraffin sections and laborious counting of BrdU-labeled nuclei on multiple sections. Here, we report the development of a rapid and reliable method to quantitate BrdU incorporation in intestinal and liver tissues using a dot-blot method. In vivo models of colon or liver proliferation were used to analyze the usefulness and reliability of this new method. Mice were killed after BrdU injection, and genomic DNA was isolated from the tissues, denatured, and dot-blotted onto a nitrocellulose membrane. The incorporated BrdU was detected with a BrdU monoclonal antibody, and the signal intensity was densitometrically quantified. Results were compared with BrdU index determined by conventional immunohistochemistry on the same tissue samples. The patterns of colonic BrdU incorporation during fasting and refeeding, measured by the dot-blotting method and the immunohistochemical method, were similar. The BrdU incorporation in the regenerating liver after partial hepatectomy, evaluated by these two different methods, showed a strong correlation (R(2) = 0.91, P < 0.01). In addition, the inhibition of colon proliferation by the phosphoinositol 3-kinase inhibitor wortmannin was demonstrated by this dot-blotting method. In conclusion, the dot-blotting technique described in this report provides an accurate, more efficient, and possibly more reliable method for the assessment of in vivo proliferation compared with conventional immunohistochemical determination of BrdU-labeling index.

A 70-year-old woman was admitted to our hospital because of a liver tumor. Laboratory data revealed mild liver dysfunction. Neither serum anti-HCV antibody nor HCV-RNA was detected. Computed tomography revealed a tumor lesion measuring 2 cm in diameter within the liver. Histological examination of the tumor revealed moderately differentiated hepatocellular carcinoma while the non-tumorous liver tissue demonstrated liver cirrhosis. By the RT-PCR method, HCV-RNA was detected from the non-tumorous liver tissue. We herein report a very rare case of hepatocellular carcinoma in a patient with liver cirrhosis associated with negative serum HCV findings, but positive finding for liver tissue HCV RNA.

Recently, T cells were classified into two categories: intrathymic T cells (ITCs; thymus-derived T cells) and extrathymic T cells (ETCs). ETC, localized in the liver and intestinal intraepithelium (IE), play an important immunologic role in the suppressed condition of T-cell development in the thymus. Given the fact that complications of surgery in patients with obstructive jaundice are often related to immunosuppression in the gut-liver circulation, we attempted to investigate the changes in the proportion of ETCs in mice with obstructive jaundice. Three mice models were prepared ( n = 10 per group): sham group with simple laparotomy; ligation group with common bile duct ligation; deoxycholic acid (DCA) group with an oral intake of DCA as a model of the presence of bile salts in the gut lumen. In each model, total mononuclear cells (MNCs), ITCs in the thymus, and ETCs in the liver and IE were counted using monoclonal antibodies in conjunction with a two-color immunofluorescence test by flow cytometry. In the ligation group the number of MNCs was reduced in the thymus and IE, and only those in the IE recovered after oral intake of DCA. A decrease of ITCs in the thymus and the increase in ETCs in the liver and IE occurred simultaneously during the early phase of biliary obstruction. At day 7 after biliary obstruction, ETCs in the livers of the DCA and ligation groups decreased to nearly the level in the sham group. However, on day 7 the ETCs in the IE remained significantly higher in the DCA group than in the ligation group. These results suggested that ETCs can act in place of ITCs at an early phase of obstructive jaundice, and the presence of bile in the gut lumen may be associated with the consumption of ETCs in the IE, a reaction that may bring about improved immunoreactivity.

The asialoglycoprotein receptor (ASGPR) is abundantly expressed on the sinusoidal surfaces of hepatocytes. We aimed to clarify the clinical significance of the regional distribution of ASGPRs in the human liver, especially in chronic viral hepatitis. Eighteen volunteers, 34 patients with chronic hepatitis, and 33 patients with cirrhosis (11/Child-Pugh A, 11/Child-Pugh B, 11/Child-Pugh C) were studied using a newly developed, conventional technetium-99m-diethylenetriaminepentaacetic acid-galactosyl human serum albumin ((99m)Tc-GSA), single photon emission computed tomography (SPECT) method. Using Cantlie's line as a guide, ASGPR dynamics were analyzed separately in the right and left lobes, as well as in the whole liver, using novel indices (the liver uptake ratio [LUR] and the liver uptake density [LUD], which reflect the amount and density of ASGPRs in the liver, respectively). Mean LUR and LUD values for the whole liver and the right and left lobes decreased with increasing progression of chronic viral hepatitis. The LUR for the whole liver correlated well with parameters measuring the hepatic functional reserve and the platelet count. The right LUR correlated particularly well with conventional liver function tests, and comparison of the right LUD with histologic findings showed that it was a good indicator of periportal and/or bridging necrosis and fibrosis. In conclusion, our (99m)Tc-GSA SPECT method was clinically useful in evaluating regional hepatic function and the progression of chronic viral hepatitis using dynamic changes in ASGPRs.

Plasmodium yoelii-infected erythrocytes were injected into mice with or without 6.5 Gy irradiation. This irradiation suppressed erythropoiesis and induced severe immunosuppression. However, these mice showed a rather delayed infection, suggesting that fresh erythrocytes may become malarial targets. In other words, malarial infection did not persist without newly generated erythrocytes in mice. We then examined erythropoiesis in the liver and bone marrow of mice with malaria. Surprisingly, erythropoiesis began in the liver. At this time, the serum level of erythropoietin (EPO) was prominently elevated and the EPO mRNA also became detectable in the kidney. Many clusters of red blood cells appeared de novo in the parenchymal space of the liver. These results revealed that malarial infection had a potential to induce the onset of hepatic erythropoiesis in mice.

Histopathological features of livers and blood chemical values in cows with abomasal displacement were investigated. Liver biopsy samples were collected during redressment operations in 92 cows with abomasal displacement, and the samples were stained with haematoxylin and eosin or periodic acid Schiff (PAS). Blood was collected for chemical tests. Livers were histopathologically divided into the following four types: normal histology cases (21%), fatty degeneration cases (36%), cloudy swelling cases (19%) and fatty degeneration cases with cloudy swelling (24%). The number of PAS-positive samples was significantly higher in the normal histology group and significantly lower in the severe fatty degeneration group and severe cloudy swelling group. Cows with fatty degeneration had significantly higher levels of serum 3-hydroxybutyric acid, non-esterified fatty acid and aspartate aminotransferase than did those with cloudy swelling or normal histology. The results indicate that the morbid conditions of cows with abomasal displacement can be classified into four types.

A case of autoimmune hepatitis (AIH) complicated by primary sclerosing cholangitis (PSC) in a 36-year-old woman is reported. AIH overlapping with PSC has been rarely reported, and to the best of our knowledge, there have been no reports in Japan. Based on the criteria for diagnosis of AIH and on typical endoscopic retrograde cholangiograph (ERC) findings, the patient was diagnosed as having AIH overlapping with PSC. Her transaminase levels normalized within 1 month after administration of prednisone, azathioprine and ursodeoxycholic acid, but her cholestatic enzyme level remained elevated. The effect of treatment on the cholestatic features is thought to be an important factor for predicting the prognosis of AIH overlapping with PSC.

Stronger neo-minophagen C (SNMC), a glycyrrhizin (GL) preparation, has been used for the treatment of chronic viral hepatitis. It has been reported that a single administration of SNMC induced the activation of hepatic lymphocytes in number and function in animal studies. However, it is still unknown how SNMC augments the cytotoxic function and why such augmentation of cytotoxicity occurs in the liver and other organs. In this study, SNMC was daily injected into mice (2 mg GL/day/mouse) for 2 weeks. A significant augmentation of cytotoxicity mediated by NK cells, NKT cells and TNFalpha was demonstrated mainly in the liver. The presence of TNFalpha-mediated cytotoxicity in the liver was demonstrated for the first time. In contrast to CD8+ cytotoxic T cells (CD8+ CTL), all these cytotoxicities were preexistent in lymphocytes without the immunization of a specific antigen or alloantigens. NK cytotoxicity was mediated by a perforin system, while NKT cytotoxicity was mediated by a Fas ligand system. The present results suggest that the entire cytotoxic function mediated by hepatic lymphocytes was simultaneously augmented by SNMC.

Athymic nude mice carry neither conventional T cells nor NKT cells of thymic origin. However, NK1.1(-)TCR(int) cells are present in the liver and other immune organs of athymic mice, because these lymphocyte subsets are truly of extrathymic origin. In this study, we examined whether extrathymic T cells had the capability to protect mice from malarial infection. Although B6-nu/nu mice were more sensitive to malaria than control B6 mice, these athymic mice were able to survive malaria when a reduced number of parasitized erythrocytes (5 x 10(3) per mouse) were injected. At the fulminant stage, lymphocytosis occurred in the liver and the major expanding lymphocytes were NK1.1(-)TCR(int) cells (IL-2Rbeta(+)TCRalphabeta(+)). Unconventional CD8(+) NKT cells (V(alpha)14(-)) also appeared. Similar to the case of B6 mice, autoantibodies (IgM type) against denatured DNA appeared during malarial infection. Immune lymphocytes isolated from the liver of athymic mice which had recovered from malaria were capable of protecting irradiated euthymic and athymic mice from malaria when cell transfer experiments were conducted. In conjunction with the previous results in euthymic mice, the present results in athymic mice suggest that the major lymphocyte subsets associated with protection against malaria might be extrathymic T cells.

It has been reported that human CD161 (NKR-P1A)+ T cells are counterparts of murine natural T (NT) cells and predominantly accumulate in the liver. However, NT cells in the human intestine have not been well analysed. The aim of this study was to assess the existence of NT cells in human intestinal epithelium and determine their phenotypical characterization. Intra-epithelial lymphocytes (IEL) were isolated from surgical specimens (jejunum, ileum and colon). The surface phenotype of IEL was analysed using a FACScan and compared with that of mononuclear cells (MNC) from other organs. CD161+ T cells were abundant in human intestinal epithelium as well as the liver. The majority of CD161+ T cells in IEL were CD8+ cells. About 50% of CD161+ T cells in hepatic lymphocytes (HL) expressed CD56, whereas only 14% of CD161+ T cells in IEL expressed CD56. The jejunum showed the greatest abundance of CD161+ T cells among the intestinal regions investigated. These results suggest that CD161+ T (NT) cells predominantly exist in human intestinal epithelium and may play an important role in local immunity.

Background/aims: To develop a specific isolation method of hepatic sinusoidal endothelial cells (SEC), we applied the immunomagnetic method using a monoclonal antibody (SE-1) that recognizes a membranous antigen expressed only in rat SEC., Methods: Cells were isolated by incubating mixed non-parenchymal cells, which were obtained by collagenase digestion of the liver, with SE-1-conjugated superparamagnetic polystyrene beads. The conventional Percoll method was also performed in parallel to compare with the immunomagnetic method. The isolated cells were cultured on glass coverslips coated with type I collagen in the presence of various growth factors for 6 days., Results: Approximately 98% of the isolated cells were positive for SE-1 and the contamination of Kupffer cells or stellate cells was less than 1%. The purity was significantly better than that obtained by the Percoll method. The cultured cells showed typical SEC features, such as sieve plates and uptake of acetylated low-density lipoprotein. Although the cells continuously underwent apoptotic cell death after 2 days, they started robust cell growth after 3 days and were well maintained during the culture period., Conclusions: Our simple and specific isolation method enables us to culture SEC with high purity and should be useful for the biological analysis of SEC.