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Several studies have demonstrated that In used in medicine has several impacts on organs like spleen and lungs after its systemic administration. In the present study, ultrastructural and microanalytical methods were used to investigate the impact of the presence of this element in the intestinal mucosa, the liver, the kidney and the testicle after its administration in two ways. After intraperitoneal administration, In was selectively concentrated in the lysosomes of hepatocytes, of tubular proximal convoluted cells and of Sertoli and Leydig cells. After intragastric administration, ultrastructural study showed that this element was concentrated in the lysosomes of duodenal enterocytes. Microanalytical methods showed that In was precipitated in those organelles in the form of insoluble phosphate salts. Similarly to other studies, it seemed that since In is a foreign element for the organism, it was precipitated in lysosomes, very probably due to the activity of an intralysosomal enzyme the acid phosphatase, to avoid its invasion to organism via the blood. This mechanism of precipitation of the mineral elements is of great interest in the process of defensive reaction of the organism against intoxication by foreign elements.

Background and Study Aims: Confocal endomicroscopy is a unique novel tool for in vivo histology in humans. Due to limitations imposed by the form of the equipment and by sterilization workflows, its use has been limited to the gastrointestinal tract so far. We have developed a rigid miniaturized probe for confocal endomicroscopy of the human liver during laparoscopy., Patients and Methods: To assess the feasibility and potential clinical value of this new system (diameter 6.3 mm), 25 patients with liver disease were examined during routine minilaparoscopy under conscious sedation., Results: Subsurface serial images (from surface to 250 microm) were generated in real time after fluorescein injection, permitting visualization of hepatocytes, bile ducts, sinusoids, and collagen fibers in vivo. Typical appearances of liver diseases were identified. Confocal diagnosis of moderate-to-severe steatosis and pericellular fibrosis correlated well with histopathologic analysis of subsequent biopsies (83.3 % and 84.6 %, respectively). In addition, intra-abdominal structures such as gallbladder, omentum, and stomach were analyzed by endomicroscopy., Conclusions: A miniaturized imaging system for confocal laparoscopy allowed in vivo microscopic analysis of healthy and diseased human liver for the first time during ongoing minilaparoscopy. Although such in vivo imaging does not yet compete with conventional histopathology, this novel confocal laparoscopy system may be of future relevance for immediate morphodynamic analysis in liver disease and the targeting of biopsies in vivo.

The behaviour of the intestinal mucosa and of the liver after an administration of a gadolinium salt has been studied in the Wistar rat using transmission electron microscopy, ion mass spectrometry, and electron probe microanalysis. Six hours after parenteral administration, gadolinium is concentrated with phosphorus in the lysosomes of hepatocytes and Küppfer cells. Six hours after its oral administration, gadolinium is detected in the duodenal enterocytes lysosomes, but never in those of the liver cells. It is suggested that this mechanism of local concentration limits the diffusion through the digestive barrier of foreign elements, some of them being toxic and none of them having a physiological function.

Hepatic failure after liver resection is a complication that is dreaded by surgeons and has a poor outcome. Inadequate functional reserve of the remaining liver parenchyma leads to the inability to regenerate and finally to the progression of liver failure. In order to predict the functional reserve of the remaining liver parenchyma, many different liver function tests have been established. Basis for most liver function assessments are metabolic liver functions such as cytochrome p450 dependent pathways or the extraction and biliary excretion of dye. Nuclear imaging of the liver parenchyma does not only allow visualisation of the liver but also accumulation of information on hepatocyte volume that might be a better predictor for the hepatic reserve and the regenerative capacity compared to the liver volume alone. However, to date no single method has been proven to be able to predict safe limits of resectability. If an underlying liver disease is excluded the resectability is mostly limited by volumetric analysis and technical feasibility of liver resection. In patients with underlying liver disease cirrhosis should be excluded. In case of liver cirrhosis, only Child-Pugh-Turcott A patients with normal bilirubin levels and without portal hypertension should be considered for liver resection.

Fulminant hepatic failure is an uncommon but life-threatening adverse reaction to antibiotic therapy. Reported here is a case of severe liver injury associated with ciprofloxacin administered for treatment of a gram-negative infection in a 79-year-old female. The patient presented with metabolic acidosis 48 hours after the first ciprofloxacin intake. Symptoms resolved after cessation of ciprofloxacin therapy. This report highlights an uncommon side effect of a commonly used antimicrobial agent.

Background and Objective: The aim of this study was to evaluate whether the presence of SLA/LP-autoantibodies in PBC-patients gives evidence for a secondary AIH, also called AIH/PBC-overlap-syndrome., Patients and Methods: Out of 233 consecutive patients with PBC who had been followed between October 1980 and April 2000, we evaluated the data of anti-SLA/LP-positive patients and compared them to patients with an anti-SLA/LP-negative AIH/PBC overlap syndrome as well as to patients with a classical course of AIH and PBC., Results: In total we could identify nine PBC patients with anti-SLA/LP antibodies (six women/three men) or 3.9% of the study population, Anti-SLA/LP-positive PBC patients were slightly younger at diagnosis in comparison to anti-SLA/LP-negative PBC-patients (49.9 vs. 53.2 years). Transaminases and gamma-globulins were significantly higher in anti-SLA/LP-positive PBC-patients in comparison to anti-SLA/LP-negative PBC-patients (mean: 235 vs. 55 IU/l and 27.6 vs. 19.5 g/l). Anti-SLA/LP-positive patients significantly more frequently had an HLA-type that is characteristic for AIH (B8; DR3; DR4). Immunosuppressive therapy reduced inflammatory activity and cholestasis significantly. Relapses were frequent after reduction or discontinuation of immunosuppressive therapy., Conclusion: The presence of SLA/LP autoantibodies in PBC patients has a high specificity for a secondary AIH (AIH/PBC overlap syndrome). These patients have a good response to immunosuppressive therapy. The autoantibody profile and immunogenetics may help in future to identify PBC patients that benefit most from immunosuppressive therapy.

Hemochromatosis and Wilson disease (WD), characterized by the excess hepatic deposition of iron and copper, respectively, produce oxidative stress and increase the risk of liver cancer. Because the frequency of p53 mutated alleles in nontumorous human tissue may be a biomarker of oxyradical damage and identify individuals at increased cancer risk, we have determined the frequency of p53 mutated alleles in nontumorous liver tissue from WD and hemochromatosis patients. When compared with the liver samples from normal controls, higher frequencies of G:C to T:A transversions at codon 249 (P < 0.001) and C:G to A:T transversions and C:G to T:A transitions at codon 250 (P < 0.001 and P < 0.005) were found in liver tissue from WD cases, and a higher frequency of G:C to T:A transversions at codon 249 (P < 0.05) also was found in liver tissue from hemochromatosis cases. Sixty percent of the WD and 28% of hemochromatosis cases also showed a higher expression of inducible nitric oxide synthase in the liver, which suggests nitric oxide as a source of increased oxidative stress. A high level of etheno-DNA adducts, formed from oxyradical-induced lipid peroxidation, in liver from WD and hemochromatosis patients has been reported previously. Therefore, we exposed a wild-type p53 TK-6 lymphoblastoid cell line to 4-hydroxynonenal, an unsaturated aldehyde involved in lipid peroxidation, and observed an increase in G to T transversions at p53 codon 249 (AGG to AGT). These results are consistent with the hypothesis that the generation of oxygen/nitrogen species and unsaturated aldehydes from iron and copper overload in hemochromatosis and WD causes mutations in the p53 tumor suppressor gene.

Regulation of the homeostatic balance between cell proliferation and programmed cell death, apoptosis, is essential for development and maintenance of multicellular organisms. Apoptosis is a genetically and evolutionarily highly conserved process. Analysis of the molecular mechanisms of apoptosis has led to a better understanding of many human diseases. Notably in cancer, but also in infectious or autoimmune disease, a deficiency in apoptosis is one of the key events in pathophysiology. On the other hand, overefficient apoptosis, as observed in fulminant liver failure, may be equally harmful for the organism indicating that a tight regulation of the apoptotic machinery is essential for survival. The execution of apoptosis may be initiated by many different signals, either from within or outside the cell involving ligand-receptor interactions, as has been shown for Fas/Fas-ligand, TNF-alpha/TNF-receptor or TGF-beta/TGF-receptor, or potentially by more unspecific signals such as ceramide or DNA damage. During the modulation phase of apoptosis many different genes such as p53, c-myc or Bcl-2/Bax have been shown to able to shift the balance either to cell survival or cell death.

The subcellular localization of lanthane was studied using two microanalytic methods. 1.) The election microprobe method showed that lanthane is concentrated in the lysosomes of the hepatocytes and the spleen associated with phosphorus. 2.) The ion microanalysis showed that lanthane is selectively precipitated in the lysosomes of the enterocytes optical part. This mechanism of selective precipitation initially prevents the diffusion of this toxic element in the organism and then permits its elimination digestively after desquamation of enterocytes in apoptosis in the intestinal lumen.

The replication cycle of the hepatitis B virus (HBV) is still incompletely understood. In particular, the early steps of the viral life cycle, such as absorption, penetration, uncoating, and nuclear translocation require further clarification. In this study we performed infection experiments with HBV in primary human hepatocyte cultures. To further elucidate the possible mechanism of virus uptake, infection experiments were performed at different pH levels, after pretreatment of viral particles with acidic buffers and in the presence of lysosomotropic agents (chloroquine and ammonium chloride, respectively). Using a selective PCR technique which discriminates between input virus DNA and the earliest replicative form, we could demonstrate viral replication 36 hr after inoculation. HBV was taken up most efficiently at a pH of 7.4. Infection was still successful after pretreatment of viral particles at low pH and was unaffected by the presence of lysosomotropic agents. In conclusion, this suggests HBV to be a pH-independent virus.

Unlabelled: A young male suffering from fulminant hepatic failure of unknown origin had an auxiliary partial orthotopic liver transplantation performed. The aim of the present study was to test the performance of factor analysis of medical image sequences (FAMIS) in the post-transplantation monitoring of the graft and native liver functions., Methods: Four successive hepatobiliary studies within 63 days following transplantation using 99mTc-mebrofenin were performed (on days 13,20,34,63). The 60 one-minute dynamic series were subjected to two successive FAMIS procedures., Results: For all studies, except the first, FAMIS was able to extract three factor couples (factor images and factors or curves) those of the native liver, the graft liver and the biliary region. The factors time evolution in uptake and excretion components showed the correlations between clinical status and scintigraphic results and helped interpretation of biochemical tests., Conclusion: The possible utility of systematic liver transplant monitoring by radionuclide hepatobiliary imaging in identification of complications requiring medical or surgical intervention in graft livers was demonstrated. Furthermore, our study showed the functional recovery potential of the native liver in patients suffering from fulminant hepatitis.

Apoptosis occurs in the normal liver and in various forms of liver disease. The CD95 (APO-1/Fas) (CD95) receptor mediates apoptosis, and liver cells in animal models are acutely sensitive to apoptosis initiated by this receptor. We have used primary human hepatocytes as a model system to investigate CD95-mediated apoptotic liver damage. Treatment of fresh human hepatocytes with low concentrations of agonistic antibodies against CD95 resulted in apoptosis of > 95% of the cultured liver cells within 4 and 7.5 h. Immunohistology of a panel of explanted liver tissues revealed that hepatocytes in normal livers (n = 5) and in alcoholic cirrhosis (n = 13) expressed low constitutive levels of CD95. CD95 receptor expression was highly elevated in hepatocytes in hepatitis B virus-related cirrhosis (n = 9) and in acute liver failure (n = 8). By in situ hybridization CD95 ligand messenger RNA expression was absent in normal liver but detected at high levels in livers with ongoing liver damage. In cases of hepatitis B virus-related cirrhosis and acute hepatic failure, ligand expression was found primarily in areas with lymphocytic infiltration. In contrast, in patients with alcoholic liver damage, high CD95 ligand messenger RNA expression was found in hepatocytes. These findings suggest that liver destruction in hepatitis B may primarily involve killing of hepatocytes by T lymphocytes using the CD95 receptor-ligand system. In alcoholic liver damage, death of hepatocytes might occur by fratricide and paracrine or autocrine mechanisms mediated by the hepatocytes themselves.

The rare earth gadolinium (Gd) is used in modern industry. Solubilized DTPA Gd and DOTA Gd complexes are used as contrast media in nuclear magnetic resonance imaging. In order to determine the subcellular localization of Gd, rats were injected intraperitoneally with Gd nitrate. Two microanalytic methods, ion microanalysis and electron microprobe, enabled the distribution and the intracellular localization of Gd to be determined in the liver, spleen, bone marrow, kidneys and lung. The results showed: a) a punctual distribution of Gd in the tissues (liver, spleen, bone marrow and lung) as observed by ion microscopy; b) a selective concentration of Gd in the lysosomes of macrophages of the liver (hepatocytes), spleen (macrophages), bone marrow (macrophages) and lung (phagocyte cells), as determined by electron probe X-ray microanalysis. In all these sites the Gd is associated to phosphorus. Results are compared to those found for other rare earths and metal elements.

The interaction of selenium with elements of group 1b of the periodic system, i.e. copper, silver, and gold was studied. Electron probe microanalysis was used to detect elements in intracellular organelles. Administration of copper, silver, or gold salts (the latter being used in chrysotherapy) showed that these elements were concentrated in the lysosomes of the liver or kidney in the presence of sulfur. Silver salts were also precipitated in glomerular basement membranes. The action of selenium enhances this intralysosomal process of concentration and precipitation. Sulfur and selenium are detected in the lysosome and this makes identification of the precipitate difficult. The action of selenium, which consists in removing toxic elements from the systemic circulation and concentrating them in the lysosomes, is in most cases beneficial for the organism. This mechanism, which has already been studied for arsenic, is extended in this study to other elements.

High-density lipoprotein cholesteryl esters are taken up by many cells without simultaneous uptake of high-density lipoprotein apolipoproteins. This selective uptake was investigated in human hepatocytes in primary culture. Human high-density lipoprotein-3 (density, 1.125 to 1.21 gm/ml) was radiolabeled in both its apolipoprotein and in its cholesteryl ester moiety; uptake of these high-density lipoprotein3 tracers by hepatocytes was investigated. Apparent high-density lipoprotein3 particle uptake as measured with the cholesteryl ester tracer was in excess of that from the apolipoprotein tracer, indicating selective uptake of high-density lipoprotein3 cholesteryl esters by hepatocytes. This selective uptake is a regulated pathway in hepatocytes, as demonstrated by an inverse relationship between cell cholesterol and the rate of selective uptake. Studies on the mechanism of selective uptake have used inhibitors such as monensin, chloroquine, heparin, and a monoclonal antibody directed against low-density lipoprotein receptors. These experiments provide no evidence for a role of cell-secreted apolipoprotein E, endocytosis or retroendocytosis in selective uptake. The intracellular fate of high-density lipoprotein3-associated cholesteryl esters was investigated with [3H]cholesteryl oleate-labeled high-density lipoprotein3. Hepatocytes hydrolyzed [3H]cholesteryl oleate internalized from labeled high-density lipoprotein3; this catabolism was not inhibited by the presence of chloroquine. In parallel hepatocytes were incubated with [3H]cholesteryl oleate-labeled low-density lipoprotein. Cells hydrolyzed [3H]cholesteryl oleate taken up with low-density lipoprotein; however, this hydrolysis was inhibited by chloroquine, indicating lysosomal low-density lipoprotein cholesteryl ester catabolism. These experiments show that high-density lipoprotein3 cholesteryl esters selectively taken up by hepatocytes are hydrolyzed independently from the classical lysosomal catabolic pathway. The question was addressed if selective uptake mediates a net mass uptake of cholesterol rather than an isotope exchange phenomenon. Incubation of hepatocytes with high-density lipoprotein-3 suppressed endogenous sterol synthesis from sodium [14C]acetate. Hepatocytes were incubated in the presence of high-density lipoprotein3; medium cholesteryl esters decreased as a result of incubation with hepatocytes. These results show a net mass delivery of high-density lipoprotein cholesteryl esters to hepatocytes. In conclusion, the pathway for selective uptake of high-density lipoprotein cholesteryl esters could be demonstrated in human hepatocytes in primary culture. A role for selective uptake in high-density lipoprotein-mediated cholesterol delivery to the liver in human beings in vivo is proposed.

Background/aims: Studies on the interaction of hepatitis B virus (HBV) with its host cell require a suitable tissue culture system. This study used primary adult hepatocytes from healthy human liver tissue to establish productive infection in vitro., Methods: Hepatocytes were inoculated overnight with HBV. Production of viral proteins was assessed by radioimmunoassay and by [35S]methionine labeling, and production of viral DNA was assessed by Southern blotting and endogenous polymerase assay., Results: Secretion of high levels of hepatitis B surface antigen (HBsAg) and low levels of hepatitis B virus e antigen (HBeAg) into the medium was detectable 6 days after infection and reached maximum values after 12 days. Metabolic labeling showed production of viral proteins to be a result of de novo synthesis. The appearance of single-stranded HBV DNA in the cytoplasm of infected cells, typically present in immature cores, indicated viral replication. HBV DNA containing particles possessing an active viral DNA polymerase could be immunoprecipitated from the medium 12 days after infection. An antiserum specific for the preS1 region of the viral envelope was capable to block infection. Presence of dimethyl sulfoxide in the medium greatly improved the yield of viral proteins., Conclusions: Primary adult human liver cells are competent for infection with HBV.

After injection in the rat of soluble neptunium salt, the distribution of this element was studied at the subcellular level by electron microscopy and electron probe microanalysis. Abnormal structures have been observed by electron microscopy in the nuclei of hepatocytes, and the same structures have also been observed in the nuclei of the proximal tubules cells of the kidney. These structures are formed of clusters of very small and dense particles, several nanometers in diameter. The clusters are localized in the central part of the nuclei and they are separate from nucleoli and heterochromatin. Electron probe X-ray analysis of this cluster have shown that they contain neptunium associated with phosphorus. In the cell containing neptunium inclusions, other non specific lesions are also observed (nuclear pycnosis, mitochondrial depletion).

Primary human hepatocytes were used to study bile salt hepatotoxicity and the hepatoprotective potential of ursodeoxycholate in vitro. Hepatocytes were obtained by collagenase perfusion of healthy human liver tissue and were treated with glycochenodeoxycholate for 24 hr 1 day after plating. Clear signs of cytotoxicity were observed at concentrations of about 100 mumol/L glycochenodeoxycholate. Toxicity was determined by release of alkaline phosphatase, gamma-glutamyl transferase, AST, ALT or lactate dehydrogenase into the culture medium, by measuring DNA synthesis of the cultured liver cells and by testing the viability of the hepatocytes using trypan-blue dye exclusion. Addition of ursodeoxycholate, which by itself proved to be of little toxicity, significantly reduced the hepatotoxic effects of glycochenodeoxycholate: 72% +/- 6% of the cells survived treatment with 500 mumol/L glycochenodeoxycholate alone, but addition of 100 mumol/L ursodeoxycholate increased the survival rate to 87% +/- 4% (p less than 0.05). Moreover, all enzymes tested were secreted at a significantly lower level when ursodeoxycholate was present. Similarly, the cellular DNA synthesis was maintained at significantly higher levels as a result of ursodeoxycholate treatment. We conclude that (a) primary human hepatocytes are a suitable model for studying hepatotoxicity of bile salts in vitro, (b) ursodeoxycholate reduces hepatotoxicity of other bile salts and (c) ursodeoxycholate can act hepatoprotectively by itself (i.e., alteration of the metabolism of other bile salts is not necessarily required).

Liver tissue of a female patient who died of dialysis encephalopathy with aluminium intoxication was studied by electron microscopy and X-ray microprobe analysis. Aluminium was present in high concentrations in lipofuscin granules of hepatocytes and associated with severe lesions of most hepatic cells. The Küpffer cells, however, were normal. A similar study conducted in rats intoxicated by soluble aluminium salts showed that aluminium begins to concentrate in the lysosomes of hepatocytes, where it combines with phosphorus to form an insoluble salt.

Rat primary liver cells were used to study taurine and glycine conjugation and sulfation of lithocholate. After addition of [14C]lithocholate to the tissue culture medium, synthesis and excretion of amidated and/or sulfated products were investigated for up to 24 h. After incubation for 1 h, more than 83% of the labeled bile salt was amidated but not sulfated and between 5 and 11% was sulfated, with more than 80% of the sulfated bile salts being also amidated. After 24 h, the proportion of sulfated lithocholate had increased to about 23% and more than 99% of the lithocholate sulfate was additionally conjugated with glycine or taurine. Both sulfates and non-sulfates were preferably amidated with taurine. We conclude that in primary rat hepatocytes, (1) lithocholate is rapidly and almost completely conjugated with glycine or taurine (amidated), whereas sulfation of lithocholate (and its amidates) proceeds slowly and even after 24 h represents only a small proportion of the total lithocholate metabolites, and (2) sulfated and unsulfated bile salts are both preferably amidated with taurine.

Beryllium absorption sites in the kidney and liver of rats have been located and imaged at approximately 70 nm lateral resolution with a scanning ion microprobe utilizing secondary ion mass spectrometry. Embedded sections and lyophilized cryosections of these organs were prepared after in vivo administration of beryllium in soluble form. Beryllium distribution images were correlated with the histological microstructure revealed by CN- images. In the kidney, beryllium concentrates selectively within the nuclei of proximal tubule cells and occasionally within modified podocytes or mesangial cells in the glomerulus. In the liver, beryllium is seen to localize within severely altered lysosomal structures as well as within hepatocyte nuclei. These observations are relevant to understanding aspects of the toxic and carcinogenic properties of absorbed beryllium compounds.

Induction of hepatocyte DNA synthesis in culture by cyproterone acetate (CPA), a potent hepatomitogen in vivo, was studied. Adult rat hepatocytes were grown on collagen gels in primary culture for 3 to 10 d. Epidermal growth factor (EGF) was used as a model inducer to establish appropriate culture conditions. (a) In serum-free medium EGF stimulated a wave of DNA synthesis in 10 to 30% of the hepatocytes. CPA had only a weak effect. (b) Increasing concentrations of newborn bovine serum (NBS) at 5 to 95% progressively inhibited the stimulatory effect of EGF. A similar inhibition was obtained by adding bovine serum albumin; 20% NBS, however, had a slightly stimulatory effect on the induction of DNA synthesis by CPA. (c) Portal rat serum (RS) at concentration of 5 to 95% markedly stimulated DNA synthesis, a plateau being reached between 20 and 95%. EGF had a distinct enhancing effect on DNA synthesis in the presence of 5 and 20% RS but not at 50 and 95%. CPA stimulated DNA synthesis in the presence of 20, 50, and 95% RS in a synergistic way. (d) Mitoses were found after treatment with EGF or with CPA. These results show that CPA can induce DNA synthesis in cultured hepatocytes and that RS contains factors facilitating the response to CPA.

Analytical microscopy was used to study the distribution and chemical composition of thorium deposits in bone marrow and liver after injection of thorium dioxide and thorium nitrate. Thorotrast (thorium dioxide) was identified as being localized in bone marrow macrophages of a patient who had undergone cerebral arteriography forty two years ago. Large thorotrast deposits were also present in liver cells. We show that non-colloidal thorium (thorium nitrate) injected in rats concentrates in a non soluble form in bone marrow macrophages, hepatocytes and Kupffer cells. These deposits of thorium associated with phosphorus can be explained by the formation of thorium phosphate in lysosomes and we demonstrate that they remain in tissue for a long time. Microanalysis was performed with ion microscopy, and electron probe microanalysis by X ray spectrometry, which can identify and localize thorium and associated elements at cellular or intracellular level.

Primary duck hepatocytes obtained from Pekin ducks congenitally infected with duck hepatitis B virus were used to monitor expression of viral proteins and replication of viral DNA in cell culture. Duck hepatitis B virus core antigen, duck hepatitis B virus pre-surface antigen and duck hepatitis B virus DNA were detectable for at least 12 days after cell plating. Whereas expression of duck hepatitis B pre-surface antigen was constant during this time, expression of duck hepatitis B core antigen and of viral DNA rapidly declined. This diminished production of viral components in vitro was paralleled by a change of the hepatocytes toward a fibroblast-like morphology. Supplementation of cell culture medium with 2% dimethyl sulfoxide, a solvent known to maintain the differentiated state of cultured cells, retained competence of the cultured hepatocytes to express duck hepatitis B core antigen and duck hepatitis B virus DNA at high levels. In a second set of experiments, duck hepatitis B virus negative hepatocytes were infected with duck hepatitis B virus from serum of congenitally infected ducks. Dimethyl sulfoxide remarkably improved the competence of cultured duck hepatocytes to become productively infected. This function was maintained for at least 12 days postplating.

The livers of 7 hemodialyzed patients have been studied by electron microscopy and electron probe X-ray microanalysis. In 6 patients dialyzed for a long time (at least 39 months), aluminum has been detected in high concentrations in phagolysosomes of hepatocytes; in these lysosomes aluminum is associated with phosphorus. In 2 of these 6 patients, a very large number of aluminum inclusion bodies were found inside hepatocytes and this aluminum accumulation was associated with severe ultrastructural lesions of the cells. In one patient dialyzed during a short period (4 months) no aluminum accumulation has been observed. In none of the 7 patients was aluminum accumulation detected inside the Küpffer cells. These observations show that the cell which accumulates aluminum in the liver of dialyzed patients is the hepatocyte and not the Küpffer cell and that this accumulation may be associated with serious hepatocellular lesions.

In different tumour entities, expression of the chemokine receptor 4 (CXCR4) has been linked to tumour dissemination and poor prognosis. Therefore, we evaluated, if the expression of CXCR4 exerts similar effects in human hepatocellular carcinoma (HCC). Expression analysis and functional assays were performed in vitro to elucidate the impact of CXCL12 on human hepatoma cells lines. In addition, expression of CXCR4 was evaluated in 39 patients with HCC semiquantitatively and correlated with both, tumour and patients characteristics. Human HCC and hepatoma cell lines displayed variable intensities of CXCR4 expression. Loss of p53 function did not impact on CXCR4 expression. Exposure to CXCL12 mediated a perinuclear translocation of CXCR4 in Huh7/Hep3B cells and increased the invasive potential of Huh7 cells. In HCC patients, CXCR4 expression significantly correlated with progressed local tumours (T-status; P=0.006), lymphatic metastasis (N-status; P=0.005) and distant dissemination (M-status; P=0.009), as well as with a decreased 3-year-survival rate (P=0.01). In summary, strong expression of CXCR4 is significantly associated with progressed hepatocellular cancer.British Journal of Cancer (2006) 95, 210–217. doi:10.1038/sj.bjc.6603251 www.bjcancer.com Published online 4 July 2006 [ABSTRACT FROM AUTHOR]

Background: Interleukin 18 (IL-18) is a cytokine with pleiotropic activity that augments T helper 1 responses and cytotoxic activity of natural killer cells. Methods: To assess the function of IL-18 in vivo, we generated IL-18 transgenic (IL-18 Tg) mice under the control of a CD2 promoter/enhancer construct. Results: Macroscopically, IL-18 Tg mice showed reduced relative liver weight compared with wild-type liltermates. TUNEL assays demonstrated increased hepatocyte apoptosis, and primary hepatocytes isolated from IL-18 Tg mice exhibited an increased spontaneous apoptosis rate. Furthermore, cross linking of Fas increased significantly the apoptosis rate in hepatocytes isolated from wild- type mice but to a much lesser extent in IL-18 Tg mice, suggesting spontaneous activation of the Fas pathway in the latter mice. In fact, in vivo blockade of Fas signal transduction by an adenovirus overexpressing the dominant negative form of the Fas associated death domain rescued hepatocytes from undergoing apoptosis. Finally, adoptive transfer of CD4+> T cells from IL-18 Tg mice but not from wild-type littermates in SCID mice resulted in severe liver failure with massive periportal fibrosis due to hepatocyte apoptosis. Conclusion: IL-18 plays a fundamental role in regulating hepatocyte apoptosis. Furthermore, our transgenic model provides a novel tool to study the mechanisms of IL-18 dependent liver injury in vivo. [ABSTRACT FROM AUTHOR]

Hepatocytes exert pivotal roles in metabolism, protein synthesis and detoxification. Non-parenchymal liver cells (NPCs), largely comprising macrophages, dendritic cells, hepatic stellate cells and liver sinusoidal cells (LSECs), serve to induce immunological tolerance. Therefore, the liver is an important target for therapeutic approaches, in case of both (inflammatory) metabolic diseases and immunological disorders. This review aims to summarize current preclinical nanodrug-based approaches for the treatment of liver disorders. So far, nano-vaccines that aim to induce hepatitis virus-specific immune responses and nanoformulated adjuvants to overcome the default tolerogenic state of liver NPCs for the treatment of chronic hepatitis have been tested. Moreover, liver cancer may be treated using nanodrugs which specifically target and kill tumor cells. Alternatively, nanodrugs may target and reprogram or deplete immunosuppressive cells of the tumor microenvironment, such as tumor-associated macrophages. Here, combination therapies have been demonstrated to yield synergistic effects. In the case of autoimmune hepatitis and other inflammatory liver diseases, anti-inflammatory agents can be encapsulated into nanoparticles to dampen inflammatory processes specifically in the liver. Finally, the tolerance-promoting activity especially of LSECs has been exploited to induce antigen-specific tolerance for the treatment of allergic and autoimmune diseases.