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J M Neuberger

Publications and source records attributed to J M Neuberger.

At least 19 recordsLinked to original sources
PubMed1992

Detection of circulating intercellular adhesion molecule-1 in chronic liver diseases.

The leucocyte adhesion molecule intercellular adhesion molecule-1 is induced on bile ducts in patients with primary biliary cirrhosis and primary sclerosing cholangitis and may be involved in targeting immune damage to these structures. It has recently been reported that, when activated, in vitro lymphocytes release a soluble form of intercellular adhesion molecule-1 that can also be detected in human serum. Because it is functionally active, this circulating intercellular adhesion molecule-1 might play a role in regulating inflammation by blocking adhesion. We used an enzyme-linked immunosorbent assay to detect circulating intercellular adhesion molecule-1 in the serum of patients with primary biliary cirrhosis and primary sclerosing cholangitis. Levels of circulating intercellular adhesion molecule-1 were markedly elevated in primary biliary cirrhosis and primary sclerosing cholangitis when compared with other chronic liver diseases. Circulating intercellular adhesion molecule-1 is probably derived from activated lymphocytes rather than from bile ducts because biliary epithelial cells from patients with primary biliary cirrhosis did not release circulating intercellular adhesion molecule-1 when stimulated to express the membrane-bound molecule in vitro. These studies are the first to demonstrate circulating intercellular adhesion molecule-1 in chronic inflammatory diseases that are characterized by strong tissue expression of intercellular adhesion molecule-1 and as such suggest a potential immunoregulatory role for circulating adhesion molecules. The very high levels detected in primary biliary cirrhosis and primary sclerosing cholangitis probably reflect lymphocyte activation, which is further evidence of immune pathogeneses for these diseases.

Bilirubin↗
PubMed1992

Endothelial cell damage in primary biliary cirrhosis: influence of cholestasis and immunological mechanisms.

In a study looking for evidence of endothelial cell damage in primary biliary cirrhosis, serum from patients was found to be significantly more cytotoxic to cultured endothelial cells in vitro than normal control serum (P less than 0.001). Serum also contained higher levels of von Willebrand factor antigen (vWFAg, a specific product of the endothelium) than control serum (P less than 0.001). Cytotoxicity correlated with serum levels of vWFAg (P less than 0.05) and with serum bilirubin (P less than 0.05). No correlations were found between cytotoxicity and circulating immune complexes, C-reactive protein or CH50. The study was controlled by serum from patients with other liver diseases. In these samples vWFAg (P less than 0.003), and bilirubin levels (P less than 0.001) were also raised relative to normal controls. vWFAg levels again correlated with levels of bilirubin (P less than 0.05). Tissue culture experiments showed that purified bilirubin was cytotoxic to human umbilical vein endothelial cells and induced the release of vWFAg. The case report of a patient with obstructive jaundice again indicated that levels of bilirubin and vWFAg were related. These results suggest that endothelial cell damage occurs in both primary biliary cirrhosis and to a lesser extent in other liver diseases, and may be mediated by cholestasis, not by humoral immunological mechanisms.

Bilirubin↗
PubMed1992

Liver disease in a district hospital remote from a transplant centre: a study of admissions and deaths.

The profile of liver disease admissions and associated deaths in a district general hospital was studied to determine whether patients with end stage liver disease are appropriately referred for consideration of liver transplantation. Admission details were provided by the Office of Population Censuses and Surveys (OPCS) and their accuracy was assessed by case note analysis. According to OPCS, 77 patients with liver disease were admitted on 113 occasions between 1 January 1987 and 31 December 1989. The case notes of 74 (96%) were retrieved and examined. Only 64 (86%) had primary liver disease. Twenty four (31%) died of liver failure. Alcohol was the aetiological agent in two thirds. According to accepted criteria, 11 patients were suitable for liver transplant assessment but only three had been referred to a transplant centre. Of the remaining eight, five died during the study period. Two of the three patients referred died without transplantation; one underwent transplant and survived. There is discrepancy between OPCS data and true disease aetiologies, with approximately 40% under reporting of alcoholic liver disease. If this population is representative of the situation nationally, substantial numbers of patients with end stage liver disease might benefit from liver transplantation, but are not referred to a centre.

England↗
PubMed1992

Human intrahepatic biliary epithelial cells proliferate in vitro in response to human hepatocyte growth factor.

In previous studies, intrahepatic human biliary epithelial cells (BEC) were isolated in high purity. However, these cells demonstrated only limited growth responses. Here we report that human BEC proliferate in response to human hepatocyte growth factor (hHGF), retain BEC-specific phenotype, and can be serially passaged. BEC showed dose-dependent growth in response to 0.01-100 ng/ml hHGF. The maximum S-phase labeling index reached 40% with half-maximal stimulation at 1 ng/ml. The response of cells from normal and primary biliary cirrhotic liver to hHGF was similar. Cultures were immunostained with specific antibodies and then processed for [3H]thymidine autoradiography. Proliferating cells expressed BEC-specific markers (HEA125 and CK-19), but were negative for desmin and factor VIII-related antigen. Occasional vimentin-positive cells were observed, but these were nonproliferative. In conclusion, cells responding to hHGF were clearly BEC in origin. The observation that HGF is mitogenic for BEC as well as hepatocytes has important implications. First, greater yields of intrahepatic BEC are available for subsequent studies of the pathogenesis and etiology of diseases of the biliary epithelium. Secondly, some means of regulating the cellular response to HGF in vivo must operate, in that HGF levels rise early after partial hepatectomy and yet BEC proliferate 24 h later than hepatocytes.

Animals↗
PubMed1992

Orthotopic liver transplantation for hepatic GVHD following allogeneic BMT for chronic myeloid leukaemia.

A 21-year-old man who had an HLA-identical sibling donor BMT for chronic myeloid leukaemia developed grade IV acute GVHD of the liver that was unresponsive to corticosteroids and anti-IL2 receptor monoclonal antibody. He was treated with an orthotopic liver transplant and is currently well 6 months later with normal liver function and no evidence of GVHD in the transplanted liver.

Adult↗
PubMed1991

A 51Cr release cytotoxicity assay for use with human intrahepatic biliary epithelial cells.

Human intrahepatic biliary epithelial cells are important immune targets in a variety of hepatobiliary diseases particularly primary biliary cirrhosis and primary sclerosing cholangitis. The ability to isolate and maintain these cells in short term primary tissue culture has permitted us to develop an in vitro cytotoxicity assay for the study of these cells as potential targets to a variety of toxic stimuli. We have therefore established a chromium-51 (51Cr) release cytotoxicity assay for use with primary cultures of human intrahepatic biliary epithelial cells. The method is simple, reproducible and is more sensitive than dye exclusion, light microscopy and release of lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase.

Alanine Transaminase↗
PubMed1991

The effect of bile salts on human vascular endothelial cells.

The uptake and release of radiochromium from adult human vascular endothelial cells in culture was employed to determine the relative toxicity of different bile salts. Endothelial cells after pre-incubation with 51Cr for 18 h were incubated with bile salts for 24 h and percentage chromium release was taken as a measure of toxicity to cells. Lithocholic acid (LC) (potassium salt) was cytotoxic at concentrations greater than 50 microM. However, LC glucuronide, sulfate and the beta-epimer were progressively less toxic with toxicity seen at concentrations of 60, 110 and 180 microM, respectively. The greatest cytotoxic effect was observed with glycolithocholic acid (GLC) (potassium salt) which was toxic at every concentration tested (20-200 microM). Sulfation abolished the toxic effect of GLC. At the concentrations employed for the assay (between 20 and 240 microM) GLC sulfate (disodium salt), taurolithocholic acid sulfate (disodium salt), cholic acid (sodium salt), glycocholic acid (sodium salt), deoxycholic acid (sodium salt) and ursodeoxycholic acid (sodium salt) were not cytotoxic. The 51Cr release cytotoxicity assay was validated with lactate dehydrogenase leakage from endothelial cells with a good correlation (r = 0.87). These data confirm in a human cellular system that LC and its conjugates were the most toxic of the bile salts tested and explains its pathophysiological importance in hepatobiliary disease. It also suggests that biotransformation by either sulfation or beta-epimerisation of bile salts especially of LC, as occurs in patients with intrahepatic or extrahepatic biliary obstruction or severe cholestasis, is hepatoprotective.

Bile Acids and Salts↗
PubMed1991

New monoclonal antibodies reacting with bile ducts: further insights into the pathogenesis of bile ductular proliferation in biliary diseases.

We have produced a range of monoclonal antibodies which stain human intrahepatic bile ducts of different sizes. Amongst 26 monoclonal antibodies produced, five clones reacted specifically with bile ducts of different sizes, of which three have been maintained in culture and their viability following freezing and thawing confirmed. Staining patterns varied between normal adult liver tissue, normal fetal liver tissue and a variety of hepatobiliary diseases. The antibodies provide further evidence of the immunological heterogeneity of the human intrahepatic biliary tree and support the hypothesis that proliferating bile ductules are derived from periseptal hepatocytes. The preparation of the antibodies, their staining reactions in normal adult, normal fetal and a variety of liver diseases are described.

Adult↗
PubMed1991

Role of endoscopic retrograde cholangiopancreatography after orthotopic liver transplantation.

Twelve of 178 (7%) liver transplant patients underwent endoscopic retrograde cholangiopancreatography (ERCP) after transplantation. The indications for ERCP were persistent or late onset cholestasis, recurrent cholangitis, and suspected biliary leaks or strictures. The time between transplantation and ERCP ranged from 44 to 330 days (median 153 days). Biliary complications diagnosed by ERCP included biliary sludge in the form of casts, calculi, or debris (n = 7); bile leaks (n = 2); a biliary stricture (n = 1), and complete biliary obstruction (n = 1). One patient had a normal cholangiogram after transplantation. Biliary sludge was detected by ultrasound before ERCP in only one of six patients. Eight patients underwent endoscopic papillotomy, followed by clearance of biliary sludge in four and dilatation of a biliary stricture in one. Two patients bled after papillotomy but neither required surgical intervention. At a median follow up of 1.2 years (range 0.5-2.8 years), nine patients are well and three have died. ERCP provides both accurate diagnosis of biliary complications after liver transplantation and treatment that obviates the need for additional surgery in selected patients.

Adult↗
PubMed1991

Increased expression of intercellular adhesion molecule 1 on bile ducts in primary biliary cirrhosis and primary sclerosing cholangitis.

It has been suggested that immunological mechanisms involving lymphocyte-mediated damage are important in the characteristic bile-duct damage that occurs in primary biliary cirrhosis and primary sclerosing cholangitis. Because adhesion is necessary for the interaction of lymphocytes with their target structures, we have studied the expression of intercellular adhesion molecule 1, a ligand for the leukocyte adhesion receptor lymphocyte function-associated antigen 1 in the liver of patients with primary biliary cirrhosis and primary sclerosing cholangitis. Strong expression of intercellular adhesion molecule 1 was seen on interlobular bile ducts and proliferating bile ductules in both conditions. In primary biliary cirrhosis, medium-sized ducts, which are spared by the disease, were negative. Minimal bile-duct staining was seen in conditions in which bile-duct damage is not a major feature, such as nonbiliary cirrhosis and acute liver diseases. In patients with cirrhosis from any cause, strong expression of intercellular adhesion molecule 1 was detected on the periseptal hepatocytes adjacent to new connective tissue. The intensity of immunohistochemical staining was recorded using a semiquantitative visual scoring system that was subsequently validated quantitatively by confocal laser scanning microscopy. The expression/induction of intercellular adhesion molecule 1 on bile ducts may be important in the pathogenesis of bile-duct damage in primary biliary cirrhosis and primary sclerosing cholangitis and is further evidence to support an immune pathogenesis in these two conditions. Furthermore, the induction of intercellular adhesion molecule 1 on hepatocytes may be an important factor in the liver-cell damage and fibrosis that occur during the development of cirrhosis.

Bile Ducts↗
PubMed1991

Distribution of dihydrolipoamide acetyltransferase (E2) in the liver and portal lymph nodes of patients with primary biliary cirrhosis: an immunohistochemical study.

The reason for the close association between primary biliary cirrhosis and the appearance of antibodies that recognize the E2 component of pyruvate dehydrogenase complex is not understood. The distribution of the three pyruvate dehydrogenase complex subunits was examined in the liver and lymph nodes of patients with primary biliary cirrhosis, patients with other liver diseases and normal subjects by immunohistochemistry using affinity-purified antibodies. Intensity of staining was assessed semiquantitatively and validated by scanning laser confocal microscopy. In primary biliary cirrhosis tissue, the E2 staining pattern did not parallel the reported distribution of mitochondria. E2 staining in biliary epithelial cells was consistently stronger than in hepatocytes. In primary biliary cirrhotic liver, staining of biliary epithelium was significantly stronger than in normal or other liver disease controls; many bile ducts in primary biliary cirrhotic liver demonstrated very high intensity, diffuse distribution of stain. No differences in staining intensity were seen between perivenular hepatocytes in primary biliary cirrhotic liver and those in controls; periportal hepatocytes in primary biliary cirrhotic liver were, however, more intensely stained than perivenular cells. In primary biliary cirrhotic portal lymph nodes, a subset of macrophages showed high-intensity, diffuse distribution of stain. By contrast, staining with antibodies to E1 and E3 (other components of pyruvate dehydrogenase complex) produced uniform-intensity, mitochondrial distribution both in primary biliary cirrhosis and control tissue. The increased intensity of E2 in primary biliary cirrhotic tissue could be explained in terms of abnormal metabolism of E2 by biliary epithelial cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetyltransferases↗
PubMed1991

Growth of normal human hepatocytes in primary culture: effect of hormones and growth factors on DNA synthesis.

Although the ability of hormones and growth factors to stimulate DNA synthesis in rat hepatocytes has been investigated extensively, no such study of human hepatocytes has been reported. Here we describe a series of experiments to identify those factors that regulate human hepatocyte DNA synthesis in vitro and which therefore may play a role in the control of human liver regeneration. Human hepatocytes were isolated from normal liver tissue obtained after graft reduction for transplantation into pediatric recipients. Cells were maintained in culture for up to 5 days, and DNA synthesis was determined. Hydroxyurea reduced [3H]thymidine incorporation into DNA by 95%, indicating replicative DNA synthesis. As previously found with rat hepatocytes, epidermal growth factor and transforming growth factor-alpha stimulated DNA synthesis at low nanomolar concentrations; transforming growth factor-alpha was slightly more potent. Although the overall rate of thymidine incorporation was lower than that for rodent cells, human hepatocytes were sensitive to lower concentrations of these growth factors, and the degree of stimulation was similar. Conversely, transforming growth factor-beta inhibited DNA synthesis at low picomolar levels. By contrast (unlike rat hepatocytes), arginine-vasopressin failed to initiate or potentiate DNA synthesis in human cells. These data indicate that normal human hepatocytes can respond to low concentrations of growth promoters or inhibitors, previously shown to have activity on rat hepatocytes. These factors may then play a role in control of human liver growth. However, important species differences are apparent, highlighting the limitations of extrapolating from animal studies to humans.

Animals↗