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J M Neuberger

Publications and source records attributed to J M Neuberger.

At least 19 recordsLinked to original sources
PubMed1995

Timing, significance, and prognosis of late acute liver allograft rejection.

Liver allograft rejection is usually divided into acute (cellular) rejection and chronic (ductopenic) rejection. Most cases of acute rejection occur within four weeks of transplantation. There is a paucity of published literature on late acute rejection (LAR) in liver allografts and little is known about factors affecting its occurrence and outcome. To study the predisposing factors, clinical presentation, and prognosis of LAR, data prospectively collected on consecutive adult patients who underwent liver transplantation between 1982 and 1994, were analyzed. LAR was defined as histologically confirmed acute cellular rejection occurring 30 or more days after liver transplantation. Of the 717 patients, 59 (7.5%) had 71 episodes of LAR. Fifty-seven episodes were seen during the first year after transplantation, the remaining occurring between 1 and 6 years. Age, sex, pretransplant diagnosis, donor match of HLA, and blood groups was not associated with risk of LAR. Twenty-seven (38%) episodes were preceded by subtherapeutic blood levels of cyclosporine/FK506 (< 100 ng/ml and < 5 ng/ml, respectively) while an additional 6 (8%) had marginally low blood levels (< 150 ng/ml and < 10 ng/ml, respectively). Treatment with high-dose prednisolone resulted in complete resolution of rejection in 36 (51%) episodes, partial response in 21, and no response in 14 patients. Sixteen patients (27%) developed chronic rejection and graft loss. Development of chronic rejection was not affected by age or sex of the patient, timing of LAR, or histological severity of AR. Delayed response to therapy during an earlier episode of AR, and histological findings of centrilobular necrosis or bile duct loss at the time of diagnosis of LAR were associated with high risk of progression to chronic rejection and graft loss.

Adolescent↗
PubMed1995

Sex mismatch as a risk factor for chronic rejection of liver allografts.

Chronic irreversible rejection is a major cause of graft loss and retransplantation after orthotopic liver allotransplantation. To identify risk factors we retrospectively analysed 423 adult consecutive primary liver allograft recipients. The endpoint of the study was graft failure due to chronic rejection leading either to retransplantation or death. Chronic rejection developed in 22 (5.2%) patients. Pretransplant diagnosis of primary biliary cirrhosis or autoimmune hepatitis, recipient age less than 30 years, 1 or more episodes of acute cellular rejection, and transplantation of an organ from cytomegalovirus (CMV). IgG positive donor to an IgG negative recipient were identified as risk factors for chronic rejection. Transplantation of a liver from a male donor into a female recipient was also associated with an increased probability of chronic rejection. By logistic regression analysis, the probability of chronic rejection was predicted by: sex and cytomegalovirus match of donor and recipient, the presence of acute rejection, recipient age, transplantation for autoimmune hepatitis or primary biliary cirrhosis, and recipients receiving no azathioprine during the third month after transplantation. Sensitisation to antigens expressed by bile-duct epithelium as in primary biliary cirrhosis or exposure to donor bile-duct minor histocompatibility antigens, such as the male sex related H-Y antigen, may provide an explanation. More selective allocation of donor organs may allow a reduction in the incidence of ductopaenic rejection and graft loss.

ABO Blood-Group System↗
PubMed1995

Apoptosis in the human liver during allograft rejection and end-stage liver disease.

The contribution of apoptosis (programmed cell death) to cellular damage in human liver disease is unknown. Using the in situ DNA end labelling method (ISEL), evidence was sought of programmed cell death (PCD) in liver tissue from patients with various liver diseases. In particular, the study aimed to determine whether PCD is involved in either the loss of interlobular bile ducts (vanishing bile duct syndrome--VBDS) or the perivenular hepatocyte drop-out, both of which are characteristic of irreversible graft rejection. Large numbers of apoptotic hepatocytes were found in perivenular areas in tissues taken from patients with chronic graft rejection. Significant hepatocyte apoptosis, was not seen in long-term stable allografts, primary biliary cirrhosis, cholestasis, paracetamol-induced fulminant hepatic failure, or fulminant hepatic failure of indeterminate origin (non-A, non-B, non-C hepatitis). Bile ducts rarely stained positively, but mononuclear cells present in the post-transplant tissues were frequently positive, showing nuclear or cytoplasmic staining. The presence of cytoplasmic staining suggested that some mononuclear cells had ingested apoptotic DNA from other cellular sources. PCD may thus contribute to the perivenular hepatocyte loss in chronic rejection. The absence of ductular epithelial cell staining suggests that PCD is not involved significantly in the bile duct loss of VBDS. Furthermore, apoptosis of mononuclear cells implies that PCD may be involved in regulating the inflammatory cell infiltration of graft rejection.

Apoptosis↗
PubMed1995

Subcellular localization of pyruvate dehydrogenase dihydrolipoamide acetyltransferase in human intrahepatic biliary epithelial cells.

In previous histological studies, biliary epithelial cells (BEC) in the liver of patients with primary biliary cirrhosis (PBC), but not controls, reacted strongly with antibodies specific for the major autoantigen associated with PBC, the E2 component of pyruvate dehydrogenase complex (PDC-E2). In this study we have used transmission electron microscopy (TEM) to document the precise subcellular localization of PDC-E2 in BEC. Two antibodies which recognize PDC-E2 were used: affinity-purified anti-PDC-E2 raised in rabbits; and human antibody from the serum of patients with PBC, affinity-purified against human heart PDC. The intracellular localization of antibody binding was determined by laser scanning confocal microscopy and TEM. Both antibodies bound to the inner membrane of mitochondria in BEC isolated from both patients with PBC and controls, but binding to the external aspect of the plasma membrane was observed only in BEC from patients with PBC. Surface antigen expression in PBC may make BEC immunological targets.

Adult↗
PubMed1995

Hepatitis C virus infection in the asymptomatic British blood donor.

Blood donor screening for hepatitis C virus (HCV) antibodies is now routine. Most blood transfusion services recommend that seropositive donors are referred for further investigation. Southern European studies suggest that many asymptomatic seropositive donors have clinically significant liver disease. Seropositive donors in areas of high prevalence may not, however, be representative of British donors. We have prospectively examined the prevalence and severity of HCV infection in a British volunteer blood donor population. During a 14 month period, only 0.35% (999/287,332) of all donors in the West Midlands were anti-HCV (screening assay) positive. Only 5% (52/999) of these were confirmed true seropositive. Nearly 80% (41/52) of seropositive donors were referred to the Queen Elizabeth Hospital Liver Unit for further investigation. Most underwent complete investigation, including liver biopsy. Forty of forty-one donors had biochemical, histological, or virological evidence of persistent viral infection. Histological changes were generally mild and none was cirrhotic. Covertly infected patients had less severe disease than those with an overt risk factor for HCV exposure. In the British Midlands, the prevalence of blood donor seropositivity is low. In contrast with seropositive Southern European donors, the British donor is more likely to belong to an at-risk group for parenteral exposure and is less likely to have severe histological changes. This study highlights the importance of developing locally relevant guidelines for the counselling and investigation of anti-HCV-positive blood donors.

Adult↗
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↗