16 research outputs found

    ALLOREACTIVE T LYMPHOCYTES CULTURED FROM LIVER TRANSPLANT BIOPSIES: ASSOCIATIONS OF HLA SPECIFICITY WITH CLINICOPATHOLOGICAL FINDINGS.

    Get PDF
    Lymphocyte cultures grown from liver allograft biopsies were shown to exhibit alloreactivity towards donor cells as measured by primed lymphocyte testing (PLT). The PLT specificity was determined in assays using HLA typed panel cells and/or by inhibition testing with HLA specific monoclonal antibodies. Certain cultures exhibited PLT specificity towards class I HLA antigens of the donor, whereas others were specific for class II HLA antigens or recognized mixtures of class I and II antigens. These PLT specificity patterns were compared with clinical, histological and laboratory findings on the liver transplant patients at the time of the biopsy. Biopsies yielding class I specific PLT cells were taken generally during the earlier posttransplant period, whereas class II specific cells were grown from later biopsies. There was no significant correlation of the PLT specificity towards class I vs II antigens with the levels of total or direct bilirubin, serum glutamate oxaloacetic transaminase (SGOT), and serum glutamate pyruvate transaminase (SGPT), although a trend towards higher values was noted for biopsies presenting with a class II specific infiltrate. However, the levels of gamma glutamyl transpeptidase (GGTP) and alkaline phosphatase (AP) were significantly increased when biopsies yielded class II specific rather than class I specific PLT cells. Biopsy histology showed more damage to bile duct epithelium in association with class II PLT specificity whereas intense but often reversible infiltrates were found in biopsies yielding class I specific cells. The elevated GGTP and AP levels are probably related to the interaction of class II specific T cells with bile duct epithelium, which has been shown to express induced class II HLA antigens on their cell surface

    Allografts Surviving for 26 to 29 Years Following Living-Related Kidney Transplantation: Analysis by Light Microscopy, In Situ Hybridization for the Y Chromosome, and Anti-HLA Antibodies

    Get PDF
    We studied seven patients aged 14 to 40 years who received living-related kidney transplants and had allograft survivals of 26 to 29 years. The blood urea and creatinine were either within normal limits or marginally elevated. Histopathologic examination showed only mild mesangial expansion, interstitial fibrosis, and arteriosclerosis. Immunoperoxidase staining with anti-HLA antibodies or in situ hybridization with a Y chromosome probe showed persistence of donor tubular epithelium and vascular endothelium within the graft. Recipient-derived glomerular cells were seen in one case, and interstitial lymphocytic infiltrates were seen in all cases. A review of the clinicopathologic data available for these cases indicated that both central and peripheral immunologic mechanisms contributed to the maintenance of prolonged graft survival. This extended survival was independent of six antigen matching, downregulation of donor HLA antigen expression, and ingrowth of host epithelium/endothelium into the allograft. © 1994, National Kidney Foundation. All rights reserved. All rights reserved

    A new liver perfusion and preservation system for transplantation Research in large animals

    Get PDF
    A kidney perfusion machine, model MOX-100 (Waters Instruments, Ltd, Rochester, MN) was modified to allow continuous perfusion of the portal vein and pulsatile perfusion of the hepatic artery of the liver. Additional apparatus consists of a cooling system, a membrane oxygenator, a filter for foreign bodies, and bubble traps. This system not only allows hypothermic perfusion preservation of the liver graft, but furthermore enables investigation of ex vivo simulation of various circulatory circumstances in which physiological perfusion of the liver is studied. We have used this system to evaluate the viability of liver allografts preserved by cold storage. The liver was placed on the perfusion system and perfused with blood with a hematocrit of approximately 20% and maintained at 37°C for 3 h. The flows of the hepatic artery and portal vein were adjusted to 0.33 mL and 0.67 mL/g of liver tissue, respectively. Parameters of viability consisted of hourly bile output, oxygen consumption, liver enzymes, electrolytes, vascular resistance, and liver histology. This method of liver assessment in large animals will allow the objective evaluation of organ viability for transplantation and thereby improve the outcome of organ transplantation. Furthermore, this pump enables investigation into the pathophysiology of liver ischemia and preservation. © 1990 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted

    Occurrence of cytomegalovirus hepatitis in liver transplant patients

    Get PDF
    The differential diagnosis of liver dysfunction after orthotopic liver transplantation can be difficult. Cytomegalovirus (CMV) hepatitis is one possibility. This report reviews our experience with 17 cases of pathologically proven CMV hepatitis following liver transplantation and demonstrates the need for percutaneous liver biopsies to establish the diagnosis. There were seven pediatric patients (ages 2–11 years, five males, two females) and ten adult patients (ages 17–53 years, eight males, two females). The most common symptoms were prolonged fever (15 patients, with a mean duration of 22 ± 5.5 days), elevation in total bilirubin (14 patients), and elevation in liver enzymes (15 patients); all symptoms were also found in rejection. Leukopenia and thrombocytopenia, reported to frequently occur with CMV infection, were found in only three and five patients, respectively. Twelve patients with the above symptoms underwent percutaneous biopsy on one or more occasions to differentiate CMV hepatitis from rejection. The diagnosis was made at retransplantation in five patients. CMV hepatitis followed treatment for acute rejection in 14 patients and occurred without additional immunosuppression in three patients. All patients were maintained on cyclosporine and prednisone. Acute rejection episodes were treated with a 5‐day tapering dose of steroids (17 courses in 12 patients), OKT3 monoclonal antibody [Ortho (4 patients)] antithymocyte globulin [Upjohn (2 patients)], and azathioprine (1 patient). CMV was isolated from urine (nine patients), blood (nine patients), throat (seven patients), lungs (two patients), and other organs (two patients). CMV was cultured from the liver biopsy specimens in five of the seven attempts in pediatric patients. When the diangosis was confirmed in the absence of rejection, immunosuppression was routinely lowered. When rejection occurred concomitantly with CMV hepatitis, therapy had to be individualized. Retrospectively, three patients treated for rejection were noted at retransplantation to have only CMV hepatitis, and all three paients died. A high index of suspicion and the judicioususe of liver bopsies is essential in order to differentiate CMV hepatitis from other causes of posttransplant liver dysfunction. Copyright © 1988 Wiley‐Liss, Inc., A Wiley Compan

    Effect of liver transplantation on inflammatory bowel disease in patients with primary sclerosing cholangitis

    Get PDF
    This report investigates the influence of liver transplantation and concomitant immunosuppression on the course of progression of inflammatory bowel disease (IBD) and discusses statistical methodology appropriate for such settings. The data on 303 patients who underwent liver transplantation for primary sclerosing cholangitis (PSC) were analyzed using person-time analysis and Cox regression, with the duration of IBD as the time variable and transplantation as a segmented time-dependent covariate, to take into account both posttransplant and pretransplant history of IBD. The need for colectomy and appearance of colorectal cancer were taken as outcome measures. The only significant risk factor in the multivariate model for colectomy was transplantation itself, which increased the risk of colectomy due to intractable disease (Wald statistic; P =. 001). None of the variables available for analysis were found to influence the risk of colon cancer significantly. Graphs showing the dependence of the instantaneous risk of cancer on the time from onset of IBD and its independence from the latter in the case of colectomy are presented. The use of a unique statistical methodology described for the first time in this setting led us to the somewhat surprising conclusion that transplantation and concomitant use of immunosuppression accelerate the progression of IBD. At the same time, transplantation does not affect the incidence of colorectal cancer. These results confirm the findings of some recent studies and can potentially shed new light on the disease pathogenesis

    Banff consensus recommendations for steatosis assessment in donor livers.

    No full text
    No consensus criteria or approach exist regarding assessment of steatosis in the setting of human donor liver suitability for transplantation. The Banff Working Group on Liver Allograft Pathology undertook a study to determine the consistency with which steatosis is assessed and reported in frozen sections of potential donor livers. A panel of 59 pathologists from 16 countries completed a questionnaire covering criteria used to assess steatosis in donor liver biopsies, including droplet size and magnification used; subsequently, steatosis severity was assessed in 18 whole slide images of donor liver frozen sections (n=59). Survey results (from 56/59) indicated a wide variation in definitions and approaches used to assess and report steatosis. Whole slide image assessment led to a broad range in the scores. Findings were discussed at a workshop held at the 15 Banff Conference on Allograft Pathology, September 2019. The aims of discussions were to (i) establish consensus criteria for defining "large droplet fat" (LDF) that predisposes to increased risk of initial poor graft function; and (ii) develop an algorithmic approach to determine fat droplet size, and the percentage of hepatocytes involved. Large droplet fat was defined as typically a single fat droplet that expands the involved hepatocyte and is larger than adjacent non-steatotic hepatocytes. Estimating severity of steatosis involves (i) low magnification estimate of the approximate surface area of the biopsy occupied by fat, (ii) higher magnification determination of the percentage of hepatocytes within the fatty area with large droplet fat and (iii) final score calculation. The proposed guidelines herein are intended to improve standardization in steatosis assessment of donor liver biopsies. The calculated percent LDF should be provided to the surgeon

    Fibrosis correlates with a ductular reaction in hepatitis C: Roles of impaired replication, progenitor cells and steatosis

    No full text
    The mechanisms for progressive fibrosis and exacerbation by steatosis in patients with chronic hepatitis C (HCV) are still unknown. We hypothesized that proliferative blockade in HCV-infected and steatotic hepatocytes results in the default activation of hepatic progenitor cells (HPC), capable of differentiating into both biliary and hepatocyte lineages, and that the resultant ductular reaction promotes portal fibrosis. To study this concept, 115 liver biopsy specimens from subjects with HCV were scored for steatosis, inflammation, and fibrosis. Biliary epithelium and HPC were decorated by cytokeratin 7 immunoperoxidase, and the replicative state of hepatocytes was assessed by p21 and Ki-67 immunohistochemistry. A ductular reaction at the portal interface was common. There was a highly significant correlation between the area of ductular reaction and fibrosis stage (r = 0.453, P < .0001), which remained independently associated after multivariate analysis. HPC numbers also correlated with fibrosis (r = 0.544, P < .0001) and the ductular area (r = 0.624, P < .0001). Moreover, steatosis correlated with greater HPC proliferation (r = 0.372, P = .0004) and ductular reaction (r = 0.374, P < .0001) but was not an obligate feature. Impaired hepatocyte replication by p21 expression was independently associated with HPC expansion (P = .002) and increased with the body mass index (P < .001) and lobular inflammation (P = .005). In conclusion, the strong correlation between portal fibrosis and a periportal ductular reaction with HPC expansion, the exacerbation by steatosis, and the associations with impaired hepatocyte replication suggest that an altered regeneration pathway drives the ductular reaction. We believe this triggers fibrosis at the portal tract interface. This may be a stereotyped response of importance in other chronic liver diseases
    corecore