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Susanne Beckebaum

Publications and source records attributed to Susanne Beckebaum.

14 recordsLinked to original sources
PubMed2006

Cyclosporine versus tacrolimus in patients with HCV infection after liver transplantation: effects on virus replication and recurrent hepatitis.

AIM: To determine the effects of the calcineurin inhibitors, cyclosporine and tacrolimus, on hepatitis C virus (HCV) replication and activity of recurrent hepatitis C in patients post liver transplantation. METHODS: The data of a cohort of 107 patients who received liver transplantation for HCV-associated liver cirrhosis between 1999 and 2003 in our center were retrospectively analyzed. The level of serum HCV-RNA and the activity of recurrent hepatitis were compared between 47 patients who received either cyclosporine or tacrolimus as the primary immunosuppressive agent and an otherwise similar immunosuppressive regimen which did not lead to biliary complications within the first 12 mo after transplantation. RESULTS: HCV-RNA increased within 3 mo after transplantation but the differences between the cyclosporine group and the tacrolimus group were insignificant (P=0.49 at 12 mo). In addition, recurrent hepatitis as determined by serum transaminases and histological grading of portal inflammation and fibrosis showed no significant difference after 12 mo (P=0.34). CONCLUSION: Cyclosporine or tacrolimus as a primary immunosuppressive agent does not influence the induction or severity of recurrent hepatitis in HCV-infected patients after liver transplantation.

Adult↗
PubMed2006

Living donor liver transplantation for hepatocellular carcinoma: a single-center preliminary report.

Liver transplantation (LT) is the treatment of choice for early hepatocellular carcinoma (HCC) in patients with end-stage liver disease but is limited by the availability of donor organs. Living donor liver transplantation (LDLT) represents an alternative therapeutic option for patients with disease confined to the liver. Between April 1998 and December 2003, 537 patients underwent liver transplantation in our center. Thirty patients with HCC and associated terminal cirrhosis and 4 patients with tumor recurrence after liver resection who underwent LDLT were reviewed. Nineteen patients (55.8%) met the Milan criteria for LT, whereas 15 patients (44.2%) "exceeded" them. The overall survival rates at 1 and 2 years were 68% and 62%, respectively, with a median follow-up of 41 months (range, 17-64 months). Five patients (14.7%) died in the first 30 days after LDLT. Hospital mortality was significantly correlated with age > 60 years. Four patients developed recurrence between 6 and 35 months after LDLT. Recurrence was significantly related to the presence of more than 3 tumor lesions in our series. In conclusion, LDLT is a promising treatment option for patients with HCC. Even longer follow-up and bigger patients' series are needed to fully assess the benefits of LDLT for HCC patients exceeding the Milan criteria.

Adolescent↗
PubMed2005

Impact of p53-based immunization on primary chemically-induced tumors.

In mice as well as humans, cytotoxic T lymphocytes (CTL) specific for wild-type-sequence (wt) p53 peptides have been shown to react against a wide range of tumors, but not normal cells. As such, they are attractive candidates for developing broadly applicable cancer vaccines. Of particular interest is the potential of using p53-based vaccines in high-risk individuals to prevent cancer. Methylcholanthrene, an immunosuppressive polycyclic hydrocarbon carcinogen implicated as a causative agent in human cancers, has long been used to induce murine tumors with a high incidence of genetic alterations and sensitivity to wt p53-specific CTL. To analyze the potential of p53-based vaccines on primary tumors, we evaluated the efficacy of DNA and dendritic cell vaccines targeting wt p53 peptides given to methylcholanthrene-treated mice in the protection or therapy settings. The results indicate that the efficacy of these vaccines relative to reducing tumor incidence were severely compromised by vaccine-induced tumor escape. As compared to tumors induced in non-immunized mice, a higher incidence of epitope-loss tumors was detected in tumors from the immunized mice. The increase in tumor escape arose as a consequence of either increased frequencies of mutations within/flanking p53 epitope-coding regions or downregulation of expression of the major histocompatibility complex Class I molecules that present these epitopes for T cell recognition These findings are consistent with current views of immunoselection occurring in patients receiving tumor peptide-based immunotherapy, and impact on the design and implementation of p53-based vaccines, in particular, those aimed at treating individuals at high risk for developing cancer.

Adenoviridae↗
PubMed2005

Effectiveness of a new carrier-bound fibrin sealant versus argon beamer as haemostatic agent during liver resection: a randomised prospective trial.

BACKGROUND AND AIMS: A new carrier-bound fibrin sealant, TachoSil, is expected to be efficacious and safe as a haemostatic treatment in hepatic resection. DESIGN: A prospective, randomised, open and controlled multicentre trial with intraoperative as well as postoperative assessment of efficacy and a 1 month follow-up period. SETTING: Tertiary care centres. PATIENTS/METHODS: One hundred and twenty-one patients requiring secondary haemostasis during planned liver resection. Patients with coagulation disorders and patients with persistent major bleeding after primary haemostatic measures were excluded. INTERVENTION: Application of either carrier-bound fibrin sealant (n=59) or argon beamer (argon beam coagulator) (n=62) as secondary haemostatic treatment. MAIN OUTCOME MEASURE: Time to intraoperative haemostasis. RESULTS: There was a significant superiority of TachoSil over argon beamer with regard to time to haemostasis (3.9 min, median 3.0, range 3-20 min vs 6.3 min, median 4.0, range 3-39 min) (P=0.0007). Haemoglobin concentration of drainage fluid was significantly lower on day 2 after surgery in TachoSil patients (1.1 mmol/l) than in argon beamer patients (2.3 mmol/l) (P=0.012). Overall, the frequency and causality of adverse events did not differ between the two treatment groups. CONCLUSION: TachoSil is superior to argon beamer in obtaining effective and fast intraoperative haemostasis. The safety data show TachoSil to be tolerable and safe for haemostatic treatment in liver resection.

Drug Carriers↗
PubMed2005

Unpulsed dendritic cells induce broadly applicable anti-tumor immunity in mice.

The discovery of dendritic cells (DC) as professional antigen presenting cells has opened up new possibilities for their use in the development of cancer vaccines. Here we show that unpulsed BM-derived CD11c+CD8alpha-DC administered s.c. to mice enhanced their resistance to subsequent lethal tumor challenges. The tumor resistance-inducing activity of unpulsed DC was dependent on their maturation status, involved CD4+ and CD8+ T cell activities, and was abrogated by pulsing with an irrelevant class I MHC-restricted peptide. Although the BALB/c Meth A tumor system was employed extensively to demonstrate the tumor resistance inducing activity of unpulsed DC, the immunogenicity of this vaccine was evident in other inbred strains of mice against a variety of syngeneic tumors. The broad anti-tumor responses induced by unpulsed DC appears to be due to their capacity to present "self" tumor-associated antigens, such as the H2-Kd-restricted, wild type sequence p53(232-240) peptide. These findings highlight the potential broad applicability of unpulsed DC as a tumor vaccine.

Animals↗
PubMed2004

Increased levels of interleukin-10 in serum from patients with hepatocellular carcinoma correlate with profound numerical deficiencies and immature phenotype of circulating dendritic cell subsets.

Increased levels of interleukin (IL)-10 have been described as a negative prognostic indicator for survival in patients with various types of cancer. IL-10 exerts tolerogenic and immunosuppressive effects on dendritic cells, which are crucial for the induction of an antitumor immune response. Blood dendritic cell antigen (BDCA)-2 and BDCA-4 are specifically expressed by CD123(bright) CD11c- plasmacytoid dendritic cells; whereas BDCA-1 and BDCA-3 define 2 distinct subsets of CD11c+ myeloid dendritic cells. In this study, the T-helper cell (Th)1/Th2 cytokine serum profile of 65 hepatocellular carcinoma patients was assessed. We found that serum levels of IL-10 were substantially increased in hepatocellular carcinoma patients as compared with controls. Peripheral blood mononuclear cells from healthy volunteers were exposed to recombinant human (rh)IL-10 in vitro to additionally characterize its impact on distinct blood dendritic cell subsets. A dramatic decrease of all myeloid dendritic cell (MDC) and plasmacytoid dendritic cell (PDC) subsets was detectable after 24 hours of continuous rhIL-10 exposure. Moreover, the expression of HLA-DR, CD80 and CD86, was significantly reduced on rhIL-10-treated dendritic cell subsets. Direct ex vivo flow cytometric analysis of various dendritic cell subpopulations in peripheral blood from hepatocellular carcinoma patients revealed an immature phenotype and a substantial reduction of circulating dendritic cells that was associated with increased IL-10 concentrations in serum and with tumor progression. These findings confirm a predominantly immunosuppressive role of IL-10 for circulating dendritic cells in patients with hepatocellular carcinoma and, thus, may indicate novel aspects of tumor immune evasion.

Adult↗
PubMed2004

Molecular profiling of human hepatocellular carcinoma defines mutually exclusive interferon regulation and insulin-like growth factor II overexpression.

Molecular subtyping of human hepatocellular carcinoma (HCC) with potential mechanistic and therapeutic impact has not been achieved thus far. We have analyzed the mRNA expression patterns of 43 different human HCC samples and 3 HCC cell lines in comparison with normal adult liver using high-density cDNA microarrays. Two main groups of HCC, designated group A (65%) and group B (35%), were distinguished based on clustering of the most highly varying genes. Group A HCCs were characterized by induction of a number of interferon (IFN)-regulated genes, whereas group B was characterized mainly by down-regulation of several apoptosis-relevant and IFN-regulated genes. The number of apoptotic tumor cells and tumor-infiltrating lymphocytes was significantly higher in tumors of group A as compared with those of group B. Based on the expression pattern, group B was further subdivided into two subgroups, designated subgroup B1 (6 of 43 tumors, 14%) and subgroup B2 (9 of 43 tumors, 21%). A prominent characteristic of subgroup B1 was high overexpression of insulin-like growth factor (IGF)-II. All tested HCC cell lines expressed equally high concentrations of IGF-II transcripts and co-segregated with group B1 in clustering. IGF-II overexpression and induction of IFN-related genes were mutually exclusive, even when analysis was extended to other cancer expression profile studies. Moreover, IFN-gamma treatment substantially reduced IGF-II expression in HCC cells. In conclusion, cDNA microarray analyses provided subtyping of HCCs that is related to intratumor inflammation and tumor cell apoptosis. This profiling may be of mechanistic and therapeutic impact because IGF-II overexpression has been linked to reduced apoptosis and increased proliferation and may be accessible to therapeutic intervention.

Carcinoma, Hepatocellular↗
PubMed2004

Latest development in split liver transplantation.

Currently, orthotopic liver transplantation (LT) represents the treatment of choice for most end-stage liver diseases. Advances in surgical techniques and immunosuppressive therapy have markedly increased its success. However, the main obstacle in LT remains the lack of donor organs with a current mortality rate for patients on the waiting list of up to 20%. This chapter focuses on developments in SLT techniques and living-donor LT to alleviate this problem. SLT yields a net gain of organs, in that it uses one organ to save either an adult and a child, or two adults. The initially used technique of ex-situ splitting is being replaced progressively by the in-situ splitting technique, which yields better preserved grafts. The latest step has been the introduction of living-donor segmental LT. The systematic combination of both techniques may lead to a further reduction of mortality for patients on the waiting list for LT.

Female↗
PubMed2003

Efficacy of combined lamivudine and adefovir dipivoxil treatment for severe HBV graft reinfection after living donor liver transplantation.

Resistance to lamivudine and hyperimmune globulin (HBIG) may cause severe graft reinfection with progression to fulminant hepatic failure in liver transplant recipients. In this report, we describe the clinical course of a patient with perinatally acquired chronic hepatitis B virus (HBV) infection and hepatocellular carcinoma who developed severe fibrosing cholestatic hepatitis after living donor liver transplantation because of the emergence of lamivudine and HBIG-resistant chronic hepatitis B. Immunohistochemistry demonstrated that more than 30% of hepatocytes stained positively for hepatitis B core antigen. Hepatitis B virus sequence analysis revealed several mutations in the polymerase gene (L528M, M552I, M552V) as well as in the surface gene region encoding the immunogenic major hydrophilic loop of the small surface protein (G130N, M133T, D144G). The amino acid exchange at codon 144 has already been described to escape neutralization by HBIG. Combined treatment with lamivudine and adefovir dipivoxil (ADV) was associated with a dramatic biochemical, virological and clinical response with resolution of jaundice, ascites, peripheral edema and pleural effusions. Serum bilirubin normalized, HBV DNA levels significantly decreased and liver biopsy was remarkable for the absence of viral protein. These results indicate that ADV may provide a sustained rescue treatment for aggressive courses of HBV graft reinfection in liver transplant recipients.

Adenine↗
PubMed2003

Hepatitis B virus-induced defect of monocyte-derived dendritic cells leads to impaired T helper type 1 response in vitro: mechanisms for viral immune escape.

Dendritic cells (DC) are the most potent antigen-presenting cells and play a central role in the induction of antiviral immune responses. Recently, we have shown that monocyte-derived DC (MoDC) from patients with chronic hepatitis B virus (HBV) infection are functionally impaired. In our present study MoDC from healthy subjects were propagated in vitro and inoculated with HBV particles to investigate the precise mechanisms that underly MoDC dysfunction. T-cell proliferation assays revealed an impaired allostimulatory capacity of HBV-inoculated MoDC (HBV-MoDC) as well as a lower potential of stimulating autologous T cells against a recall antigen in comparison to control-MoDC. Interleukin-2, tumour necrosis factor-alpha and interferon-gamma production by T cells in proliferation assays with HBV-MoDC was significantly lower than with control-MoDC and correlated with lower IL-12 production in HBV-MoDC cultures. The presence of the nucleoside analogue lamivudine (3TC), an inhibitor of HBV replication, restored impaired allostimulatory function of HBV-MoDC and up-regulated major histocompatibility complex class II expression. These results show that HBV infection compromises the antigen-presenting function of MoDC with concomitant impairment of T helper cell type 1 responses. This may play an important role for viral immune escape leading to chronic HBV infection. However, 3TC treatment can overcome HBV-MoDC-related T-cell hyporeactivity and this underscores its important role in enhanced immune responses to HBV.

Adult↗
PubMed2002

Reduction in the circulating pDC1/pDC2 ratio and impaired function of ex vivo-generated DC1 in chronic hepatitis B infection.

Dendritic cells (DCs) induce and regulate T-cell-mediated immune responses. Circulating precursor (p)DC1 and pDC2 from patients with chronic hepatitis B virus (HBV) infection were quantified by flow cytometry. To assess their function, DC1 were cultured from patients and compared to those of healthy volunteers. HBV patients exhibited a significant decrease in the proportion of freshly isolated pDC1 to pDC2. DC1 propagated from patients showed lower expression of costimulatory molecules and impaired allostimulatory capacity in comparison to controls. After exposure to proinflammatory cytokines, expression of costimulatory molecules, secretion of interleukin-12 (IL-12) and allostimulatory properties increased, but capacity for T-cell stimulation and IL-12 production remained inferior to that of control DCs. HBV-DNA was amplified by polymerase chain reaction in DC1 cultured from all patients. Viral particles were visible in DC1 by electron microscopy. These results suggest that intracellular presence of HBV impairs DC1 functional maturation and subsequent deficits in T-lymphocyte activation may contribute to viral persistence.

Cell Division↗
PubMedDate not supplied

DNA-based immunotherapy: potential for treatment of chronic viral hepatitis?

Persistent HBV and HCV infection represent major causes of chronic liver disease with a high risk of progression to liver cirrhosis and hepatocellular carcinoma (HCC). Conventional protein-based vaccines are highly efficacious in preventing HBV infection; whereas in therapeutic settings with chronically infected patients, results have been disappointing. Prophylactic vaccination against HCV infection has not yet been achieved due to many impediments including frequent spontaneous mutations of the virus with escape from immune system control. Using animal models it has been demonstrated that DNA-based immunisation strategies may overcome this problem because of their potential to induce immunity against multiple viral epitopes. DNA-based vaccines mimic the effect of live attenuated viral vaccines, eliciting cell mediated immunity in addition to inducing humoral responses. Efficacy may further be improved by addition of DNA encoding immunomodulatory cytokines and more recently, direct genetic modulation of antigen-presenting cells, such as dendritic cells (DC), has been shown to increase antigen-specific immune responses. This review focuses on immunological aspects of chronic HBV and HCV infection and on the potential of DNA- and DC-based vaccines for the treatment of chronic viral hepatitis.

Animals↗
PubMedDate not supplied

Major bile duct injuries after laparoscopic cholecystectomy: a tertiary center experience.

Bile duct injury is a severe and potentially life-threatening complication of laparoscopic cholecystectomy. Several series have described a 0.5% to 1.4% incidence of bile duct injuries during laparoscopic cholecystectomy. The aim of this study was to report on an institutional experience with the management of complex bile duct injuries and outcome after surgical repair. Data were collected prospectively from 40 patients with bile duct injuries referred for surgical treatment to our center between April 1998 and December 2003. Prior to referral, 35 patients (87.5%) underwent attempts at surgical reconstruction at the primary hospital. In 77.5% of the patients, complex type E1 or type E2 BDI was found. Concomitant with bile duct injury, seven patients had vascular injuries. Roux-en-Y hepaticojejunostomy was carried out in 33 patients. In two patients, Roux-en-Y hepaticojejunostomy and vascular reconstruction were necessary. Five patients, one with primary nondiagnosed Klatskin tumor, required right hepatectomy. Two patients, both with bile duct injuries and vascular damage, died postoperatively. Because of progressive liver insufficiency, one of them was listed for high-urgency liver transplantation but died prior to intervention. At the median follow-up of 589 days, 82.5% of the patients are in excellent general condition. Seven patients have signs of chronic cholangitis. Major bile duct injuries remain a significant cause of morbidity and even death after laparoscopic cholecystectomy. Because they present a considerable surgical challenge, early referral to an experienced hepatobiliary center is recommended.

Adult↗