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Featured researches published by J. Klempnauer.


The FASEB Journal | 2002

Hepatocyte telomere shortening and senescence are general markers of human liver cirrhosis

Stefanie Wiemann; Ande Satyanarayana; Martina Tsahuridu; Hans L. Tillmann; Lars Zender; J. Klempnauer; Peer Flemming; Sonia Franco; Maria A. Blasco; Michael P. Manns; K. Lenhard Rudolph

Telomere shortening limits the number of cell divisions of primary human cells and might affect the regenerative capacity of organ systems during aging and chronic disease. To test whether the telomere hypothesis applies to human cirrhosis, the telomere length was monitored in cirrhosis induced by a broad variety of different etiologies. Telomeres were significantly shorter in cirrhosis compared with noncirrhotic samples independent of the primary etiology and independent of the age of the patients. Quantitative fluorescence in situ hybridization showed that telomere shortening was restricted to hepatocytes whereas lym‐phocytes and stellate cells in areas of fibrosis had significantly longer telomere reserves. Hepatocyte‐specific telomere shortening correlated with senescence‐associated p‐galactosidase staining in 84% of the cirrhosis samples, specifically in hepatocytes, but not in stellate cells or lymphocytes. Hepatocyte telomere shortening and senescence correlated with progression of fibrosis in cirrhosis samples. This study demonstrates for the first time that cell type‐specific telomere shortening and senescence are linked to progression of human cirrhosis. These findings give a novel explanation for the pathophysiology of cirrhosis, indicating that fibrotic scarring at the cirrhosis stage is a consequence of hepatocyte telomere shortening and senescence. The data imply that future therapies aiming to restore regenerative capacity during aging and chronic diseases will have to ensure efficient targeting of specific cell types within the affected organs.—Wiemann, S. U., Satyanarayana, A., Tsahuridu, M., Tillmann, H. L., Zender, L., Klempnauer, J., Flemming, P., Franco, S., Blasco, M. A., Manns, M. P., Rudolph, K. L. Hepatocyte telomere shortening and senescence are general markers of human liver cirrhosis. FASEB J. 16, 935–942 (2002)


Liver Transplantation | 2010

Hepatitis E virus infection as a cause of graft hepatitis in liver transplant recipients

Sven Pischke; P.V. Suneetha; Christine Baechlein; Hannelore Barg-Hock; Albert Heim; Nassim Kamar; Jerome Schlue; Christian P. Strassburg; Frank Lehner; R. Raupach; B. Bremer; Peter Magerstedt; Markus Cornberg; Frauke Seehusen; Wolfgang Baumgaertner; J. Klempnauer; Jacques Izopet; Michael P. Manns; Beatrice Grummer; Heiner Wedemeyer

Hepatitis E virus (HEV) infection induces self‐limiting liver disease in immunocompetent individuals. Cases of chronic hepatitis E have recently been identified in organ transplant recipients. We questioned if chronic hepatitis E plays a role in graft hepatitis after liver transplantation in a low endemic area. Two hundred twenty‐six liver transplant recipients, 129 nontransplanted patients with chronic liver disease, and 108 healthy controls were tested for HEV antibodies. HEV RNA was investigated in all sera from transplanted patients. HEV antibodies were detected in 1 healthy control (1%), 4 patients with chronic liver disease (3%), and 10 liver transplant recipients (4%). Three liver transplant patients also tested positive for HEV RNA. Two of them developed persistent viremia with HEV genotype 3. The patients were anti‐HEV immunoglobulin G–negative and HEV RNA–negative before transplantation and had an episode of acute hepatitis 5 or 7 months after transplantation, which led to advanced liver fibrosis after 22 months in 1 patient. Seroconversion to anti‐HEV occurred not before 4 months after the first detection of HEV RNA. The possibility of reverse zoonotic transmission was experimentally confirmed by the infection of 5 pigs with a patients serum. The pigs showed histological inflammation in the liver, and HEV RNA was detectable in different organs, including muscle. In conclusion, the prevalence of HEV infection in Central European liver transplant recipients is low; however, chronic hepatitis E may occur and needs to be considered in the differential diagnosis of graft hepatitis. The diagnosis of HEV infection should be based on HEV RNA determination in immunosuppressed patients. We suggest that immunocompromised individuals should avoid eating uncooked meat and contact with possibly HEV‐infected animals. Liver Transpl 16:74–82, 2010.


Clinical Transplantation | 2004

Long-term outcome of liver transplantation for autoimmune hepatitis

Arndt Vogel; Eyk Heinrich; Matthias J. Bahr; Kinan Rifai; Peer Flemming; Michael Melter; J. Klempnauer; Björn Nashan; Michael P. Manns; Christian P. Strassburg

Abstract:  Background:  Liver transplantation is the final therapeutic option for about 10% of patients with autoimmune hepatitis (AIH) who do not respond to medical therapy. The aim of this study was to evaluate the long‐term outcome in serologically defined subgroups of AIH after transplantation.


American Journal of Transplantation | 2012

A Randomized, Controlled Study to Assess the Conversion From Calcineurin-Inhibitors to Everolimus After Liver Transplantation—PROTECT

Lutz Fischer; J. Klempnauer; Susanne Beckebaum; Herold J. Metselaar; Peter Neuhaus; Peter Schemmer; U. Settmacher; Nils Heyne; P.‐A. Clavien; Ferdinand Muehlbacher; Isabelle Morard; H. Wolters; Wolfgang Vogel; Tim Becker; Martina Sterneck; Frank Lehner; Christoph Klein; Geert Kazemier; Andreas Pascher; Jan Schmidt; Falk Rauchfuss; Andreas A. Schnitzbauer; Silvio Nadalin; M. Hack; Stephan Ladenburger; Hans J. Schlitt

Posttransplant immunosuppression with calcineurin inhibitors (CNIs) is associated with impaired renal function, while mTor inhibitors such as everolimus may provide a renal‐sparing alternative. In this randomized 1‐year study in patients with liver transplantation (LTx), we sought to assess the effects of everolimus on glomerular filtration rate (GFR) after conversion from CNIs compared to continued CNI treatment. Eligible study patients received basiliximab induction, CNI with/without corticosteroids for 4 weeks post‐LTx, and were then randomized (if GFR > 50 mL/min) to continued CNIs (N = 102) or subsequent conversion to EVR (N = 101). Mean calculated GFR 11 months postrandomization (ITT population) revealed no significant difference between treatments using the Cockcroft‐Gault formula (−2.9 mL/min in favor of EVR, 95%‐CI: [−10.659; 4.814], p = 0.46), whereas use of the MDRD formula showed superiority for EVR (−7.8 mL/min, 95%‐CI: [−14.366; −1.191], p = 0.021). Rates of mortality (EVR: 4.2% vs. CNI: 4.1%), biopsy‐proven acute rejection (17.7% vs. 15.3%), and efficacy failure (20.8% vs. 20.4%) were similar. Infections, leukocytopenia, hyperlipidemia and treatment discontinuations occurred more frequently in the EVR group. No hepatic artery thrombosis and no excess of wound healing impairment were noted. Conversion from CNI‐based to EVR‐based immunosuppression proved to be a safe alternative post‐LTx that deserves further investigation in terms of nephroprotection.


Liver Transplantation | 2006

Safety, tolerability, and efficacy of everolimus in de novo liver transplant recipients: 12‐ and 36‐month results

Gary A. Levy; Heinz Schmidli; Jeffrey D. Punch; Elizabeth Tuttle-Newhall; David Mayer; Peter Neuhaus; Didier Samuel; Björn Nashan; J. Klempnauer; Alan N. Langnas; Yvon Calmus; Xavier Rogiers; Michael Abecassis; Richard B. Freeman; Maarten Sloof; John P. Roberts; Lutz Fischer

Everolimus is a macrolide immunosuppressive agent with known consistent absorption. In this double‐blind study, we examined the safety and tolerability of everolimus vs. placebo in de novo liver transplant recipients. One hundred and nineteen liver allograft recipients were randomized to 1 of 4 groups: everolimus 0.5 mg bid, everolimus 1.0 mg bid, everolimus 2 mg bid, or placebo. Patients received oral cyclosporine to achieve a target trough level of 150‐400 ng/mL in combination with prednisone. Primary and secondary endpoints of safety, tolerability, and efficacy were determined at 12 months, and patients were followed through 36 months. There was a trend toward fewer treated acute rejections in the everolimus group than in the placebo group: everolimus 0.5 mg: 39.3%; everolimus 1.0 mg: 30.0%; everolimus 2 mg: 29.0%; placebo: 40.0% (P = not significant). Adverse events were higher in everolimus‐treated patients especially at the 4‐mg/day dose, but there was no difference in the incidence of thrombocytopenia or leukopenia between all groups and renal function as determined by serum creatinine, and creatinine clearance remained stable to 36 months in everolimus‐treated patients. Mean cholesterol and triglycerides increased from baseline in all treatment groups, and maximum levels were seen at 6 months. In conclusion, this study demonstrates that everolimus in combination with oral cyclosporine had an acceptable safety and tolerability profile, paving the way for additional studies in this transplant indication. Liver Transpl, 2006.


American Journal of Transplantation | 2008

Alemtuzumab (Campath-1H) and tacrolimus monotherapy after renal transplantation: results of a prospective randomized trial.

Raimund Margreiter; J. Klempnauer; Peter Neuhaus; Ferdinand Muehlbacher; C. Boesmueller; Roy Calne

The lymphocyte‐depleting antibody alemtuzumab was evaluated in a prospective randomized multicenter trial in deceased donor kidney transplantation.


World Journal of Surgery | 2000

Familial papillary thyroid carcinoma: genetics, criteria for diagnosis, clinical features, and surgical treatment.

Thomas J. Musholt; Petra B. Musholt; Thorsten Petrich; Gundula Oetting; Wolfram H. Knapp; J. Klempnauer

Hereditable predisposition to papillary thyroid carcinoma (PTC) and multinodular goiter (MNG) without evidence of an association with other malignancies as a distinct entity was recognized only recently. A meta-review of the literature on familial PTC (FPTC) was undertaken, and characteristics of families with frequent occurrence of PTC or MNG (or both) were summarized. A database on thyroid cancer patients maintained in our institution was searched for potential FPTC families. Clinical examinations were performed in 6 of 12 Hannover kindreds identified, and blood samples of all family members were collected for genetic analyses. Clinical presentations and histopathologic features of the FPTC cases were compiled. Based on the FPTC meta-review and own experience, predictive criteria to identify families at risk were developed: Exclusion criteria were previous radiation exposure and coincidence with neoplasia syndromes. Primary criteria for susceptibility to FPTC are (1) PTC in two or more first-degree relatives and (2) MNG in at least three first- or second-degree relatives of a PTC patient. Secondary criteria are diagnosis in a patient younger than 33 years, multifocal or bilateral PTC, organ-exceeding tumor growth (T4), metastasis (N1, M1), and familial accumulation of adolescent-onset thyroid disease. A hereditary predisposition to PTC is considered if both primary criteria or one primary criterion plus three secondary criteria are present. Family history-taking is recommended for all PTC patients to identify FPTC kindreds at risk. Blood relatives of FPTC index patients who harbor MNG should undergo thorough and regular clinical screening. Suspicious lesions should prompt early surgical intervention.


Nephrology Dialysis Transplantation | 2011

Increase of infectious complications in ABO-incompatible kidney transplant recipients—a single centre experience

Antje Habicht; Verena Bröker; Cornelia Blume; Johan M. Lorenzen; Mario Schiffer; Nikolaus Richter; J. Klempnauer; Hermann Haller; Frank Lehner; Anke Schwarz

BACKGROUND Due to the shortage of deceased donors ABO-incompatible (ABOi) living kidney transplantation has become a popular alternative to deceased kidney transplantation. In recent years, recipient desensitization with a combination of anti-CD20 treatment (rituximab), antigen-specific immunoadsorptions (IA) and intravenous immunoglobulin (IVIG), led to promising short-term and intermediate-term results. However, little is known about the impact of this intensified desensitization protocol on the risk of surgical and infectious complications. METHODS We retrospectively analysed 21 consecutive recipients who underwent ABOi renal transplantation. Pre-transplant desensitization included administration of rituximab (375 mg/m(2)), mycophenolate mofetil (MMF), tacrolimus and prednisolone 4 weeks prior of scheduled transplantation as well as IA and IVIG. Forty-seven patients who underwent ABO-compatible (ABOc) renal transplantation served as the control group. Medical records and electronic databases were reviewed for patient and graft survival, renal function, rate of rejections, viral and bacterial infections as well as for surgical complications (SCs) post-transplantation. RESULTS All patients showed an immediate graft function. During a mean follow-up of 15.7 ± 8.3 months (interquartile range 11.9) patient survival was 95 and 98% in the ABOi and ABOc group, respectively. Allograft survival and function, as assessed by serum creatinine levels and calculated glomerular filtration rate at 1 year, did not differ between ABOi and ABOc recipients. Furthermore, the rate of biopsy-proven acute rejections was comparable between the two groups. However, there was a trend towards more SCs within the ABOi group (29 versus 11%, non-significant). In addition, the rate of viral infections including cytomegalovirus, Herpes simplex virus, Varicella zoster virus and polyoma virus was significantly increased among the ABOi recipients (50 versus 21%; P = 0.038) despite comparable tacrolimus trough levels and MMF and steroid doses. CONCLUSIONS Our results, in line with the extended experience of other groups, demonstrate favourable short-term allograft survival and function after ABOi renal transplantation after desensitization with antigen-specific IA, IVIG and rituximab. However, the intensified desensitization was associated with an increased risk of infectious complications. This observation prompted us to briefly escalate the desensitization protocol in ABOi kidney recipients in our centre.


Liver Transplantation | 2006

Outcome and quality of life in patients with polycystic liver disease after liver or combined liver‐kidney transplantation

Gabriele I. Kirchner; Kinan Rifai; Tobias Cantz; Bjoern Nashan; Christoph Terkamp; Thomas Becker; Christian P. Strassburg; Hannelore Barg-Hock; Siegfried Wagner; Rainer Lück; J. Klempnauer; Michael P. Manns

In advanced stages of polycystic liver disease, often associated with polycystic kidney disease, a curative therapy is liver or combined liver‐kidney transplantation. However, little is known about long‐term outcome and quality of life. Between 1990 and 2003, 36 patients (32 female, 4 male) with polycystic liver or combined liver‐kidney disease underwent liver (n = 21) or liver‐kidney (n = 15) transplantation at our center. Main indications for liver transplantation were cachexia, muscle atrophy, loss of weight, recurrent cyst infections, portal hypertension, and ascites. Apart from clinical parameters, 2 anonymous questionnaires (standard short form 36 and self‐designed) addressing quality of life and social status were evaluated. Five patients (14 %) died due to sepsis or myocardial infarction with pneumonia, all within 61 days after transplantation. The follow‐up time of the remaining 31 patients ranged from 5 to 156 months, with a mean of 62 months. Of the 23 (74%) answered the questionnaires, 91% of patients felt “much better” or “better,” only 9% felt “worse” than before, and 52% of patients participated in sports regularly. Fatigue, physical fitness, loss of appetite, and vomiting improved significantly after transplantation. Physical attractiveness and interest in sex increased as well. Professional occupation did not change for 71% of patients. Family situation before and after transplantation changed in 1 case only. Finally, 78% of patients said they would opt for transplantation again, while 17% were undecided; 1 patient would not repeat transplantation. In conclusion, patients with advanced polycystic liver or polycystic liver‐kidney disease have an excellent survival rate and an improved quality of life after liver or combined liver‐kidney transplantation. Liver Transpl 12:1268‐1277, 2006.


Liver Transplantation | 2007

Failure of hepatitis B vaccination with conventional HBsAg vaccine in patients with continuous HBIG prophylaxis after liver transplantation

Jens Rosenau; Nazanin Hooman; Johannes Hadem; Kinan Rifai; Matthias J. Bahr; Gunnar Philipp; Hans L. Tillmann; J. Klempnauer; Christian P. Strassburg; Michael P. Manns

Hepatitis B vaccination after liver transplantation for hepatitis B–related liver disease has been investigated as an alternative strategy to reinfection prophylaxis with hepatitis B immunoglobulin (HBIG) with conflicting results. In most studies, HBIG treatment was discontinued before vaccination. An outstanding good response was achieved with vaccination under continuous HBIG administration using hepatitis B surface antigen (HBsAg)‐based vaccine containing special adjuvants. Both, adjuvants and continuous HBIG administration have been discussed as crucial factors for good response. Twenty‐four patients were vaccinated with conventional double dose recombinant vaccine containing 40 μg HBsAg up to 12 times at weeks 0, 2, 4 (cycle 1), 12, 14, 16 (cycle 2), 24, 26, 28 (cycle 3), and 36, 38, 40 (cycle 4). All patients received 2,000 IU HBIG every 6 weeks (4 times intravenously and 4 times intramuscularly). A significant response was defined as reconfirmed increase of anti‐HBs‐antigen (anti‐HBs) unexplained by HBIG administration or lack of anti‐HBs decrease below 100 IU/L after discontinuation of HBIG treatment after week 48. Only 2 of 24 patients (8.3%) responded significantly. Anti‐HBs started to increase after the seventh vaccination (cycle 3, during intramuscular HBIG administration) in 1 patient and after 12th vaccination (cycle 4, during intravenous HBIG administration) in the other. Maximum anti‐HBs levels were >1,000 IU/L in both patients and decreased significantly slower as compared to passive prophylaxis during follow‐up. In conclusion, the conventional HBsAg vaccine failed to induce a significant humoral immune response in most patients despite continued HBIG treatment. Further studies should address the question, of whether the use of potent adjuvant systems results in higher response rates. Liver Transpl 13: 367–373, 2007.

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Frank Lehner

Hannover Medical School

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H. Bektas

Hannover Medical School

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Kinan Rifai

Hannover Medical School

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