Publications (209) View all
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Article: Epidermal growth factor improves lentivirus vector gene transfer into primary mouse hepatocytes.
M Rothe, I Rittelmeyer, M Iken, U Rüdrich, A Schambach, S Glage, M P Manns, C Baum, M Bock, M Ott, U Modlich[show abstract] [hide abstract]
ABSTRACT: Partial resistance of primary mouse hepatocytes to lentiviral (LV) vector transduction poses a challenge for ex vivo gene therapy protocols in models of monogenetic liver disease. We thus sought to optimize ex vivo LV gene transfer while preserving the hepatocyte integrity for subsequent transplantation into recipient animals. We found that culture media supplemented with epidermal growth factor (EGF) and, to a lesser extent, hepatocyte growth factor (HGF) markedly improved transduction efficacy at various multiplicities of infection. Up to 87% of primary hepatocytes were transduced in the presence of 10 ng EGF, compared with ~30% in standard culture medium (SCMs). The increased number of transgene-expressing cells correlated with increased nuclear import and more integrated pro-viral copies per cell. Higher LV transduction efficacy was not associated with proliferation, as transduction capacity of gammaretroviral vectors remained low (<1%). Finally, we developed an LV transduction protocol for short-term (maximum 24 h) adherent hepatocyte cultures. LV-transduced hepatocytes showed liver repopulation capacities similar to freshly isolated hepatocytes in alb-uPA mouse recipients. Our findings highlight the importance of EGF for efficient LV transduction of primary hepatocytes in culture and should facilitate studies of LV gene transfer in mouse models of monogenetic liver disease.Gene therapy 08/2011; 19(4):425-34. · 4.75 Impact Factor -
Article: Regional transient portal ischemia and irradiation as preparative regimen for hepatocyte transplantation.
S Koenig, Q Yuan, P Krause, H Christiansen, M Rave-Fraenk, S Kafert-Kasting, H Kriegbaum, A Schneider, M Ott, J Meyburg[show abstract] [hide abstract]
ABSTRACT: Hepatocyte transplantation is regarded as a promising option to correct hereditary metabolic liver disease. This study describes a novel method involving regional transient portal ischemia (RTPI) in combination with hepatic irradiation (IR) as a preparative regimen for hepatocyte transplantation. The right lobules of rat livers (45% of liver mass) were subjected to RTPI of 30-120 min. Liver specimens and serum samples were analyzed for transaminase levels, DNA damage, apoptosis, and proliferation. Repopulation experiments involved livers of dipeptidylpeptidase IV (DPPIV)-deficient rats preconditioned with RTPI (60-90 min) either with or without prior partial hepatic IR (25 Gy). After reperfusion intervals of 1 and 24 h, 12 million wild-type (DPPIV positive) hepatocytes were transplanted into recipient livers via the spleen. RTPI of 60-90 min caused limited hepatic injury through necrosis and induced a distinct regenerative response in the host liver. Twelve weeks following transplantation, small clusters of donor hepatocytes were detected within the portal areas. Quantitative analysis revealed limited engraftment of 0.79% to 2.95%, whereas control animals (sham OP) exhibited 4.16% (determined as relative activity of DPPIV when compared to wild-type liver). Repopulation was significantly enhanced (21.43%) when IR was performed prior to RTPI, optimum preconditioning settings being 90 min of ischemia and 1 h of reperfusion before transplantation. We demonstrate that RTPI alone is disadvantageous to donor cell engraftment, whereas the combination of IR with RTPI comprises an effective preparative regimen for liver repopulation. The method described clearly has potential for clinical application.Cell Transplantation 01/2011; 20(2):303-11. · 5.13 Impact Factor -
Article: Fulminant hepatic failure due to chemotherapy-induced hepatitis B reactivation: role of rituximab.
M A Stange, O Tutarel, S Pischke, A Schneider, C P Strassburg, T Becker, H Barg-Hock, M Bastürk, K Wursthorn, M Cornberg, M Ott, T F Greten, M P Manns, H Wedemeyer[show abstract] [hide abstract]
ABSTRACT: Hepatitis B virus reactivation during immunosuppressive therapies can lead to liver failure with very limited treatment options available. We report here on two cases of severe hepatitis B reactivation during chemotherapy including rituximab for B cell lymphoma which were treated with liver or liver-cell transplantation. Liver function was normal and HBV infection was unknown in both patients before chemotherapy was started. Impaired liver function became apparent after 4 and 6 courses of chemotherapy, respectively, and both patients experienced fulminant hepatic failure despite antiviral treatment with lamivudine or entecavir. Patient A underwent liver transplantation after documentation of complete remission of the lymphoma and survived without any evidence for hepatitis B recurrence. Patient B received 4 courses of hepatocyte transplantation but did not survive. These cases underline the importance of anti-HBc screening in patients receiving immunosuppressive treatments in particular when rituximab is given. Pre-emptive antiviral treatments should be administered since delayed antiviral treatment is frequently unable to prevent liver failure.Zeitschrift für Gastroenterologie 02/2010; 48(2):258-63. · 0.90 Impact Factor -
Article: House dust mite control measures for asthma.
Allergy 09/2009; 64(9):1404; author reply 1405. · 6.27 Impact Factor -
SourceAvailable from: Stefania Bocconi
Chapter: Documenting the eAccessibility of educational software: supporting informed choices for a more inclusive classroom
[show abstract] [hide abstract]
ABSTRACT: This paper deals with the problem of providing and disseminating information about the accessibility fea- tures of educational software products. Its ultimate aim is to support educational actors in choosing tools that facilitate the inclusion of pupils with disabilities into everyday classroom activities. It focuses both on the type of information to be conveyed and on the way to do so, and, more precisely, it seeks to answer the question: “In the field of educational software what kind of information about accessibility features is actually needed by potential users and how should it be delivered”?01/2006: pages 2029-2033; , ISBN: 9788469024744