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John L Gerin - One of the best experts on this subject based on the ideXlab platform.
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rapid immunity to vaccination with Woodchuck hepatitis virus surface antigen using cationic liposome dna complexes as adjuvant
Journal of Medical Virology, 2009Co-Authors: Paul J. Cote, John L Gerin, Scott D Butler, Andrea L George, Jeffery Fairman, Stephan MenneAbstract:Complexes of cationic liposomes and non-coding DNA (CLDC) have shown promise as vaccine adjuvant. Using the Woodchuck animal model of hepatitis B virus (HBV) infection, the immunogenic effects of CLDC were evaluated following vaccination with three doses of Woodchuck hepatitis virus surface antigen (WHsAg) adjuvanted with either CLDC or conventional alum and administered intramuscularly (im) or subcutaneously (sc). IM vaccination with WHsAg and CLDC elicited antibodies earlier, in more Woodchucks, and with higher titers than WHsAg and alum. After two vaccine doses, antibody titers were higher following im than sc administration. Woodchucks administered two vaccine doses sc received the third vaccine dose im, and antibody responses reached titers comparable to those elicited by im administration. Following the second vaccine dose, im vaccination with WHsAg and CLDC induced T cell responses to WHsAg and selected WHs peptides and expression of the leukocyte surface marker CD8 and of the Th1 cytokines interferon-gamma and tumor necrosis factor alpha in Woodchucks. T cell responses and CD8/cytokine expression were diminished in Woodchucks from the other groups suggesting that this vaccine regimen induced a skew toward Th1 immune responses. The present study in Woodchucks demonstrates that CLDC-adjuvanted WHsAg vaccine administered im resulted in a more rapid induction of humoral and cellular immune responses compared to conventional, alum-adjuvanted WHsAg vaccine. While less rapid, the immune responses following sc administration can prime the im immune responses. This adjuvant activity of CLDC over alum may be beneficial for therapeutic vaccination in chronic HBV infection. J. Med. Virol. 81:1760–1772, 2009. © 2009 Wiley-Liss, Inc.
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chemoimmunotherapy of chronic hepatitis b virus infection in the Woodchuck model overcomes immunologic tolerance and restores t cell responses to pre s and s regions of the viral envelope protein
Journal of Virology, 2007Co-Authors: Stephan Menne, John L Gerin, Bud C Tennant, Paul J. CoteAbstract:Treatment of chronic hepatitis B virus (HBV) infection could combine potent antiviral drugs and therapeutic vaccines to overcome immunological tolerance and induce the recovery phenotype to protect against disease progression. Conventional vaccination of Woodchucks chronically infected with the Woodchuck hepatitis virus (WHV) elicited differential T-cell response profiles depending on whether or not carriers were treated with the potent antiviral drug clevudine (CLV), which significantly reduces viral and antigen loads. The differential T-cell responses defined both CLV-dependent and CLV-independent epitopes of the pre-S and S regions of the WHV envelope protein. Only combined treatment involving CLV and conventional vaccine therapeutically restored the T-cell response profile of chronic WHV carrier Woodchucks to that seen in prophylactic vaccination and in recovery from acute WHV infection. The results have implications for mechanisms of immunological tolerance operating in chronic HBV infection and suggest that such combined chemoimmunotherapy may be useful for treatment of humans with chronic HBV infection.
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antiviral effect of orally administered β d 2 aminopurine dioxolane in Woodchucks with chronic Woodchuck hepatitis virus infection
Antimicrobial Agents and Chemotherapy, 2007Co-Authors: Stephan Menne, Scott D Butler, Paul J. Cote, Raymond F. Schinazi, Andrea L George, Ghazia Asif, Jannan Narayanasamy, Selwyn J Hurwitz, John L GerinAbstract:(−)-β-d-2-Aminopurine dioxolane (APD) is a nucleoside prodrug that is efficiently converted to 9-(β-d-1,3-dioxolan-4-yl)guanine (DXG). DXG has antiviral activity in vitro against hepatitis B virus (HBV) but limited aqueous solubility, making it difficult to administer orally to HBV-infected individuals. APD is more water soluble than DXG and represents a promising prodrug for the delivery of DXG. A placebo-controlled, dose-ranging efficacy and pharmacokinetic study was conducted with Woodchucks that were chronically infected with Woodchuck hepatitis virus (WHV). APD was efficiently converted to DXG after oral and intravenous administrations of APD, with serum concentrations of DXG being higher following oral administration than following intravenous administration, suggestive of a considerable first-pass intestinal and/or hepatic metabolism. APD administered orally at 1, 3, 10, and 30 mg/kg of body weight per day for 4 weeks produced a dose-dependent antiviral response. Doses of 3 and 10 mg/kg/day reduced serum WHV viremia by 0.4 and 0.7 log 10 copies/ml, respectively. The 30-mg/kg/day dose resulted in a more pronounced, statistically significant decline in serum WHV viremia of 1.9 log 10 copies/ml and was associated with a 1.5-fold reduction in hepatic WHV DNA. Individual Woodchucks within the highest APD dose group that had declines in serum WHV surface antigen levels, WHV viremia, and hepatic WHV DNA also had reductions in hepatic WHV RNA. There was a prompt recrudescence of WHV viremia following drug withdrawal. Therefore, oral administration of APD for 4 weeks was safe in the Woodchuck model of chronic HBV infection, and the effect on serum WHV viremia was dose dependent.
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immunosuppression reactivates viral replication long after resolution of Woodchuck hepatitis virus infection
Hepatology, 2007Co-Authors: Stephan Menne, Scott D Butler, Illia A Toshkov, Paul J. Cote, John L GerinAbstract:Resolution of hepatitis B virus (HBV) infection is characterized by coordinated humoral and cellular immune responses. Immunity is durable over decades, protecting the host from reinfection and potential activation of residual HBV. Woodchucks infected at birth with Woodchuck hepatitis virus (WHV) cleared viremia and developed antibodies to surface antigen (anti-WHs). Woodchucks became seronegative for anti-WHs 3-6 years later, but in some, WHV DNA was detected in serum, liver, and/or peripheral blood mononuclear cells (PBMCs). Those with WHV DNA had increased in vitro cellular immune responses to viral antigens, CD4 and CD8 markers, and Th1-type cytokines, suggesting active WHV-specific T lymphocytes. Immunosuppression for 12 weeks using cyclosporine A in such Woodchucks resulted in transient reactivation of WHV replication. Serum of 1 Woodchuck that became positive for WHV DNA during immunosuppression was inoculated into WHV-susceptible Woodchucks, and a productive infection was demonstrated. The results indicate that after infection durable cellular immunity to WHV is essential for the long-term control of viral replication and is probably maintained by continuous priming from residual virus. Conclusion: These experimental observations demonstrate the potential of immunosuppression to reactivate HBV after resolution of infection. (HEPATOLOGY 2007;45:614–622.)
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antiviral effect of oral administration of tenofovir disoproxil fumarate in Woodchucks with chronic Woodchuck hepatitis virus infection
Antimicrobial Agents and Chemotherapy, 2005Co-Authors: Stephan Menne, Brent E Korba, Ilia A Tochkov, Scott D Butler, Paul J. Cote, Andrea L George, Shelly Xiong, John L GerinAbstract:Tenofovir disoproxil fumarate (TDF) is a nucleotide analogue approved for treatment of human immunodeficiency virus (HIV) infection. TDF also has been shown in vitro to inhibit replication of wild-type hepatitis B virus (HBV) and lamivudine-resistant HBV mutants and to inhibit lamivudine-resistant HBV in patients and HBV in patients coinfected with the HIV. Data on the in vivo efficacy of TDF against wild-type virus in non-HIV-coinfected or lamivudine-naive chronic HBV-infected patients are lacking in the published literature. The antiviral effect of oral administration of TDF against chronic Woodchuck hepatitis virus (WHV) infection, an established and predictive animal model for antiviral therapy, was evaluated in a placebo-controlled, dose-ranging study (doses, 0.5 to 15.0 mg/kg of body weight/day). Four weeks of once-daily treatment with TDF doses of 0.5, 1.5, or 5.0 mg/kg/day reduced serum WHV viremia significantly (0.2 to 1.5 log reduction from pretreatment level). No effects on the levels of anti-WHV core and anti-WHV surface antibodies in serum or on the concentrations of WHV RNA or WHV antigens in the liver of treated Woodchucks were observed. Individual TDF-treated Woodchucks demonstrated transient declines in WHV surface antigen serum antigenemia and, characteristically, these Woodchucks also had transient declines in serum WHV viremia, intrahepatic WHV replication, and hepatic expression of WHV antigens. No evidence of toxicity was observed in any of the TDF-treated Woodchucks. Following drug withdrawal there was prompt recrudescence of WHV viremia to pretreatment levels. It was concluded that oral administration of TDF for 4 weeks was safe and effective in the Woodchuck model of chronic HBV infection.
Michael Roggendorf - One of the best experts on this subject based on the ideXlab platform.
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the Woodchuck a nonprimate model for immunopathogenesis and therapeutic immunomodulation in chronic hepatitis b virus infection
Cold Spring Harbor Perspectives in Medicine, 2015Co-Authors: Michael Roggendorf, Anna D Kosinska, Mengji LuAbstract:: The Woodchuck hepatitis virus (WHV) and its host, the eastern Woodchuck, is a very valuable model system for hepatitis B virus infection. Many aspects of WHV replication and pathogenesis resemble acute and chronic hepatitis B infection in patients. Since the establishment of immunological tools, Woodchucks were used to develop new therapeutic vaccines and immunomodulatory approaches to treat chronic hepadnaviral infections. Combination therapy of nucleos(t)ide analogs, with prime-boost vaccination and triple therapy, including immunomodulatory strategies by blocking the interaction of the programmed death-1 (PD-1) receptor with its ligand inducing a potent T-cell response in chronic WHV carrier Woodchucks, suppression of viral replication, and complete elimination of the virus in 30% of the animals. Both strategies may be used for future therapies in patients with chronic hepatitis B.
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enhancing virus specific immunity in vivo by combining therapeutic vaccination and pd l1 blockade in chronic hepadnaviral infection
PLOS Pathogens, 2014Co-Authors: Jia Liu, Xiaoyong Zhang, Dongliang Yang, Baoju Wang, Anna D Kosinska, Ejuan Zhang, Inga Moller, Pia L Seiz, Dieter Glebe, Michael RoggendorfAbstract:Hepatitis B virus (HBV) persistence is facilitated by exhaustion of CD8 T cells that express the inhibitory receptor programmed cell death-1 (PD-1). Improvement of the HBV-specific T cell function has been obtained in vitro by inhibiting the PD-1/PD-ligand 1 (PD-L1) interaction. In this study, we examined whether in vivo blockade of the PD-1 pathway enhances virus-specific T cell immunity and leads to the resolution of chronic hepadnaviral infection in the Woodchuck model. The Woodchuck PD-1 was first cloned, characterized, and its expression patterns on T cells from Woodchucks with acute or chronic Woodchuck hepatitis virus (WHV) infection were investigated. Woodchucks chronically infected with WHV received a combination therapy with nucleoside analogue entecavir (ETV), therapeutic DNA vaccination and Woodchuck PD-L1 antibody treatment. The gain of T cell function and the suppression of WHV replication by this therapy were evaluated. We could show that PD-1 expression on CD8 T cells was correlated with WHV viral loads during WHV infection. ETV treatment significantly decreased PD-1 expression on CD8 T cells in chronic carriers. In vivo blockade of PD-1/PD-L1 pathway on CD8 T cells, in combination with ETV treatment and DNA vaccination, potently enhanced the function of virus-specific T cells. Moreover, the combination therapy potently suppressed WHV replication, leading to sustained immunological control of viral infection, anti-WHs antibody development and complete viral clearance in some Woodchucks. Our results provide a new approach to improve T cell function in chronic hepatitis B infection, which may be used to design new immunotherapeutic strategies in patients.
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prime boost immunization with dna and adenoviral vectors protects from hepatitis d virus hdv infection after simultaneous infection with hdv and Woodchuck hepatitis virus
Journal of Virology, 2013Co-Authors: Melanie Fiedler, Mengji Lu, Anna D Kosinska, A Schumann, Olena Brovko, Andreas Walker, Lena Johrden, Anja Mayer, Oliver Wildner, Michael RoggendorfAbstract:Hepatitis D virus (HDV) superinfection of hepatitis B virus (HBV) carriers causes severe liver disease and a high rate of chronicity. Therefore, a vaccine protecting HBV carriers from HDV superinfection is needed. To protect from HDV infection an induction of virus-specific T cells is required, as antibodies to the two proteins of HDV, p24 and p27, do not neutralize the HBV-derived envelope of HDV. In mice, HDV-specific CD8+ and CD4+ T cell responses were induced by a DNA vaccine expressing HDV p27. In subsequent experiments, seven naive Woodchucks were immunized with a DNA prime and adenoviral boost regimen prior to simultaneous Woodchuck hepatitis virus (WHV) and HDV infection. Five of seven HDV-immunized Woodchucks were protected against HDV infection, while acute self-limiting WHV infection occurred as expected. The two animals with the breakthrough had a shorter HDV viremia than the unvaccinated controls. The DNA prime and adenoviral vector boost vaccination protected Woodchucks against HDV infection in the setting of simultaneous infection with WHV and HDV. In future experiments, the efficacy of this protocol to protect from HDV infection in the setting of HDV superinfection will need to be proven.
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molecular characterization of the type i ifn receptor in two Woodchuck species and detection of its expression in liver samples from Woodchucks infected with Woodchuck hepatitis virus whv
Cytokine, 2012Co-Authors: Yang Wang, Michael Roggendorf, Mengji Lu, Xiaoyong Zhang, Yinping Lu, Zhongdong Wang, Hu Wang, Baoju Wang, Dongliang YangAbstract:Type I interferons (IFN-α/β) serve as the first line of defense against viral infection and share the same type I IFN receptor (IFNAR) complex, which is composed of IFNAR1 and -2. The Eastern Woodchuck (Marmota monax) and Chinese Woodchuck (Marmota himalayana) are suitable for studying hepatitis B virus (HBV) infection. Here, the complete or partial sequences of the IFNARs of both species were obtained and analyzed. Small interference RNAs targeting wIFNAR1 and -2 specifically down-regulated the expression of wIFNAR1 and -2 and the IFN-stimulated gene MxA in a Woodchuck cell line, respectively. IFNAR2 was significantly up-regulated in primary Woodchuck hepatocytes stimulated with IFN-α or -γ. The expression of Woodchuck IFNAR1 and -2 was decreased in Woodchucks chronically infected with Woodchuck hepatitis virus (WHV). These results are essential for studying type I IFN-related innate immunity and therapy in hepadnaviral infection in the Woodchuck model.
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the expression of pd 1 ligands and their involvement in regulation of t cell functions in acute and chronic Woodchuck hepatitis virus infection
PLOS ONE, 2011Co-Authors: Ejuan Zhang, Michael Roggendorf, Xiaoyong Zhang, Dongliang Yang, Baoju Wang, Anna D Kosinska, Ulf Dittmer, Yang Xu, Yongjun Tian, Mengji LuAbstract:Background The programmed cell death 1 (PD-1)/programmed death-1 ligand 1 (PD-L1) system may play a role in the negative regulation of T cell functions in hepatitis B virus (HBV) infection. Thus, it is important to study its role in the widely used animal model for HBV infection of Woodchucks with Woodchuck hepatitis virus (WHV). Methods Woodchuck PD-L1 (wPD-L1) and -L2 (wPD-L2) were cloned and characterized. The levels of wPD-L1 expression in primary Woodchuck hepatocytes (PWH), peripheral blood mononuclear cells (PBMCs), and liver tissue of naive and WHV-infected Woodchucks were examined by real time reverse transcription (RT)-PCR and flow cytometry. Using antibodies against wPD-L1 and -L2, the effect of blocking PD-1/PD-L1/PD-L2 interaction on the proliferation and degranulation of Woodchuck PBMCs was examined. Principal Findings Both wPD-L1 and -L2 showed a high homology to their counterparts of other mammalian species and humans. WPD-L1 expression in PWH and PBMCs of naive animals was low but could be stimulated by Toll-like receptor (TLR) ligands and interferons (IFN). WPD-L1 expression in liver tissue was significantly higher than that measured in PWHs and was slightly elevated during acute and chronic WHV infection. However, wPD-1 and wPD-L1 expression on PBMCs was strongly up-regulated during acute and chronic infection. In vitro blockade with antibodies against wPD-L1 and -L2 partially enhanced proliferation and degranulation of PBMCs from WHV-infected Woodchucks. Conclusions Our results demonstrated that wPD-1/wPD-L1 expression in hepatocytes and PBMCs can be induced by different inflammatory stimuli and is up-regulated mainly on PBMCs during WHV infection. A blockade of the Woodchuck PD-1/PD-L pathway could partially enhance T cell functions in WHV infection.
Stephan Menne - One of the best experts on this subject based on the ideXlab platform.
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Combination Treatment with the Vimentin-Targeting Antibody hzVSF and Tenofovir Suppresses Woodchuck Hepatitis Virus Infection in Woodchucks
'MDPI AG', 2021Co-Authors: Kyle E. Korolowicz, Xu Huang, Changsuek Yon, Bhaskar Kallakury, Manasa Suresh, Kyoung-pil Lee, Sungman Park, Yoon-won Kim, Stephan MenneAbstract:Current treatment options for patients infected with hepatitis B virus (HBV) are suboptimal, because the approved drugs rarely induce cure due to the persistence of the viral DNA genome in the nucleus of infected hepatocytes, and are associated with either severe side effects (pegylated interferon-alpha) or require life-long administration (nucleos(t)ide analogs). We report here the evaluation of the safety and therapeutic efficacy of a novel, humanized antibody (hzVSF) in the Woodchuck model of HBV infection. hzVSF has been shown to act as a viral entry inhibitor, most likely by suppressing vimentin-mediated endocytosis of virions. Targeting the increased vimentin expression on liver cells by hzVSF after infection with HBV or Woodchuck hepatitis virus (WHV) was demonstrated initially. Thereafter, hzVSF safety was assessed in eight Woodchucks naïve for WHV infection. Antiviral efficacy of hzVSF was evaluated subsequently in 24 chronic WHV carrier Woodchucks by monotreatment with three ascending doses and in combination with tenofovir alafenamide fumarate (TAF). Consistent with the proposed blocking of WHV reinfection, intravenous hzVSF administration for 12 weeks resulted in a modest but transient reduction of viral replication and associated liver inflammation. In combination with oral TAF dosing, the antiviral effect of hzVSF was enhanced and sustained in half of the Woodchucks with an antibody response to viral proteins. Thus, hzVSF safely but modestly alters chronic WHV infection in Woodchucks; however, as a combination partner to TAF, its antiviral efficacy is markedly increased. The results of this preclinical study support future evaluation of this novel anti-HBV drug in patients
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liver targeted toll like receptor 7 agonist combined with entecavir promotes a functional cure in the Woodchuck model of hepatitis b virus
Hepatology Communications, 2019Co-Authors: Kyle E Korolowizc, Xu Huang, Changsuek Yon, Evelyn Rodrigo, Manny Corpuz, David Plouffe, Bhaskar Kallakury, Manasa Suresh, Andrew T Miller, Stephan MenneAbstract:Current therapeutics for chronic infection with hepatitis B virus (HBV) rarely induce functional cure due to the immunotolerant status of patients. Small molecule agonists targeting toll-like receptor 7 (TLR7) have been shown to elicit a functional cure in animal models of HBV but sometimes with poor tolerability due to immune-related toxicities. In an effort to increase the therapeutic window of TLR7 agonists to treat chronic hepatitis B (CHB), we developed an oral TLR7 agonist, APR002, designed to act locally in the gastrointestinal tract and liver, thus minimizing systemic exposure and improving tolerability. Here, we describe the pharmacokinetic/pharmacodynamic (PK/PD) profile of APR002 in mice and uninfected Woodchucks as well as the safety and antiviral efficacy in combination with entecavir (ETV) in Woodchucks with CHB. Treatment of Woodchucks chronically infected with Woodchuck hepatitis virus (WHV) with weekly oral doses of APR002 was well-tolerated. While APR002 and ETV single agents did not elicit sustained viral control, combination therapy resulted in durable immune-mediated suppression of the chronic infection. These Woodchucks also had detectable antibodies to viral antigens, enhanced interferon-stimulated gene expression, and loss of WHV covalently closed circular DNA. Conclusion: APR002 is a novel TLR7 agonist exhibiting a distinct PK/PD profile that in combination with ETV can safely attain a functional cure in Woodchucks with chronic WHV infection. Our results support further investigation of liver-targeted TLR7 agonists in human CHB.
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down regulation of hepatitis delta virus super infection in the Woodchuck model
Virology, 2019Co-Authors: Tetyana Lukash, Natalia Freitas, Stephan Menne, Severin O GudimaAbstract:Abstract Mechanisms mediating clearance of hepatitis delta virus (HDV) are poorly understood. This study analyzed in detail profound down-regulation of HDV infection in the Woodchuck model. Super-infection with HDV of Woodchucks chronically infected with HBV-related Woodchuck hepatitis virus produced two patterns. In the first, HDV viremia had a sharp peak followed by a considerable decline, and initial rise of HDV virions' infectivity followed by abrupt infectivity loss. In the second, HDV titer rose and later displayed plateau-like profile with high HDV levels; and HDV infectivity became persistently high when HDV titer reached the plateau. The infectivity loss was not due to defects in the virions' envelope, binding to anti-envelope antibodies, or mutations in HDV genome, but it correlated with profound reduction of the replication capacity of virion-associated HDV genomes. Subsequent finding that in virions with reduced infectivity most HDV RNAs were not full-length genomes suggests possible HDV clearance via RNA fragmentation.
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RESEARCH ARTICLE AIC649 Induces a Bi-Phasic Treatment Response in the Woodchuck Model of Chronic Hepatitis
2016Co-Authors: Daniela Paulsen, Bud C Tennant, Olaf Weber, Helga Ruebsamen-schaeff, Stephan MenneAbstract:AIC649 has been shown to directly address the antigen presenting cell arm of the host immune defense leading to a regulated cytokine release and activation of T cell responses. In the present study we analyzed the antiviral efficacy of AIC649 as well as its potential to induce functional cure in animal models for chronic hepatitis B. Hepatitis B virus transgenic mice and chronically Woodchuck hepatitis virus (WHV) infected Woodchucks were treated with AIC649, respectively. In the mouse system AIC649 decreased the hepatitis B virus titer as effective as the “gold standard”, Tenofovir. Interestingly, AIC649-treated chronically WHV infected Woodchucks displayed a bi-phasic pattern of response: The marker for func-tional cure—hepatitis surface antigen—first increased but subsequently decreased even after cessation of treatment to significantly reduced levels. We hypothesize that the observed bi-phasic response pattern to AIC649 treatment reflects a physiologically “con-certed”, reconstituted immune response against WHV and therefore may indicate a poten-tial for inducing functional cure in HBV-infected patients
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aic649 induces a bi phasic treatment response in the Woodchuck model of chronic hepatitis b
PLOS ONE, 2015Co-Authors: Daniela Paulsen, Bud C Tennant, Olaf Weber, Helga Ruebsamenschaeff, Stephan MenneAbstract:AIC649 has been shown to directly address the antigen presenting cell arm of the host immune defense leading to a regulated cytokine release and activation of T cell responses. In the present study we analyzed the antiviral efficacy of AIC649 as well as its potential to induce functional cure in animal models for chronic hepatitis B. Hepatitis B virus transgenic mice and chronically Woodchuck hepatitis virus (WHV) infected Woodchucks were treated with AIC649, respectively. In the mouse system AIC649 decreased the hepatitis B virus titer as effective as the “gold standard”, Tenofovir. Interestingly, AIC649-treated chronically WHV infected Woodchucks displayed a bi-phasic pattern of response: The marker for functional cure—hepatitis surface antigen—first increased but subsequently decreased even after cessation of treatment to significantly reduced levels. We hypothesize that the observed bi-phasic response pattern to AIC649 treatment reflects a physiologically “concerted”, reconstituted immune response against WHV and therefore may indicate a potential for inducing functional cure in HBV-infected patients.
Paul J. Cote - One of the best experts on this subject based on the ideXlab platform.
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sustained efficacy and seroconversion with the toll like receptor 7 agonist gs 9620 in the Woodchuck model of chronic hepatitis b
Journal of Hepatology, 2015Co-Authors: Stephan Menne, Christine A Bellezza, B H Baldwin, Paul J. Cote, Jim Zheng, Daniel B Tumas, Katherine H Liu, Linta M Thampi, Dalal Aldeghaither, Randall L HalcombAbstract:Background & Aims New therapies for chronic hepatitis B (CHB) are urgently needed since current treatments rarely lead to cure. We evaluated whether the oral small molecule toll-like receptor (TLR7) agonist GS-9620 could induce durable antiviral efficacy in Woodchucks chronically infected with Woodchuck hepatitis virus (WHV), a hepadnavirus closely related to human hepatitis B virus (HBV). Methods After evaluating the pharmacokinetics, pharmacodynamics and tolerability of oral GS-9620 in uninfected Woodchucks, adult Woodchucks chronically infected with WHV (n=7 per group) were dosed with GS-9620 or placebo for 4 or 8weeks with different treatment schedules. Results GS-9620 treatment induced rapid, marked and sustained reduction in serum viral DNA (mean maximal 6.2log 10 reduction), and hepatic WHV DNA replicative intermediates, WHV cccDNA and WHV RNA, as well as loss of detectable serum WHV surface antigen (WHsAg). GS-9620 treatment also induced a sustained antibody response against WHsAg in a subset of animals. Strikingly, treatment reduced the incidence of hepatocellular carcinoma (HCC) from 71% in the placebo group to 8% in GS-9620-treated Woodchucks with sustained viral load reduction. GS-9620 treatment was associated with reversible increases in serum liver enzymes and thrombocytopenia, and induced intrahepatic CD8 + T cell, NK cell, B cell and interferon response transcriptional signatures. Conclusions The data demonstrate that short duration, finite treatment with the oral TLR7 agonist GS-9620 can induce a sustained antiviral response in the Woodchuck model of CHB, and support investigation of this compound as a therapeutic approach to attain a functional cure in CHB patients.
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identification of an intrahepatic transcriptional signature associated with self limiting infection in the Woodchuck model of hepatitis b
Hepatology, 2013Co-Authors: Simon P Fletcher, Paul J. Cote, Daniel J Chin, Donavan T Cheng, Palanikumar Ravindran, Hans Bitter, Lore Gruenbaum, Klaus Klumpp, Stephan MenneAbstract:Approximately 350 million individuals live with chronic hepatitis B (CHB), and over half a million people are estimated to die each year due to HBV-associated liver diseases, such as cirrhosis and hepatocellular carcinoma (HCC) (1). Defining the immune determinants of viral clearance during acute hepatitis B (AHB) and during successful treatment of CHB will likely support the development of improved therapeutic strategies to treat HBV infection. However, since the current therapies for CHB rarely lead to cure (2), and identification of patients in the early preclinical phase of AHB is challenging, animal models have been used to characterize the immune requirements of viral control. Studies of acute HBV infection in chimpanzees have identified the central role of CD8+ T cells in the resolution of viral infection (3, 4), and studies in transgenic (5, 6) and hydrodynamic (7) mouse models have also identified potentially important determinants of HBV clearance. Since ethical and cost issues limit the use of chimpanzees for biomedical research and there is no small animal model of natural HBV infection, further dissection of the host-virus interactions during self-limiting infection would greatly benefit from the availability of an alternative, well characterized, immunocompetent animal model of AHB. The Eastern Woodchuck (Marmota monax) is naturally infected with WHV, a hepadnavirus closely related to human HBV. After experimental infection of neonatal Woodchucks with WHV, 25-40% of animals resolve the infection, while the remainder become persistently infected and subsequently develop HCC (8). Therefore, the Woodchuck has been used in a number of studies to characterize the immune correlates of viral control (9-12), but the lack of sequence information has previously precluded global transcriptional analysis. To address this major limitation of the model, we recently described the sequencing, assembly and annotation of the Woodchuck transcriptome, together with the generation of custom Woodchuck microarrays (13). Using this new platform, we initially characterized the intrahepatic transcriptional profiles of persistent WHV infection, and identified important parallels between the immune response to WHV in Woodchucks and HBV in man (13). Since this first study established the translational value of the Woodchuck model, we have now utilized the Woodchuck microarray to characterize the immune determinants of WHV clearance during self-limiting infection.
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identification of an intrahepatic transcriptional signature associated with self limiting infection in the Woodchuck model of hepatitis b
Hepatology, 2013Co-Authors: Simon P Fletcher, Paul J. Cote, Daniel J Chin, Donavan T Cheng, Palanikumar Ravindran, Hans Bitter, Lore Gruenbaum, Klaus Klumpp, Stephan MenneAbstract:The Woodchuck model of hepatitis B virus (HBV) infection displays many characteristics of human infection and has particular value for characterizing the host immune responses during the development of chronic infection. Using the newly developed custom Woodchuck microarray platform, we compared the intrahepatic transcriptional profiles of neonatal Woodchucks with self-limiting Woodchuck hepatitis virus (WHV) infection to those Woodchucks progressing to persistent WHV infection. This revealed that WHV does not induce significant intrahepatic gene expression changes during the early-acute stage of infection (8 weeks), suggesting it is a stealth virus. At the mid-acute phase of infection (14 weeks), resolution was associated with induction of a prominent cytotoxic T-cell signature. Strikingly, this was accompanied by high-level expression of PD-1 and various other inhibitory T-cell receptors, which likely act to minimize liver damage by cytotoxic T cells during viral clearance. In contrast to the expression of perforin and other cytotoxic effector genes, the interferon-γ (IFN-γ) signaling response in the mid-acute phase was comparable to that in chronically infected adult animals. The absence of a strong IFN-α/β transcriptional response indicated that type I IFN is not a critical mediator of self-limiting infection. Nevertheless, a number of antiviral genes, including viperin, were differentially expressed during resolving infection, suggesting that a subset of IFN-stimulated genes (ISG) may play a role in the control of WHV replication. Conclusion: We identified new immune pathways associated with the clearance of hepadnavirus infection revealing novel molecular targets with potential for the therapeutic treatment of chronic hepatitis B. (HEPATOLOGY 2013)
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rapid immunity to vaccination with Woodchuck hepatitis virus surface antigen using cationic liposome dna complexes as adjuvant
Journal of Medical Virology, 2009Co-Authors: Paul J. Cote, John L Gerin, Scott D Butler, Andrea L George, Jeffery Fairman, Stephan MenneAbstract:Complexes of cationic liposomes and non-coding DNA (CLDC) have shown promise as vaccine adjuvant. Using the Woodchuck animal model of hepatitis B virus (HBV) infection, the immunogenic effects of CLDC were evaluated following vaccination with three doses of Woodchuck hepatitis virus surface antigen (WHsAg) adjuvanted with either CLDC or conventional alum and administered intramuscularly (im) or subcutaneously (sc). IM vaccination with WHsAg and CLDC elicited antibodies earlier, in more Woodchucks, and with higher titers than WHsAg and alum. After two vaccine doses, antibody titers were higher following im than sc administration. Woodchucks administered two vaccine doses sc received the third vaccine dose im, and antibody responses reached titers comparable to those elicited by im administration. Following the second vaccine dose, im vaccination with WHsAg and CLDC induced T cell responses to WHsAg and selected WHs peptides and expression of the leukocyte surface marker CD8 and of the Th1 cytokines interferon-gamma and tumor necrosis factor alpha in Woodchucks. T cell responses and CD8/cytokine expression were diminished in Woodchucks from the other groups suggesting that this vaccine regimen induced a skew toward Th1 immune responses. The present study in Woodchucks demonstrates that CLDC-adjuvanted WHsAg vaccine administered im resulted in a more rapid induction of humoral and cellular immune responses compared to conventional, alum-adjuvanted WHsAg vaccine. While less rapid, the immune responses following sc administration can prime the im immune responses. This adjuvant activity of CLDC over alum may be beneficial for therapeutic vaccination in chronic HBV infection. J. Med. Virol. 81:1760–1772, 2009. © 2009 Wiley-Liss, Inc.
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Serologic Survey of Woodchuck Hepatitis Virus in North Carolina Woodchucks (Marmota monax)
Journal of Zoo and Wildlife Medicine, 2008Co-Authors: John M. Cullen, D. Lindsey-pegram, Paul J. CoteAbstract:Abstract The prevalence of Woodchuck hepatitis virus (WHV) in wild populations of Woodchucks is understudied and therefore unclear. Although infection is common in the southeastern region of Pennsylvania and surrounding states, it is virtually absent in New York and New England. Sera were collected from wild Woodchucks from Orange County, North Carolina and tested for the presence of markers of current or previous infection with WHV. Of the 24 Woodchucks tested, there were three animals (12.5%) with WHV surface antigen as well as antibodies to Woodchuck hepatitis core antigen in their serum, indicative of active infection. There were four (17%) animals with antibodies to WHV core antigen but no Woodchuck hepatitis surface antigen, indicative of prior infections. The remaining 17 animals had no detectable markers of WHV infection. These data indicate that WHV is present in central North Carolina at rates approaching those seen in endemic areas, such as the mid-Atlantic region of the United States.
Bud C Tennant - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE AIC649 Induces a Bi-Phasic Treatment Response in the Woodchuck Model of Chronic Hepatitis
2016Co-Authors: Daniela Paulsen, Bud C Tennant, Olaf Weber, Helga Ruebsamen-schaeff, Stephan MenneAbstract:AIC649 has been shown to directly address the antigen presenting cell arm of the host immune defense leading to a regulated cytokine release and activation of T cell responses. In the present study we analyzed the antiviral efficacy of AIC649 as well as its potential to induce functional cure in animal models for chronic hepatitis B. Hepatitis B virus transgenic mice and chronically Woodchuck hepatitis virus (WHV) infected Woodchucks were treated with AIC649, respectively. In the mouse system AIC649 decreased the hepatitis B virus titer as effective as the “gold standard”, Tenofovir. Interestingly, AIC649-treated chronically WHV infected Woodchucks displayed a bi-phasic pattern of response: The marker for func-tional cure—hepatitis surface antigen—first increased but subsequently decreased even after cessation of treatment to significantly reduced levels. We hypothesize that the observed bi-phasic response pattern to AIC649 treatment reflects a physiologically “con-certed”, reconstituted immune response against WHV and therefore may indicate a poten-tial for inducing functional cure in HBV-infected patients
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aic649 induces a bi phasic treatment response in the Woodchuck model of chronic hepatitis b
PLOS ONE, 2015Co-Authors: Daniela Paulsen, Bud C Tennant, Olaf Weber, Helga Ruebsamenschaeff, Stephan MenneAbstract:AIC649 has been shown to directly address the antigen presenting cell arm of the host immune defense leading to a regulated cytokine release and activation of T cell responses. In the present study we analyzed the antiviral efficacy of AIC649 as well as its potential to induce functional cure in animal models for chronic hepatitis B. Hepatitis B virus transgenic mice and chronically Woodchuck hepatitis virus (WHV) infected Woodchucks were treated with AIC649, respectively. In the mouse system AIC649 decreased the hepatitis B virus titer as effective as the “gold standard”, Tenofovir. Interestingly, AIC649-treated chronically WHV infected Woodchucks displayed a bi-phasic pattern of response: The marker for functional cure—hepatitis surface antigen—first increased but subsequently decreased even after cessation of treatment to significantly reduced levels. We hypothesize that the observed bi-phasic response pattern to AIC649 treatment reflects a physiologically “concerted”, reconstituted immune response against WHV and therefore may indicate a potential for inducing functional cure in HBV-infected patients.
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abstract 5144 low dose sorafenib delays hepatocellular cancer hcc development in the Woodchuck model of hepatitis b related hcc
Cancer Research, 2015Co-Authors: Renuka Iyer, Bud C Tennant, Ilia Toshkov, Leslie Curtin, Sandra Sexton, Gerald J Fetterly, Orla Maguire, Hans Minderman, Alan D Hutson, Donald L TrumpAbstract:Introduction: The eastern Woodchuck is an established model of human hepatitis B viral infection and spontaneously develops HCC in the context of chronic Woodchuck hepatitis viral infection (WHV) at a median age of 24 months. In this translational model of angiogenesis driven HCC, we evaluated the impact of sorafenib on delaying HCC development. Methods: Woodchucks were bred and inoculated at birth with titered infectious WHV pools obtained from chronic WHV carriers. By 12 months of age, the rate of chronic WHV infection was >60%. Animals were trained to receive drug orally mixed in a liquid diet. After an initial single dose Woodchuck PK study it was predicted that sorafenib given orally M-F at 2.5 mg/kg once daily or 5mg/kg daily would achieve exposure in Woodchucks ∼ 2x IC50 and 5X IC50 for all targets of sorafenib. This is within the exposure achieved in humans where the starting dose achieves exposures that are ∼ 10-12X IC50. We hypothesized that for both long term tolerability and delaying of HCC development, lower doses maybe ideal. Viral titers of WHV DNA were serially assessed, PK exposure of sorafenib and serial ultrasound (USG) was done q2 weeks to assess HCC development. Six WHV+ animals of similar age per arm were randomized to Placebo (P), low or high dose sorafenib. Time to tumor development (TTD) was measured from start of therapy to first occurrence of at least one 2 cm HCC was confirmed on 2 serial USGs. Tumor volume of all tumors seen was assessed as tumor burden. Results: Median TTD was 393 days, 490 and 498 days in the P, low and high dose sorafenib groups respectively. No toxicity was seen and PK results showed exposures as predicted in the two sorafenib groups. The tumor burden adjusted for the duration of therapy was significantly lower in the low dose group than the high dose and P groups. We evaluated three possible mechansims for this delay in HCC. WHV titers decreased as tumor burden increased as viral replication halts when malignant transformation occurs. The delay in TTD was not secondary to an antiviral effect that is known in this model and in humans to delay HCC occurrence. Anti-angiogenic effect was measured on H/E following necropsy as tumor necrosis and involved 7% of the total tumor volume in low dose and 13% of total tumor volume in high dose animals and 0% in P animals. High dose sorafenib inhibited the ex-vivo mixed lymphocyte reaction of Woodchuck PBMC whereas low dose sorafenib did not which mechanistically may explain the difference seen in tumor burden with low compared to high dose sorafenib. Conclusions: The delay in HCC by 100 days seen in Woodchucks would translate into a 3-9 years delay in HCC occurrence in humans. The tolerability at low dose for over 2 years, lower tumor burden and differential immune effects seen at low dose vs higher dose have great translational significance in the light of the recently completed STORM trial. Support: Sorafenib: Bayer. Funding: ACS- MSRG 08-096-01-CCE Citation Format: Renuka V. Iyer, Sandra Sexton, Leslie Curtin, Gerald Fetterly, Orla Maguire, Hans Minderman, Ilia Toshkov, Bud Tennant, Alan Hutson, Donald L. Trump, Candace Johnson. Low dose sorafenib delays hepatocellular cancer (HCC) development in the Woodchuck model of hepatitis B related HCC. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5144. doi:10.1158/1538-7445.AM2015-5144
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abstract 4946 developing anti angiogenic therapies for human hepatocellular cancer hcc studies of suntinib in the Woodchuck model of hepatitis b related hcc
Cancer Research, 2014Co-Authors: Alexander Pomakov, Bud C Tennant, Ilia Toshkov, Sandra Buitrago, Leslie Curtin, Donald L Trump, Candace S Johnson, Edward Ashton, Renuka IyerAbstract:Introduction: Better animal models that recapitulate the liver milieu of human HCC are needed. The eastern Woodchuck is an established model of human hepatitis B viral infection and spontaneously develops HCC in the context of chronic Woodchuck hepatitis viral infection (WHV). The translational relevance of this model for developing anti-angiogenic therapies was evaluated using sunitinib (S), a potent oral, anti-angiogenic agent. Methods: Woodchucks were bred and inoculated at birth with titered infectious WHV pools obtained from chronic WHV carriers. By 12 months of age, the rate of chronic WHV infection was >60%. Carriers were followed by USG, upon developing HCC, 12 animals were randomized 1:1 to S or placebo (P) given once orally daily for 30 days. From a single treatment S PK study at 4 dose levels, n=3/group, simulations showed 12mg/kg daily was expected to be optimal for achieving steady state serum concentrations between 50- 100 ng/ml in Woodchucks. Tumor size and blood flow were assessed using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) before treatment and on day 28 using standardized protocols. At study completion or when animals were humanely euthanized, tumors and any other small nodules were fixed overnight in 10% buffered formalin. After standard processing and embedding in paraffin, 4 μm sections were prepared, deparaffinized, stained with hematoxylin-eosin (HE 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4946. doi:10.1158/1538-7445.AM2014-4946
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semliki forest virus expressing interleukin 12 induces antiviral and antitumoral responses in Woodchucks with chronic viral hepatitis and hepatocellular carcinoma
Journal of Virology, 2009Co-Authors: Juan R Rodriguezmadoz, Christine A Bellezza, Scott D Butler, Katherine H Liu, Jose I Quetglas, Marta Ruizguillen, Itziar Otano, Julien Crettaz, Nathan L Dykes, Bud C TennantAbstract:A vector based on Semliki Forest virus (SFV) expressing high levels of interleukin-12 (SFV-enhIL-12) has previously demonstrated potent antitumoral efficacy in small rodents with hepatocellular carcinoma (HCC) induced by transplantation of tumor cells. In the present study, the infectivity and antitumoral/antiviral effects of SFV vectors were evaluated in the clinically more relevant Woodchuck model, in which primary HCC is induced by chronic infection with Woodchuck hepatitis virus (WHV). Intratumoral injection of SFV vectors expressing luciferase or IL-12 resulted in high reporter gene activity within tumors and cytokine secretion into serum, respectively, demonstrating that SFV vectors infect Woodchuck tumor cells. For evaluating antitumoral efficacy, Woodchuck tumors were injected with increasing doses of SFV-enhIL-12, and tumor size was measured by ultrasonography following treatment. In five (83%) of six Woodchucks, a dose-dependent, partial tumor remission was observed, with reductions in tumor volume of up to 80%, but tumor growth was restored thereafter. Intratumoral treatment further produced transient changes in WHV viremia and antigenemia, with ≥1.5-log 10 reductions in serum WHV DNA in half of the Woodchucks. Antitumoral and antiviral effects were associated with T-cell responses to tumor and WHV antigens and with expression of CD4 and CD8 markers, gamma interferon, and tumor necrosis factor alpha in peripheral blood mononuclear cells, suggesting that immune responses against WHV and HCC had been induced. These experimental observations suggest that intratumoral administration of SFV-enhIL-12 may represent a strategy for treatment of chronic HBV infection and associated HCC in humans but indicate that this approach could benefit from further improvements.
