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Abstract
BACKGROUND In utero transplantation (IUT) of hematopoietic stem cells has the potential to treat a large number of hematologic and metabolic diseases amenable to partial replacement of the hematopoietic system. METHODS A review of the literature was conducted that focused on the clinical and experimental experience with IUT and, in this context, the development of the hematopoietic and immune systems. RESULTS Successful application of IUT has been limited to the treatment of various types of immunodeficiencies that affect lymphocyte development and function. Other congenital defects such as the thalassemias have not resulted in clinically significant engraftment. Recent efforts at understanding and overcoming the barriers to engraftment in the fetus have focused on providing a selective advantage to donor stem cells and fostering immune tolerance toward the donor cells. The critical cellular components of the graft that promote engraftment and tolerance induction are being evaluated in animal models. Improvements in engraftment have resulted from the inclusion of T cells and/or dendritic cells in the graft, as well as a strategy of combined prenatal and postnatal transplantation. CONCLUSIONS The advantages, necessity, and benefits of early treatment will continue to encourage development of IUT as a means to treat hematopoietic and other types of birth defects.
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Affiliation(s)
- Marcus O Muench
- Department of Laboratory Medicine, University of California, San Francisco, CA 94143, USA.
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2
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Scheer N, Wilson ID. A comparison between genetically humanized and chimeric liver humanized mouse models for studies in drug metabolism and toxicity. Drug Discov Today 2015; 21:250-63. [PMID: 26360054 DOI: 10.1016/j.drudis.2015.09.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Revised: 08/07/2015] [Accepted: 09/01/2015] [Indexed: 12/12/2022]
Abstract
Mice that have been genetically humanized for proteins involved in drug metabolism and toxicity and mice engrafted with human hepatocytes are emerging and promising in vivo models for an improved prediction of the pharmacokinetic, drug-drug interaction and safety characteristics of compounds in humans. The specific advantages and disadvantages of these models should be carefully considered when using them for studies in drug discovery and development. Here, an overview on the corresponding genetically humanized and chimeric liver humanized mouse models described to date is provided and illustrated with examples of their utility in drug metabolism and toxicity studies. We compare the strength and weaknesses of the two different approaches, give guidance for the selection of the appropriate model for various applications and discuss future trends and perspectives.
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Affiliation(s)
| | - Ian D Wilson
- Imperial College London, South Kensington, London SW7 2AZ, UK.
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Foster JR, Lund G, Sapelnikova S, Tyrrell DL, Kneteman NM. Chimeric rodents with humanized liver: bridging the preclinical/clinical trial gap in ADME/toxicity studies. Xenobiotica 2013; 44:109-22. [DOI: 10.3109/00498254.2013.867553] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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4
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Tachibana A, Tateno C, Yoshizato K. Repopulation of the immunosuppressed retrorsine-treated infant rat liver with human hepatocytes. Xenotransplantation 2013; 20:227-38. [PMID: 23683097 DOI: 10.1111/xen.12037] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 04/09/2013] [Indexed: 12/13/2022]
Abstract
BACKGROUND We previously generated humanized chimeric mice by transplanting h-hepatocytes into the livers of the diseased-liver transgenic mouse model with immunodeficient background. These mice with livers mostly replaced by human (h) hepatocytes have been proved to be useful for research on drug metabolism and toxicity and on intrahepatic pathogens such as hepatitis. However, their small body size prohibited collecting sufficient biological samples and made surgical manipulation difficult, which motivated us to produce humanized larger animal(s) bearing h-hepatocytes. METHODS Fischer 344 (F344) rats at 2 weeks of age were administrated with hepatotoxin retrorsine (RS) and then transplanted with syngeneic F344 rat (r)- or h-hepatocytes via the portal vein. The hosts were injected daily with FK506 immunosuppressant. The livers were harvested periodically for determining donor-cell replacement ratios and compared with those of the humanized chimeric mice, and liver-specific mRNA and protein expressions by immunohistochemistry and reverse-transcription PCR. RESULTS RS treatment of infant rats inhibited hepatocyte proliferation, resulting in decreased liver weight and megalocytic changes in hepatocytes. R-hepatocytes transplanted into RS-treated rats engrafted into and repopulated the liver at ratios of 16.4 ± 6.7% and 48.3 ± 29.3% at 3 and 6 weeks after transplantation, respectively. H-hepatocytes also engrafted into the rat liver and showed a repopulation ratio of 2.5 ± 1.5% at 3 weeks post-transplantation, which was comparable to the ratio in the humanized chimeric mouse model at least until 3 weeks. Propagated h-hepatocytes in the rat liver expressed hepatocyte-specific mRNA and proteins at least 3 weeks after transplantation. CONCLUSIONS Xenogeneic hepatocytes were able to engraft rat liver and grow well therein for at least 3 weeks post-transplantation in rats when immunosuppression was combined appropriately with liver injury at comparable levels to the well-characterized humanized chimeric mouse model.
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Affiliation(s)
- Asato Tachibana
- Yoshizato Project, Cooperative Link of Unique Science and Technology for Economy Revitalization (CLUSTER), Hiroshima Prefectural Institute of Industrial Science and Technology, Higashihiroshima, Hiroshima, Japan
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Brezillon N, Kremsdorf D, Weiss MC. Cell therapy for the diseased liver: from stem cell biology to novel models for hepatotropic human pathogens. Dis Model Mech 2009; 1:113-30. [PMID: 19048074 DOI: 10.1242/dmm.000463] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
It has long been known that hepatocytes possess the potential to replicate through many cell generations because regeneration can be achieved in rodents after serial two-thirds hepatectomy. It has taken considerable time and effort to harness this potential, with liver regeneration models involving hepatocyte transplantation developing over the past 15 years. This review will describe the experiments that have established the models and methodology for liver repopulation, and the use of cells other than adult hepatocytes in liver repopulation, including hepatic cell lines and hematopoietic, cord blood, hepatic and embryonic stem cells. Emphasis will be placed on the characteristics of the models and how they can influence the outcome of the experiments. Finally, an account of the development of murine models that are competent to accept human hepatocytes is provided. In these models, liver deficiencies are induced in immunodeficient mice, where healthy human cells have a selective advantage. These mice with humanized livers provide a powerful new experimental tool for the study of human hepatotropic pathogens.
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Affiliation(s)
- Nicolas Brezillon
- INSERM, U845, Pathogenèse des Hépatites Virales B et Immunothérapie, Paris 75015, France
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6
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Igarashi Y, Tateno C, Tanaka Y, Tachibana A, Utoh R, Kataoka M, Ohdan H, Asahara T, Yoshizato K. Engraftment of human hepatocytes in the livers of rats bearing bone marrow reconstructed with immunodeficient mouse bone marrow cells. Xenotransplantation 2009; 15:235-45. [PMID: 18957046 DOI: 10.1111/j.1399-3089.2008.00483.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Previously, we created, a chimeric mouse (humanized mouse), a severe combined immunodeficiency (SCID) mouse whose liver was >90% repopulated with human (h)-hepatocytes, which are useful for the testing of drug metabolism and toxicity, as well as a hepatitis B virus and hepatitis C virus-susceptible animal model. However, their small body size and small total blood volume limited the utilization for analytical purposes, which led us to develop a method to create a chimeric rat bearing h-hepatocyte-repopulated liver. METHODS F344 nude rats devoid of T cells were irradiated with X-rays and injected with bone marrow cells (BMCs) from SCID mice (m(SCID)). The rate of replacement with m(SCID)-BMCs was evaluated by two-color flow cytometry analysis of peripheral blood mononuclear cells (PBMCs). After m(SCID)-BMCs repopulated the host bone marrow (BM), the rats were treated with retrorsine, partially hepatectomized (PHx), and transplanted with 5 x 10(6) h-hepatocytes isolated from the chimeric mice. h-Albumin (h-Alb) concentrations in the host blood and the expression levels of protein and mRNA of hepatocyte differentiation markers in the h-hepatocytes were evaluated by ELISA, immunostaining, and reverse transcription-PCR, respectively. RESULTS The m(SCID)-BMCs successfully repopulated the rats, the percentage of mouse cells reaching 94% among host (r(nudeF344)) PBMCs at 4 weeks after m-BMC transplantation. h-Hepatocytes isolated from the chimeric mice were transplanted to the liver of the m(SCID)-BMC-repopulated rats. The engrafted h-hepatocytes expressed h-Alb and h-cytochrome P450 (CYP) subtypes and survived showing normal phenotypes until at least 3 weeks post-h-hepatocytes transplantation (h-HPCT). However, the blood concentrations of h-Alb declined at 4 weeks post-HPCT, concomitant with the emergence of both r(nudeF344)- and m(SCID)-macrophages, suggesting the rejection of h-hepatocytes due to the activation of macrophages. CONCLUSION We developed a novel method to create a rat that bears the liver engrafted with h-hepatocytes, utilizing a rat with the BM composed of m(SCID)-BMCs as a host. This h-hepatocyte-bearing rat will be a valuable model for studying the immunologic mechanisms involved in xenogeneic transplantation and for generating rats with higher rates of repopulation with h-hepatocytes.
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Affiliation(s)
- Yuka Igarashi
- Department of Surgery, Division of Frontier Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, Higashi-Hiroshima, Japan
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7
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Lin H, Mao Q, Wang YM, Jiang L. Proliferation of L02 human hepatocytes in tolerized genetically immunocompetent rats. World J Gastroenterol 2008; 14:2329-37. [PMID: 18416458 PMCID: PMC2705086 DOI: 10.3748/wjg.14.2329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate whether human hepatocytes could proliferate after transplantation to normal immunocompetent rats treated with 2-acetaminofluorene or Retrorsine and partial hepatectomy.
METHODS: L02 hepatocyte-tolerant Sprague-Dawley rats were injected with Retrorsine, 2-acetaminofluorene or normal saline. L02 hepatocytes were then transplanted via the spleen. Human albumin and its mRNA, specific proliferating cell nuclear antigen (PCNA), L02 hepatocyte dynamic distribution, number density and area density of PCNA-positive cells in the liver were determined.
RESULTS: All the examined indicators were not significantly different between the rats treated with 2-acetaminofluorene and normal saline, which was not the case with rats treated with Retrorsine. A dynamic distribution of L02 hepatocytes in the rat liver was detected from wk 1 to mo 6 after transplantation in the Retrorsine group and from wk 1 to 10 in the 2-acetaminofluorene group. Human albumin and its mRNA were detected from wk 2 to mo 6 in the Retrorsine group and from wk 1 to 8 in the 2-acetaminofluorene group. Specific human PCNA was detected in the rat liver from wk 2 to mo 6 in the Retrorsine group and from wk 2 to 6 in the 2-acetaminofluorene group. Human albumin and its mRNA contents as well as the number of PCNA positive cells reached a peak at wk 4.
CONCLUSION: L02 human hepatocytes could not proliferate significiantly after transplantation to the normal, immunocompetent rats treated with 2-acetaminofluorene. L02 human hepatocytes can survive for 10 wk after transplantation and express human albumin for 8 wk. L02 human hepatocytes can proliferate and express human albumin for 6 mo after transplantation to the rats treated with Retrorsine. The chimeric L02 human hepatocytes, which then underwent transplantation into tolerant rats, were normal in morphogenesis, biochemistry and function.
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Dandri M, Volz TK, Lütgehetmann M, Petersen J. Animal models for the study of HBV replication and its variants. J Clin Virol 2005; 34 Suppl 1:S54-62. [PMID: 16461225 DOI: 10.1016/s1386-6532(05)80011-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Enormous progresses in hepatitis B virus research have been made through the identification of avian and mammalian HBV related viruses, which offer ample opportunities for studies in naturally occurring hosts. However, none of these natural hosts belongs to the commonly used laboratory animals, and the development of various mouse strains carrying HBV transgenes offered unique opportunities to investigate some mechanisms of viral pathogenesis. Furthermore, the need to perform infection studies in a system harbouring HBV-permissive hepatocytes has lately led researchers to create new challenging human mouse chimera models of HBV infection. In this review, we will overview the type of animal models currently available in hepadnavirus research.
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Affiliation(s)
- M Dandri
- Department of Medicine, University Hospital Eppendorf University of Hamburg, Martinistr 52, D-20246 Hamburg, Germany
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9
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N/A, 毛 青, 王 宇. N/A. Shijie Huaren Xiaohua Zazhi 2005; 13:1373-1376. [DOI: 10.11569/wcjd.v13.i12.1373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/26/2023] Open
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10
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Wu GY, Konishi M, Walton CM, Olive D, Hayashi K, Wu CH. A novel immunocompetent rat model of HCV infection and hepatitis. Gastroenterology 2005; 128:1416-23. [PMID: 15887122 DOI: 10.1053/j.gastro.2005.03.015] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND & AIMS Hepatitis C virus (HCV) infects millions of people worldwide. Therapy is limited, and treatment does not produce a sustained response in the majority of patients. Development of new agents has been hampered by the lack of a convenient animal model. The aim of this study was to determine whether an immunocompetent rat, tolerized and transplanted with a human hepatoma cell line (Huh 7 cells), could be used to sustain an HCV infection. METHODS Fetal rats were tolerized in utero with 10(5) Huh 7 cells. One day after birth, rats were transplanted with 5 x 10(6) Huh 7 cells and, a week later, inoculated with HCV, genotype 1. RESULTS In tolerized, transplanted, and HCV-infected rats, Huh 7 cells were found in the liver, and HCV viral replication was detected by the presence of negative strand HCV RNA. HCV levels in serum were measured at 11,000 copies/mL at week 4, peaked at 22,500 copies/mL by week 12. In tolerized, transplanted, inoculated rats, but not controls, serum alanine aminotransferase (ALT) values increased to 60 IU/L by week 4 and reached a peak of approximately 120 IU/L by week 13. Histology showed foci of mononuclear infiltrates in portal and central regions. CONCLUSIONS HCV-inoculated immunocompetent rats tolerized and transplanted with Huh 7 cells support HCV gene expression, viral replication, and develop biochemical and histologic evidence of hepatitis.
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Affiliation(s)
- George Y Wu
- Department of Medicine, Division of Gastroenterology-Hepatology, University of Connecticut Health Center, Farmington 06030-1845, USA.
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11
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Yuen MF, Wong DKH, Sum SSM, Yuan HJ, Yuen JCH, Chan AOO, Wong BCY, Lai CL. Effect of lamivudine therapy on the serum covalently closed-circular (ccc) DNA of chronic hepatitis B infection. Am J Gastroenterol 2005; 100:1099-103. [PMID: 15842584 DOI: 10.1111/j.1572-0241.2005.41530.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To determine the effect of 1-yr lamivudine treatment on serum covalently closed-circular DNA (cccDNA) level. PATIENTS AND METHOD Serum total HBV DNA and cccDNA levels at baseline, week 24, and week 52 were measured in 82 lamivudine-treated patients, 17 of whom received 1-yr placebo and acted as controls. RESULTS There was a significant reduction in the cccDNA levels from baseline (median 3.0 x 10(6) copies/ml) to week 24 (33,476 copies/ml) and week 52 (48,694 copies/ml) (p < 0.001 for both). The median reduction in cccDNA level at week 24 and 52 were 2.21 and 2.12 logs, respectively, which were significantly greater than those of controls (0.31 log, p < 0.001; 0.2 log, p < 0.001, respectively). Fifteen patients (18.3%) developed YMDD mutations by week 52. Compared to patients without YMDD mutations, patients with YMDD mutations had significantly less median reduction of total HBV DNA level (4.44 vs 3.65 logs, respectively, p= 0.02) and cccDNA level (2.27 vs 1.65 logs, respectively, p= 0.016) at week 24 and significantly less median reduction of cccDNA at week 52 (2.35 vs 0.8 logs respectively, p < 0.001). CONCLUSIONS One-year lamivudine treatment decreased serum cccDNA level by 2 logs. The chance of YMDD mutations at week 52 was related to the magnitude of viral suppression at week 24.
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Affiliation(s)
- Man-Fung Yuen
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
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12
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Guha C, Lee SW, Chowdhury NR, Chowdhury JR. Cell culture models and animal models of viral hepatitis. Part II: hepatitis C. Lab Anim (NY) 2005; 34:39-47. [PMID: 15685191 DOI: 10.1038/laban0205-39] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2003] [Accepted: 12/16/2004] [Indexed: 12/25/2022]
Abstract
The lack of a preventive vaccine, coupled with common unresponsiveness to treatment and coinfection with HIV, has made HCV a major threat to public health. The authors review in vitro and in vivo models that are being used to study HCV and to develop new treatments and preventive measures.
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Affiliation(s)
- Chandan Guha
- Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461, USA
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Turrini P, Monego G, Gonzalez J, Cicuzza S, Bonanno G, Zelano G, Rosenthal N, Paonessa G, Laufer R, Padron J. Human hepatocytes in mice receiving pre-immune injection with human cord blood cells. Biochem Biophys Res Commun 2005; 326:66-73. [PMID: 15567153 DOI: 10.1016/j.bbrc.2004.10.204] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2004] [Indexed: 01/02/2023]
Abstract
It is well established that certain subpopulations of human adult stem cells can generate hepatocyte-like cells when transplanted into adult immunosuppressed mice. In the present study, we wanted to explore whether xeno-transplantation of human cord blood CD34(+) (hCBCD34(+)) cells during pre-immune stages of development in immunocompetent mice might also lead to human-mouse liver chimerism. Freshly isolated hCBCD34(+) cells were xeno-transplanted into non-immunosuppressed mice by both intra-blastocyst and intra-fetal injections. One and four weeks after birth, immunostaining for different human-specific hepatocyte markers: human hepatocyte-specific antigen, human serum albumin, and human alpha-1-antitrypsin indicated the presence of human hepatocyte-like cells in the livers of transplanted animals. Detection of human albumin mRNA further corroborated the development of pre-immune human-mouse chimeras. The current report, besides providing new evidence of the potential of hCBCD34(+) cells to generate human hepatocyte-like cells, suggests novel strategies for generating immunocompetent mice harboring humanized liver.
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Affiliation(s)
- Paolo Turrini
- Pharmacology Department, Istituto di Ricerca di Biologia Molecolare "P.Angeletti", Merck Sharp and Dohme Research Laboratories, Rome, Italy
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Guha C, Mohan S, Roy-Chowdhury N, Roy-Chowdhury J. Cell culture and animal models of viral hepatitis. Part I: hepatitis B. Lab Anim (NY) 2004; 33:37-46. [PMID: 15224117 DOI: 10.1038/laban0704-37] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2003] [Accepted: 02/25/2004] [Indexed: 12/19/2022]
Abstract
Despite the existence of a preventative vaccine, HBV represents a substantial threat to public health, suggesting the need for research to develop new treatments to combat the disease. The authors review the available in vitro and in vivo models, including recently developed transgenic and chimeric mouse models.
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Affiliation(s)
- Chandan Guha
- Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY, USA
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15
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Wong DKH, Yuen MF, Yuan H, Sum SSM, Hui CK, Hall J, Lai CL. Quantitation of covalently closed circular hepatitis B virus DNA in chronic hepatitis B patients. Hepatology 2004; 40:727-37. [PMID: 15349913 DOI: 10.1002/hep.20353] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This study examined a signal amplification assay, the Invader assay, for the quantitation of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) in liver biopsies and sera. DNA was extracted from liver biopsy and serum samples were collected from 16 hepatitis B e antigen (HBeAg)-positive and 36 antibody-to-HBeAg-positive (anti-HBe-positive) chronic hepatitis B patients. The amount of total HBV DNA and cccDNA was measured using the Invader assay. Anti-HBe-positive patients had lower median total intrahepatic HBV DNA (P < .001) and intrahepatic cccDNA levels (P = .001) than HBeAg-positive patients. Intrahepatic cccDNA correlated positively with the total intrahepatic HBV DNA (r = 0.950, P < .001). However, the proportion of intrahepatic HBV DNA in the form of cccDNA was inversely related to the amount of total intrahepatic HBV DNA (r = -0.822, P < .001). A small amount of cccDNA was detected in 39 of 52 (75%) serum samples. Anti-HBe-positive patients had lower median serum cccDNA levels than HBeAg-positive patients (P = .002). Serum HBV DNA correlated positively with intrahepatic total HBV DNA (r = 0.778, P < .001) and intrahepatic cccDNA (r = 0.481, P = .002). In conclusion, the Invader assay is a reliable assay for the quantitation of cccDNA. Serum and intrahepatic total HBV DNA and cccDNA levels become lower as the disease progresses from HBeAg-positive to anti-HBe-positive phase, with cccDNA becoming the predominant form of intrahepatic HBV DNA.
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Affiliation(s)
- Danny Ka-Ho Wong
- Division of Gastroenterology and Hepatology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
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Liu MC, Yu M, Zhang NL, Gong WB, Wang Y, Piao WH, Wang QH, Wang GQ. Dynamic analysis of hepatitis B virus DNA and its antigens in 2.2.15 cells. J Viral Hepat 2004; 11:124-9. [PMID: 14996346 DOI: 10.1046/j.1365-2893.2003.00485.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The 2.2.15 cells-derived from HepG2 cells transfected with a plasmid containing hepatitis B virus (HBV) DNA secrete surface antigen (HBsAg) particles, nucleocapsids and virions (Proc Natl Acad Sci U S A 1987; 84: 1005-1009). The latter elicit acute hepatitis in chimpanzees (Proc Natl Acad Sci U S A 1987; 84: 4641-4644). We studied the presence of intracellular and extracellular HBV covalently closed circular (ccc) DNA in this culture system by polymerase chain reaction (PCR), kinetically analysed HBsAg and hepatitis B e antigen (HBeAg) released in the culture media by quantitative enzyme-linked immunosorbent assay and quantitated by real-time PCR but HBV DNA from intracellular and extracellular HBV-DNA. HBV cccDNA was found both intracellularly and extracellularly. A significant correlation was seen between the extracellular HBV DNA levels and virus antigens (r = 0.833; P = 0.01 and r = 0.939; P < 0.01 for HBsAg and HBeAg, respectively), whereas there was no statistical correlation between intracellular HBV DNA levels and virus antigen levels (r = 0.024; P = 0.955 and r = 0.177; P = 0.625 for HBsAg and HBeAg, respectively). These data would be valuable in studies of the HBV life cycle and of potential anti-viral agents.
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Affiliation(s)
- M-C Liu
- Department of Infectious Diseases, First Hospital of Peking University, Beijing, China
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Abstract
Potent inhibition of endogenous gene expression by RNA interference has been achieved by using sequence-specific posttranscriptional gene silencing through the action of small interfering RNA molecules (siRNA). In these reports, the natural function of genes could be deduced through the ensuing loss of function. Based on the extraordinary effectiveness in silencing endogenous genes, we wondered whether siRNA could be applied against viral replication in a hepatitis B virus (HBV) model using HBV-specific siRNA. To test this idea, HepG2 2.2.15, a human hepatoblastoma cell line that constitutively produces infectious HBV particles, was transfected with HBV-specific siRNAs and controls. HBV surface antigen (HBsAg) secretion into culture media was inhibited by 78%, 67%, and 42% with siRNA against the polyadenylation (PA), precore (PreC), and surface (S) regions, respectively, compared with controls as detected by enzyme-linked immunosorbent assay. After exposure to HBVPA siRNA, Northern blot analysis showed that HBV pregenomic RNA levels were decreased by 72%, and levels of HBV RNA containing the polyadenylation signal sequence were suppressed by 86%, as detected by RNase protection assay. Levels of HBV core-associated DNA, a replication intermediate, also decreased by 71%. Immunocytochemistry revealed that 30% to 40% of the cells transfected with HBVPA siRNA were completely negative for detectable HBsAg levels. Controls consisting of treatment with HBV-specific siRNA alone, lipofection reagent alone, or random double-stranded RNA (dsRNA) lipofection complex failed to decrease HBV surface antigen, HBV messenger RNA (mRNA), or core-associated HBV-DNA levels. In conclusion, siRNA inhibits hepatitis B viral replication in a cell culture system. Future studies are needed to explore the specific delivery of siRNA to liver cells in vivo and the applicability of this approach.
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Affiliation(s)
- Masayoshi Konishi
- Department of Medicine, Division of Gastroenterology-Hepatology, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030-1845, USA
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Wu CH, Ouyang EC, Walton C, Promrat K, Forouhar F, Wu GY. Hepatitis B virus infection of transplanted human hepatocytes causes a biochemical and histological hepatitis in immunocompetent rats. World J Gastroenterol 2003; 9:978-83. [PMID: 12717842 PMCID: PMC4611409 DOI: 10.3748/wjg.v9.i5.978] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To characterize the host response to hepatitis B virus (HBV) infection in human hepatocytes transplanted into immunocompetent rodent rats tolerized by, and transplanted with primary human hepatocytes.
METHODS: One week after the transplantation, rats were inoculated with HBV, and viral gene expression, replication, and host response was monitored.
RESULTS: HBV DNA was detectable in serum for at least 60 days. HBsAg levels rose steadily for 3 weeks post-inoculation and then plateaued at a level of about 0.6 pg/ml. HBV RNA was also found in liver at levels that remained constant through the time course. Immunofluorescence revealed clusters of hepatocytes that stained positive for HBcAg. The presence of HBV covalently closed circular DNA (cccDNA) in liver was demonstrated using nuclease digestion of single-stranded DNA followed by PCR. Serum ALT levels rose and reached a peak level of 180 IU/L on day 18, but remained elevated for 60 days. Histology revealed a progressive predominantly mononuclear lobular hepatitis.
CONCLUSION: These data indicate that human hepatocytes transplanted into rats rendered tolerant to these cells, when infected by HBV, results in biochemical as well as histological evidence of hepatitis that accompanies viral gene expression, and DNA replication.
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Affiliation(s)
- Catherine H Wu
- Department of Medicine, Division of Gastroenterology-Hepatology, University of Connecticut Health Center, , Farmington, CT 06030-1845, USA.
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Bocharov G, Klenerman P, Ehl S. Modelling the dynamics of LCMV infection in mice: II. Compartmental structure and immunopathology. J Theor Biol 2003; 221:349-78. [PMID: 12642113 DOI: 10.1006/jtbi.2003.3180] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In this study, we develop a mathematical model for analysis of the compartmental aspects and immunopathology of lymphocytic choriomeningitis virus (LCMV) infection in mice. We used sets of original and published data on systemic (extrasplenic) virus distribution to estimate the parameters of virus growth and elimination for spleen and other anatomical compartments, such as the liver, kidney, thymus and lung as well as transfer rates between blood and the above organs. A mathematical model quantitatively integrating the virus distribution kinetics in the host, the specific cytotoxic T lymphocyte (CTL) response in spleen and the re-circulation of effector CTL between spleen, blood and liver is advanced to describe the CTL-mediated immunopathology (hepatitis) in mice infected with LCMV. For intravenous and "peripheral" routes of infection we examine the severity of the liver disease, as a function of the virus dose and the host's immune status characterized by the numbers of precursor and/or cytolytic effector CTL. The model is used to predict the efficacy of protection against virus persistence and disease in a localized viral infection as a function of the composition of CTL population. The modelling analysis suggests quantitative demands to CTL memory for maximal protection against a wide range of doses of infection with a primarily peripheral site of virus replication without the risk of favoring immunopathology. It specifies objectives for CTL vaccination to ensure virus elimination with minimal immunopathology vs. vaccination for disease.
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Affiliation(s)
- Gennady Bocharov
- Institute of Numerical Mathematics, Russian Academy of Sciences, Moscow, Russia
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