Previous Article | Next Article 
Journal of Virology, January 2005, p. 592-596, Vol. 79, No. 1
0022-538X/05/$08.00+0 doi:10.1128/JVI.79.1.592-596.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
Nonhepatic Cell Lines HeLa and 293 Support Efficient Replication of the Hepatitis C Virus Genotype 2a Subgenomic Replicon
Takanobu Kato,1,2
Tomoko Date,1
Michiko Miyamoto,1
Zijiang Zhao,1,3
Masashi Mizokami,2 and
Takaji Wakita1*
Department of Microbiology, Tokyo Metropolitan Institute for Neuroscience, Tokyo,1
Department of Clinical Molecular Informative Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan,2
Institute of Virology, Chinese Academy of Preventive Medicine, Beijing, People's Republic of China3
Received 17 May 2004/
Accepted 13 August 2004

ABSTRACT
The hepatitis C virus (HCV) genotype 2a subgenomic replicon
can replicate in two human non-hepatocyte-derived cell lines,
HeLa and 293, with in vitro-transcribed replicon RNA. Sequencing
analysis revealed that mutations in HCV-derived regions were
not essential for replication in these cells, as some clones
displayed no mutations.

TEXT
Hepatitis C virus (HCV) was first identified as a causative
agent of posttransfusion hepatitis in 1989 (
4). The virus is
considered hepatotropic and is known to cause liver diseases
such as acute or chronic hepatitis, cirrhosis, and hepatocellular
carcinoma (
11,
16,
17,
21). HCV has been detected not only in
liver, but also in peripheral blood mononuclear cells and dendritic
cells (
7,
12,
19). However, other tissue tropisms and their
regulatory factors have yet to be fully elucidated. This lack
of progress in the investigations regarding the virus is primarily
attributable to a lack of efficient cell culture systems and
small animal models of infection. As an important step toward
overcoming this disadvantage, a subgenomic HCV RNA replicon
system has been developed (
18). This replicon system contains
the HCV internal ribosome entry site (IRES), which directs expression
of the G418 selectable marker,
neor, and encephalomyocarditis
virus (EMCV) IRES directs the expression of HCV nonstructural
(NS) proteins NS3 to NS5B. This enabled assessment of HCV replication
in cultured cells. Functional replicons have previously been
reported only for genotype 1, and efficient replications of
these replicons have been accomplished only in limited human
hepatocyte-derived cell lines (
2,
3,
9). Attempts to evaluate
replication of the HCV replicon in non-hepatocyte-derived cell
lines have been made previously (
1,
23). Some of these attempts
seemed to have succeeded, but efficient replicon replication
in nonhepatic cells has not been achieved by synthetic RNA transfection,
and other experimental procedures have been required (
1,
23).
We developed a new HCV replicon system using an HCV genotype
2a clone from a patient with fulminant hepatitis (
15). This
replicon system provided higher colony formation efficiency
and robust replication, not only in Huh7 cells but also in HepG2
and IMY-N9 cells (
5,
15), which were established by fusing human
primary cultured hepatocytes and HepG2 cells (
13). The present
study examined whether this replicon, the JFH-1 replicon, can
replicate in two non-hepatocyte-derived cell lines: HeLa cells
established from human cervical carcinoma (
6) and 293 cells
established from human embryonic kidney (
8).
The HCV genotype 2a clone, JFH-1, was isolated from a patient with fulminant hepatitis, and genotype 2a HCV replicon constructs were built with this clone as reported previously (14, 15). After transfection of RNAs transcribed from the linearized pSGR-JFH1 (DDBJ/EMBL/GenBank accession no. AB114136) into HeLa and 293 cells, transfected cells were cultured for 3 weeks with G418 (Nacalai Tesque, Kyoto, Japan) at working concentrations of 0.8 mg/ml for HeLa and 293 cells and 1.0 mg/ml for Huh7 cells. Visible colonies were observed 3 weeks later in all three transfected cell lines (Fig. 1). Based on three independent assays, colony formation efficiency was lower in HeLa cells, at (5.83 ± 3.18) x103 CFU/µg of RNA, than in Huh7 cells, at (5.32 ± 5.02) x 104 CFU/µg of RNA (15). Colony formation efficiency was substantially lower in 293 cells than in Huh7 cells, at (1.36 ± 1.11) x 102 CFU/µg of RNA. A total of nine colonies for each line were cloned from pSGR-JFH1 RNA-transfected HeLa and 293 cells and expanded for further analysis.
To estimate the correct size of replicating replicon RNA, Northern
blot analysis was performed with the nine clones from each of
the HeLa and 293 cell lines. DNA probes were synthesized from
neor and EMCV-IRES genes using the Megaprime DNA labeling system
(Amersham Pharmacia). In all clones, expected sizes of replicon
RNAs were detected using
neor and EMCV-IRES probes (Fig.
2).
The amount of replicon RNA in clones of each cell line varied
among clones, particularly in HeLa clones.
HCV NS protein expression in replicon RNA-transfected cells
was tested by Western blotting with HCV NS5A-specific polyclonal
antibody obtained by DNA immunization with JFH-1 NS5A-expressing
construct (
5,
22). In JFH-1 replicon RNA-transfected clones,
HCV-specific polyclonal antibody detected NS5A protein as major
bands of various intensities at about 56 kDa (Fig.
3). A very
faint band above the major 56-kDa band was also detected in
some lanes at around 58 kDa. As a positive control, cell lysate
from Huh7 replicon cells was also loaded on the left lane of
the gel (Fig.
3, lanes 4-1 and C6). Huh7 replicon cell 4-1 displayed
strong expression (
5; unpublished data), while C6 displayed
weak expression (
5,
15). The intensity of protein expression
in each clone displayed similar trends with regard to the amount
of replicating replicon RNA in Northern blotting.
Using recovered phase serum from a patient with acute hepatitis
C, HCV antigens in JFH-1 replicon RNA-transfected HeLa and 293
clones were also detected by immunofluorescence assay (Fig.
4). Distributions of HCV-related antigens in both replicon RNA-transfected
cell lines resembled those in Huh7, and diffuse and fine reticular
patterns with some granular cytoplasmic staining were observed.
Signal intensities of HeLa and 293 replicon cells were slightly
faint compared to Huh7 replicon cells, but signals were similarly
localized within all replicon cells (Fig.
4). No signals were
detected in untransfected parental cells. Microscopic morphologies
of replicon-containing HeLa and 293 cells were normal and similar
to the respective parental cells.
To estimate adaptive mutations in HeLa and 293 cells, replicon
RNA isolated from each clone was amplified by reverse transcription-PCR
(RT-PCR) and sequenced directly (
5,
15). Copy numbers of replicating
RNA in clones were also determined by real-time detection RT-PCR
adjusting for intracellular glyceraldehyde-3-phosphate dehydrogenase
concentrations (
20). Of the nine HeLa clones, clone 1 displayed
no mutation and clone 7 had only one synonymous mutation in
the open reading frame (ORF) of HCV for replicating RNA (Table
1). Clone 3 displayed a 1-nucleotide mutation in the 3' untranslated
region (UTR), and clone 8 displayed three synonymous mutations,
one located in the core region upstream of the
neor gene and
two in the HCV ORF. These four clones thus did not contain any
mutations resulting in changes to amino acid sequences. The
remaining five clones had one to three nonsynonymous mutations
in the HCV ORF, and mutations in the NS5a region were prevalent.
The mean number of replicon RNA copies in HeLa clones was (5.01
± 2.87)
x10
6 copies/µg of RNA (range, 8.31
x 10
5 to 1.07
x 10
7 copies/µg of RNA). These data were basically
concordant with trends for signal intensities in Northern blot
analysis. Mean replicon titers in these clones were slightly
lower than those of Huh7 cells, at (2.71 ± 2.11)
x 10
7 copies/µg of RNA (M. Miyamoto, T. Kato, T. Date, and T.
Wakita, unpublished data). The mean copy number for replicon
RNA in clones with nonsynonymous mutations in the HCV ORF (clones
2, 4, 5, 6, and 9) did not differ significantly from that of
clones without nonsynonymous mutations (clones 1, 3, 7, and
8) [(6.03 ± 3.05)
x 10
6 versus (3.74 ± 2.38)
x 10
6 copies/µg of RNA;
P = 0.261].
For 293 cell clones, surprisingly, eight of the nine clones
displayed no mutation or only one synonymous mutation (Table
2). The remaining clone (clone 6) had one nonsynonymous mutation
in the NS5a region and one synonymous mutation. The mean number
of replicon RNA copies in 293 clones was (5.30 ± 0.16)
x 10
6 copies/µg of RNA (range, 3.47
x 10
6 to 8.33
x 10
6 copies/µg of RNA). The mutation-containing clone, clone
6, showed a replicon titer close to the mean (4.38
x 10
6 copies/µg
of RNA). This mutation was thus not considered to affect replication
efficiency. Mutations previously observed in Huh7 and other
hepatocyte-derived cell lines were not detected in HeLa and
293 clones (
5,
15).
Our results show that HCV replicon can replicate efficiently
in two non-hepatocyte-derived cell lines. Colony formation efficiencies
in cell lines HeLa and 293 were lower than in Huh7, but higher
than in hepatocyte-derived cell lines HepG2 and IMY-N9 (
5,
15).
The amounts of replicating replicon RNA in HeLa and 293 cells
were comparable to those in HepG2 cells. These results indicate
that the JFH-1 replicon can replicate equally well in non-hepatocyte-
and hepatocyte-derived cell lines. Sequencing of HCV-derived
region in replicons replicating in these cells indicated that
no common mutations were observed in these cells. In HeLa clones,
five clones displayed nonsynonymous mutations and the other
four clones contained no nonsynonymous mutations in the HCV-derived
region (Table
1). Amounts of replicating replicon RNAs did not
differ between clones with or without nonsynonymous mutations.
In 293 cells, surprisingly, most replicon clones had no or only
one synonymous mutation (Table
2). As a whole, these results
indicate that the JFH-1 replicon can replicate in these cells
efficiently without cell-specific mutations and adaptive mutations
in these cells might be unnecessary. Furthermore, distributions
of HCV antigens in these cells resemble those in Huh7 cells
(Fig.
4). Taken together, cell tropism of HCV does not appear
to be regulated by cellular factors preventing replication or
requiring cell-specific mutation.
To further characterize JFH-1 replicon-containing HeLa and 293 cells, modifications of cell growth rate were investigated. Temporal evolution of viable cell count was estimated by resazurin reduction assay using the Promega cell titer-blue cell viability assay (Promega, Madison, Wis.). Cell growth rates did not differ significantly between HeLa cells with and without replicon (Fig. 5A). In contrast, in 293 cells, the cell growth rate was slower in replicon-containing cells than in parental cells (Fig. 5B). Therefore, expression of HCV proteins or replication of the JFH-1 replicon seems to suppress cell growth in 293 cells, but this tendency was not clearly observed in HeLa cells. Interferon sensitivities of the two replicon-containing cell lines were also assessed. Administration of interferon suppressed replication of JFH-1 replicon in a dose-dependent manner in both cell lines (Fig. 6). The 50% inhibitory concentrations ranged from 0.6 to 0.8 U/ml in HeLa cells and from 2.2 to 2.4 U/ml in 293 cells. These data are consistent with previously reported interferon sensitivities of genotype 1 HeLa and 293 replicon cells (1, 10).
Differing results between previous studies and the present study
are probably attributable to the HCV clone used in replicon
construction (
1,
23). Our HCV clone, JFH-1, was isolated from
a patient with fulminant hepatitis (
14). This replicon displays
potent replication ability above that reported for clones with
adaptive mutations in their genomes (
15). This robust replication
ability enabled assessment of replication not only in Huh7 cells
but also in other cell lines. Whether this replication ability
is specifically associated with fulminant hepatitis and which
HCV region or amino acid residues are responsible for this ability
remain unclear. Further investigations are thus needed to investigate
these issues.
Our results show that nonhepatic cell lines support HCV replication. This suggests that once HCV enters a cell, replication can occur. Hepatotropism of HCV may thus be determined at the step of viral entry into the cell. Specific receptors for HCV may be expressed on the hepatocyte surface. Development of models for HCV infection appears indispensable for further clarification of this hypothesis, although no such system has yet been reported. Establishment of a full-length replicon system using the JFH-1 clone and various cell lines is thus important. When such a model system has been achieved, these two non-hepatocyte-derived cell lines may well prove instrumental in identifying HCV receptors, as these cells can support HCV replication but will not express the receptors necessary for viral hepatotropism.
In summary, the HCV genotype 2a replicon can replicate not only in hepatocytes, but also in the HeLa and 293 non-hepatocyte-derived cell lines. These results provide useful information about HCV replication and cell tropisms.

ACKNOWLEDGMENTS
We thank Satoshi Koike for helpful discussion and Kotaro Yasui
for support.
This work was partially supported by a Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science; grants from Toray Industries, Inc.; the Program for Promotion of Fundamental Studies in Health Sciences of the Organization for Pharmaceutical Safety and Research of Japan; the Research on Health Sciences focusing on Drug Innovation from the Japan Health Sciences Foundation; and The Japanese Society of Gastroenterology.

FOOTNOTES
* Corresponding author. Mailing address: Department of Microbiology, Tokyo Metropolitan Institute for Neuroscience, 2-6 Musashidai, Fuchu, Tokyo 183-8526, Japan. Phone: 81-423-25-3881. Fax: 81-423-21-8678. E-mail:
wakita{at}tmin.ac.jp.


REFERENCES
- 1 Ali, S., C. Pellerin, D. Lamarre, and G. Kukolj. 2004. Hepatitis C virus subgenomic replicons in the human embryonic kidney 293 cell line. J. Virol. 78:491-501.[Abstract/Free Full Text]
- 2 Bartenschlager, R., and V. Lohmann. 2000. Replication of hepatitis C virus. J. Gen. Virol. 81:1631-1648.[Free Full Text]
- 3 Blight, K. J., J. A. McKeating, J. Marcotrigiano, and C. M. Rice. 2003. Efficient replication of hepatitis C virus genotype 1a RNAs in cell culture. J. Virol. 77:3181-3190.[Abstract/Free Full Text]
- 4 Choo, Q. L., G. Kuo, A. J. Weiner, L. R. Overby, D. W. Bradley, and M. Houghton. 1989. Isolation of a cDNA clone derived from a blood-borne non-A, non-B viral hepatitis genome. Science 244:359-362.[Abstract/Free Full Text]
- 5 Date, T., T. Kato, M. Miyamoto, Z. Zhao, K. Yasui, M. Mizokami, and T. Wakita. 2004. Genotype 2a hepatitis C virus subgenomic replicon can replicate in HepG2 and IMY-N9 cells. J. Biol. Chem. 279:22371-22376.[Abstract/Free Full Text]
- 6 Gey, G. O., W. D. Coffman, and M. T. Kubicek. 1952. Tissue culture studies of the proliferative capacity of cervical carcinoma and normal epithelium. Cancer Res. 12:264-265.
- 7 Goutagny, N., A. Fatmi, V. De Ledinghen, F. Penin, P. Couzigou, G. Inchauspe, and C. Bain. 2003. Evidence of viral replication in circulating dendritic cells during hepatitis C virus infection. J. Infect. Dis. 187:1951-1958.[CrossRef][Medline]
- 8 Graham, F. L., J. Smiley, W. C. Russell, and R. Nairn. 1997. Characteristics of a human cell line transformed by DNA from human adenovirus type 5. J. Gen. Virol. 36:59-74.
- 9 Gu, B., A. T. Gates, O. Isken, S.-E. Behrens, and R. T. Sarisky. 2003. Replication studies using genotype 1a subgenomic hepatitis C virus replicons. J. Virol. 77:5352-5359.[Abstract/Free Full Text]
- 10 Guo, J.-T., Q. Zhu, and C. Seeger. 2003. Cytopathic and noncytopathic interferon responses in cells expressing hepatitis C virus subgenomic replicons. J. Virol. 77:10769-10779.[Abstract/Free Full Text]
- 11 Hoofnagle, J. H. 2002. Course and outcome of hepatitis C. Hepatology 36:S21-S29.[CrossRef][Medline]
- 12 Hu, Y., A. Shahidi, S. Park, D. Guilfoyle, and I. Hirshfield. 2003. Detection of extrahepatic hepatitis C virus replication by a novel, highly sensitive, single-tube nested polymerase chain reaction. Am. J. Clin. Pathol. 119:95-100.[CrossRef][Medline]
- 13 Ito, T., K. Yasui, J. Mukaigawa, A. Katsume, M. Kohara, and K. Mitamura. 2001. Acquisition of susceptibility to hepatitis C virus replication in HepG2 cells by fusion with primary human hepatocytes: establishment of a quantitative assay for hepatitis C virus infectivity in a cell culture system. Hepatology 34:566-572.[CrossRef][Medline]
- 14 Kato, T., A. Furusaka, M. Miyamoto, T. Date, K. Yasui, J. Hiramoto, K. Nagayama, T. Tanaka, and T. Wakita. 2001. Sequence analysis of hepatitis C virus isolated from a fulminant hepatitis patient. J. Med. Virol. 64:334-339.[CrossRef][Medline]
- 15 Kato, T., T. Date, M. Miyamoto, A. Furusaka, K. Tokushige, M. Mizokami, and T. Wakita. 2003. Efficient replication of the genotype 2a hepatitis C virus subgenomic replicon. Gastroenterology 125:1808-1817.[CrossRef][Medline]
- 16 Kuo, G., Q. L. Choo, H. J. Alter, G. L. Gitnick, A. G. Redeker, R. H. Purcell, T. Miyamura, J. L. Dienstag, M. J. Alter, C. E. Stevens, G. E. Tegtmeier, F. Bonino, M. Colombo, W. S. Lee, C. Kuo, K. Berger, J. R. Shuster, L. R. Overby, D. W. Bradley, and M. Houghton. 1989. An assay for circulating antibodies to a major etiologic virus of human non-A, non-B hepatitis. Science 244:362-364.[Abstract/Free Full Text]
- 17 Liang, T. J., L. J. Jeffers, K. R. Reddy, M. De Medina, I. T. Parker, H. Cheinquer, V. Idrovo, A. Rabassa, and E. R. Schiff. 1993. Viral pathogenesis of hepatocellular carcinoma in the United States. Hepatology 18:1326-1333.[CrossRef][Medline]
- 18 Lohmann, V., F. Korner, J. Koch, U. Herian, L. Theilmann, and R. Bartenschlager. 1999. Replication of subgenomic hepatitis C virus RNAs in a hepatoma cell line. Science 285:110-113.[Abstract/Free Full Text]
- 19 Nishiguchi, S., K. Fukuda, S. Shiomi, T. Takeda, T. Kuroki, M. Ogami, H. Morimoto, S. Otani, M. Sakurai, and A. Matsuhisa. 2003. Peripheral blood mononuclear cells are possible extrahepatic replication sites for hepatitis C virus. Hepatogastroenterology 50:1301-1304.[Medline]
- 20 Takeuchi, T., A. Katsume, T. Tanaka, A. Abe, K. Inoue, K. Tsukiyama-Kohara, R. Kawaguchi, S. Tanaka, and M. Kohara. 1999. Real-time detection system for quantification of hepatitis C virus genome. Gastroenterology 116:636-642.[CrossRef][Medline]
- 21 Tong, M. J., N. S. el-Farra, A. R. Reikes, and R. L. Co. 1995. Clinical outcomes after transfusion-associated hepatitis C. N. Engl. J. Med. 332:1463-1466.[Abstract/Free Full Text]
- 22 Zhao, Z., T. Wakita, and K. Yasui. 2003. Inoculation of plasmids encoding Japanese encephalitis virus PrM-E proteins with colloidal gold elicits a protective immune response in BALB/c mice. J. Virol. 77:4248-4260.[Abstract/Free Full Text]
- 23 Zhu, Q., J.-T. Guo, and C. Seeger. 2003. Replication of hepatitis C virus subgenomes in nonhepatic epithelial and mouse hepatoma cells. J. Virol. 77:9204-9210.[Abstract/Free Full Text]
Journal of Virology, January 2005, p. 592-596, Vol. 79, No. 1
0022-538X/05/$08.00+0 doi:10.1128/JVI.79.1.592-596.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Schwarz, A. K., Grove, J., Hu, K., Mee, C. J., Balfe, P., McKeating, J. A.
(2009). Hepatoma Cell Density Promotes Claudin-1 and Scavenger Receptor BI Expression and Hepatitis C Virus Internalization. J. Virol.
83: 12407-12414
[Abstract]
[Full Text]
-
Murakami, K., Kimura, T., Osaki, M., Ishii, K., Miyamura, T., Suzuki, T., Wakita, T., Shoji, I.
(2008). Virological characterization of the hepatitis C virus JFH-1 strain in lymphocytic cell lines. J. Gen. Virol.
89: 1587-1592
[Abstract]
[Full Text]
-
Yang, W., Qiu, C., Biswas, N., Jin, J., Watkins, S. C., Montelaro, R. C., Coyne, C. B., Wang, T.
(2008). Correlation of the Tight Junction-like Distribution of Claudin-1 to the Cellular Tropism of Hepatitis C Virus. J. Biol. Chem.
283: 8643-8653
[Abstract]
[Full Text]
-
Jiang, D., Guo, H., Xu, C., Chang, J., Gu, B., Wang, L., Block, T. M., Guo, J.-T.
(2008). Identification of Three Interferon-Inducible Cellular Enzymes That Inhibit the Replication of Hepatitis C Virus. J. Virol.
82: 1665-1678
[Abstract]
[Full Text]
-
Zheng, A., Yuan, F., Li, Y., Zhu, F., Hou, P., Li, J., Song, X., Ding, M., Deng, H.
(2007). Claudin-6 and Claudin-9 Function as Additional Coreceptors for Hepatitis C Virus. J. Virol.
81: 12465-12471
[Abstract]
[Full Text]
-
Tellinghuisen, T. L., Evans, M. J., von Hahn, T., You, S., Rice, C. M.
(2007). Studying Hepatitis C Virus: Making the Best of a Bad Virus. J. Virol.
81: 8853-8867
[Full Text]
-
Kusakawa, T., Shimakami, T., Kaneko, S., Yoshioka, K., Murakami, S.
(2007). Functional Interaction of Hepatitis C Virus NS5B with Nucleolin GAR Domain. J Biochem
141: 917-927
[Abstract]
[Full Text]
-
Kato, T., Matsumura, T., Heller, T., Saito, S., Sapp, R. K., Murthy, K., Wakita, T., Liang, T. J.
(2007). Production of Infectious Hepatitis C Virus of Various Genotypes in Cell Cultures. J. Virol.
81: 4405-4411
[Abstract]
[Full Text]
-
Huang, H., Sun, F., Owen, D. M., Li, W., Chen, Y., Gale, M. Jr., Ye, J.
(2007). From the Cover: Hepatitis C virus production by human hepatocytes dependent on assembly and secretion of very low-density lipoproteins. Proc. Natl. Acad. Sci. USA
104: 5848-5853
[Abstract]
[Full Text]
-
Lazaro, C. A., Chang, M., Tang, W., Campbell, J., Sullivan, D. G., Gretch, D. R., Corey, L., Coombs, R. W., Fausto, N.
(2007). Hepatitis C Virus Replication in Transfected and Serum-Infected Cultured Human Fetal Hepatocytes. Am. J. Pathol.
170: 478-489
[Abstract]
[Full Text]
-
Kapadia, S. B., Barth, H., Baumert, T., McKeating, J. A., Chisari, F. V.
(2007). Initiation of Hepatitis C Virus Infection Is Dependent on Cholesterol and Cooperativity between CD81 and Scavenger Receptor B Type I. J. Virol.
81: 374-383
[Abstract]
[Full Text]
-
Chang, K.-S., Cai, Z., Zhang, C., Sen, G. C., Williams, B. R. G., Luo, G.
(2006). Replication of Hepatitis C Virus (HCV) RNA in Mouse Embryonic Fibroblasts: Protein Kinase R (PKR)-Dependent and PKR-Independent Mechanisms for Controlling HCV RNA Replication and Mediating Interferon Activities. J. Virol.
80: 7364-7374
[Abstract]
[Full Text]
-
Shimakami, T., Honda, M., Kusakawa, T., Murata, T., Shimotohno, K., Kaneko, S., Murakami, S.
(2006). Effect of Hepatitis C Virus (HCV) NS5B-Nucleolin Interaction on HCV Replication with HCV Subgenomic Replicon. J. Virol.
80: 3332-3340
[Abstract]
[Full Text]
-
Cai, Z., Zhang, C., Chang, K.-S., Jiang, J., Ahn, B.-C., Wakita, T., Liang, T. J., Luo, G.
(2005). Robust Production of Infectious Hepatitis C Virus (HCV) from Stably HCV cDNA-Transfected Human Hepatoma Cells. J. Virol.
79: 13963-13973
[Abstract]
[Full Text]
-
Kato, T., Date, T., Miyamoto, M., Sugiyama, M., Tanaka, Y., Orito, E., Ohno, T., Sugihara, K., Hasegawa, I., Fujiwara, K., Ito, K., Ozasa, A., Mizokami, M., Wakita, T.
(2005). Detection of Anti-Hepatitis C Virus Effects of Interferon and Ribavirin by a Sensitive Replicon System. J. Clin. Microbiol.
43: 5679-5684
[Abstract]
[Full Text]
-
Targett-Adams, P., McLauchlan, J.
(2005). Development and characterization of a transient-replication assay for the genotype 2a hepatitis C virus subgenomic replicon. J. Gen. Virol.
86: 3075-3080
[Abstract]
[Full Text]
-
Windisch, M. P., Frese, M., Kaul, A., Trippler, M., Lohmann, V., Bartenschlager, R.
(2005). Dissecting the Interferon-Induced Inhibition of Hepatitis C Virus Replication by Using a Novel Host Cell Line. J. Virol.
79: 13778-13793
[Abstract]
[Full Text]
-
Jopling, C. L., Yi, M., Lancaster, A. M., Lemon, S. M., Sarnow, P.
(2005). Modulation of Hepatitis C Virus RNA Abundance by a Liver-Specific MicroRNA. Science
309: 1577-1581
[Abstract]
[Full Text]
-
Zhong, J., Gastaminza, P., Cheng, G., Kapadia, S., Kato, T., Burton, D. R., Wieland, S. F., Uprichard, S. L., Wakita, T., Chisari, F. V.
(2005). Robust hepatitis C virus infection in vitro. Proc. Natl. Acad. Sci. USA
102: 9294-9299
[Abstract]
[Full Text]