bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antibody-Mediated Targeting of an Adenovirus Vector Modified To Contain a Synthetic Immunoglobulin G-Binding Domain in the Capsid
Authors: Volpers Christoph , Thirion Christian , Biermann Volker , Hussmann Stefanie , Kewes Helmut , Dunant Patrick , von der Mark Helga , Herrmann Andreas , Kochanek Stefan , Lochmüller Hanns 
Published: January 2003

ABSTRACT

Adenovirus vectors have been targeted to different cell types by genetic modification of the capsid or by using recombinant or chemically engineered adaptor molecules. However, both genetic capsid modifications and bridging adaptors have to be specifically tailored for each particular targeting situation. Here, we present an efficient and versatile strategy allowing the direct use of monoclonal antibodies against cell surface antigens for targeting of adenovirus vectors. A synthetic 33-amino-acid immunoglobulin G (IgG)-binding domain (Z33) derived from staphylococcal protein A was inserted into the adenovirus fiber protein. The fiber retained the ability to assemble into trimers, bound IgG with high affinity (

K
d

= 2.4 nM), and was incorporated into vector particles. The transduction efficiency of the Z33-modified adenovirus vector in epidermal growth factor receptor (EGFR)-expressing cells was strongly and dose-dependently enhanced by combination with an EGFR-specific monoclonal antibody. The antibody-mediated increase in cellular transduction was abolished in the presence of competing protein A. In targeting experiments with differentiated primary human muscle cells, up to a 77-fold increase in reporter gene transfer was achieved by preincubation of the vector with monoclonal antibodies directed against neuronal cell adhesion molecule or integrin α
7
, respectively. The IgG-binding adenovirus vector holds promise for directed gene transfer to a wide variety of cell types by simply changing the target-specific antibody.
Establishment of B-Cell Lymphoma Cell Lines Persistently Infected with Hepatitis C Virus In Vivo and In Vitro: the Apoptotic Effects of Virus Infection
Authors: Sung Vicky M.-H. , Shimodaira Shigetaka , Doughty Alison L. , Picchio Gaston R. , Can Huong , Yen T. S. Benedict , Lindsay Karen L. , Levine Alexandra M. , Lai Michael M. C. 
Published: January 2003

ABSTRACT
Hepatitis C virus (HCV) is a major cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Studies of HCV replication and pathogenesis have so far been hampered by the lack of an efficient tissue culture system for propagating HCV in vitro. Although HCV is primarily a hepatotropic virus, an increasing body of evidence suggests that HCV also replicates in extrahepatic tissues in natural infection. In this study, we established a B-cell line (SB) from an HCV-infected non-Hodgkin's B-cell lymphoma. HCV RNA and proteins were detectable by RNase protection assay and immunoblotting. The cell line continuously produces infectious HCV virions in culture. The virus particles produced from the culture had a buoyant density of 1.13 to 1.15 g/ml in sucrose and could infect primary human hepatocytes, peripheral blood mononuclear cells (PBMCs), and an established B-cell line (Raji cells) in vitro. The virus from SB cells belongs to genotype 2b. Single-stranded conformational polymorphism and sequence analysis of the viral RNA quasispecies indicated that the virus present in SB cells most likely originated from the patient's spleen and had an HCV RNA quasispecies pattern distinct from that in the serum. The virus production from the infected primary hepatocytes showed cyclic variations. In addition, we have succeeded in establishing several Epstein-Barr virus-immortalized B-cell lines from PBMCs of HCV-positive patients. Two of these cell lines are positive for HCV RNA as detected by reverse transcriptase PCR and for the nonstructural protein NS3 by immunofluorescence staining. These observations unequivocally establish that HCV infects B cells in vivo and in vitro. HCV-infected cell lines show significantly enhanced apoptosis. These B-cell lines provide a reproducible cell culture system for studying the complete replication cycle and biology of HCV infections.
Nuclear Localization of the Duck Hepatitis B Virus Capsid Protein: Detection and Functional Implications of Distinct Subnuclear Bodies in a Compartment Associated with RNA Synthesis and Maturation
Authors: Mabit Hélène , Knaust Andreas , Breiner Klaus M. , Schaller Heinz 
Published: January 2003

ABSTRACT
We have reinvestigated the subcellular distribution of the duck hepatitis B virus (DHBV) core protein in infected duck hepatocytes and in transfected cells. By using indirect immunofluorescence, the protein was found to be localized not only in the cytoplasm, as described previously, but also within the cell nucleus, being concentrated in distinct, brightly staining nuclear core bodies (NCBs). In colocalization studies using confocal microscopy, the NCBs were found exclusively in the periphery of nuclear subdomains characterized as splicing factor compartments and distal to other subnuclear domains. Also relevant for their functional significance is that the NCBs formed during the establishment of virus infection, i.e., at very low overall concentrations of newly synthesized core protein, and persisted throughout all stages of infection. Moreover, a subset of NCBs colocalized with foci of pregenomic DHBV RNA present at concentrations detectable by fluorescence in situ hybridization. Taken together, these findings indicate that a minor fraction of the DHBV core protein molecules escapes the major cytoplasmic assembly pathway to accumulate in specific subnuclear domains, and they furthermore suggest that these NCBs serve a role in the synthesis and/or maturation of the DHBV RNA pregenome.
Effect of Humoral Immune Responses on Controlling Viremia during Primary Infection of Rhesus Monkeys with Simian Immunodeficiency Virus
Authors: Schmitz Jörn E. , Kuroda Marcelo J. , Santra Sampa , Simon Meredith A. , Lifton Michelle A. , Lin Wenyu , Khunkhun Rajinder , Piatak Michael , Lifson Jeffrey D. , Grosschupff Gudrun , Gelman Rebecca S. , Racz Paul , Tenner-Racz Klara , Mansfield Keith A. , Letvin Norman L. , Montefiori David C. , Reimann Keith A. 
Published: January 2003

ABSTRACTCellular immune responses mediated by CD8+lymphocytes exert efficient control of virus replication during primary simian immunodeficiency virus (SIV) infection. However, the role that antibodies may play in the early control of virus replication remains unclear. To evaluate how antibody responses may affect virus replication during primary SIVmac infection, we depleted rhesus monkeys of B cells with anti-CD20 antibody. In normal rhesus monkeys immunized with tetanus toxoid, anti-CD20 treatment and resulting depletion of B cells inhibited the generation of antitetanus antibodies, while tetanus-specific T-cell responses were preserved. During the first 4 weeks after inoculation with SIVmac251, development of SIV-specific neutralizing antibody was delayed, and titers were significantly lower in B-cell-depleted monkeys than control-antibody-treated monkeys. Despite the lower neutralizing antibody titers, the levels of plasma SIV RNA and the linear slope of the decline seen in B-cell-depleted monkeys did not differ from that observed in monkeys treated with control antibody. However, beginning at day 28 after SIV infection, the B-cell-depleted monkeys showed a significant inverse correlation between neutralizing antibody titers and plasma virus level. These results suggest that the rapid decline of peak viremia that typically occurs during the first 3 weeks of infection was not significantly affected by SIV-specific antibodies. However, the inverse correlation between neutralizing antibodies and plasma virus level during the postacute phases of infection suggests that humoral immune responses may contribute to the control of SIV replication.
In Vivo Induction of Apoptosis Correlating with Reduced Infectivity during Baculovirus Infection
Authors: Clarke Thomas E. , Clem Rollie J. 
Published: January 2003

ABSTRACT

Spodoptera frugiperda
caterpillars were infected with a mutant of
Autographa californica M
nucleopolyhedrovirus lacking the antiapoptotic
p35
gene. Viral infectivity, replication, and spread were substantially reduced compared to that of a control revertant virus. Terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling confirmed that apoptosis occurred in mutant-infected caterpillars, thus directly correlating reduced infectivity and in vivo induction of apoptosis.
Amplification of a Complete Simian Immunodeficiency Virus Genome from Fecal RNA of a Wild Chimpanzee
Authors: Santiago Mario L. , Bibollet-Ruche Frederic , Bailes Elizabeth , Kamenya Shadrack , Muller Martin N. , Lukasik Magdalena , Pusey Anne E. , Collins D. Anthony , Wrangham Richard W. , Goodall Jane , Shaw George M. , Sharp Paul M. , Hahn Beatrice H. 
Published: January 2003

ABSTRACT

Current knowledge of the genetic diversity of simian immunodeficiency virus (SIVcpz) infection of wild chimpanzees (
Pan troglodytes
) is incomplete since few isolates, mostly from captive apes from Cameroon and Gabon, have been characterized; yet this information is critical for understanding the origins of human immunodeficiency virus type 1 (HIV-1) and the circumstances leading to the HIV-1 pandemic. Here, we report the first full-length SIVcpz sequence (TAN1) from a wild chimpanzee (
Pan troglodytes schweinfurthii
) from Gombe National Park (Tanzania), which was obtained noninvasively by amplification of virion RNA from fecal samples collected under field conditions. Using reverse transcription-PCR and a combination of generic and strain-specific primers, we amplified 13 subgenomic fragments which together spanned the entire TAN1 genome (9,326 bp). Distance and phylogenetic tree analyses identified TAN1 unambiguously as a member of the HIV-1/SIVcpz group of viruses but also revealed an extraordinary degree of divergence from all previously characterized SIVcpz and HIV-1 strains. In Gag, Pol, and Env proteins, TAN1 differed from west-central African SIVcpz and HIV-1 strains on average by 36, 30, and 51% of amino acid sequences, respectively, approaching distance values typically found for SIVs from different primate species. The closest relative was SIVcpzANT, also from a
P. t. schweinfurthii
ape, which differed by 30, 25, and 44%, respectively, in these same protein sequences but clustered with TAN1 in all major coding regions in a statistically highly significant manner. These data indicate that east African chimpanzees, like those from west-central Africa, are naturally infected by SIVcpz but that their viruses comprise a second, divergent SIVcpz lineage which appears to have evolved in relative isolation for an extended period of time. Our data also demonstrate that noninvasive molecular epidemiological studies of SIVcpz in wild chimpanzees are feasible and that such an approach may prove essential for unraveling the evolutionary history of SIVcpz/HIV-1 as well as that of other pathogens naturally infecting wild primate populations.
CD154 Blockade Results in Transient Reduction in Theiler's Murine Encephalomyelitis Virus-Induced Demyelinating Disease
Authors: Howard Laurence M. , Neville Katherine L. , Haynes Lia M. , Dal Canto Mauro C. , Miller Stephen D. 
Published: January 2003

ABSTRACTTransient CD154 blockade at the onset of Theiler's murine encephalomyelitis virus-induced demyelinating disease ameliorated disease progression for 80 days, reduced immune cell infiltration, and transiently increased viral loads in the central nervous system. Peripheral antiviral and autoimmune T-cell responses were normal, and disease severity returned to control levels by day 120.
Protein Phosphatase 2A Enhances Activation of Human Immunodeficiency Virus Type 1 by Phorbol Myristate Acetate
Authors: Faulkner Neil E. , Lane Brian R. , Bock Paul J. , Markovitz David M. 
Published: January 2003

ABSTRACT

The viral replication rate in patients infected with human immunodeficiency virus type 1 (HIV-1) is controlled in part by regulation of the transcription of viral genes. The rate of transcription is determined by a complex interplay between cellular and viral proteins and the promoter elements found in the long terminal repeats. Protein phosphatase 2A (PP2A) is a phosphoprotein that plays important roles in the regulation of signal transduction and cell growth. In this report, we demonstrate that overexpression of the catalytic subunit of protein phosphatase 2A (PP2Ac) increases the basal activity of the HIV-1 promoter and, especially, enhances the promoter's response to the protein kinase C (PKC) activator 12-
O
-tetradecanoyl phorbol-13-acetate (PMA). Additionally, ectopic PP2Ac enhances activation of HIV-1 provirus by PMA. Okadaic acid, a potent inhibitor of PP2A, markedly reduces both HIV-1 enhancer and proviral activation. Fostriecin, a PP2A inhibitor which has been used as an antineoplastic agent in clinical trials, is also able to inhibit PMA-stimulated HIV-1 proviral activation. These observations demonstrate a role for the important cellular phosphatase PP2A in HIV-1 transcription and replication and also suggest that PKC can potentiate the activity of PP2A. PP2A is a potential target for therapeutic intervention in patients infected with HIV-1.
Duck Hepatitis B Virus Virion Secretion Requires a Double-Stranded DNA Genome
Authors: Perlman David , Hu Jianming 
Published: January 2003

ABSTRACT
Hepatitis B virus assembly begins with the packaging of an RNA pregenome into intracellular nucleocapsids, with subsequent reverse transcription within these nucleocapsids converting the RNA into a characteristic, partially double-stranded DNA, which, alone, is found in enveloped extracellular virions as the viral genome. Using a synchronized replication system for the duck hepatitis B virus, together with a stringent two-step assay for virion secretion, we demonstrate that this selective genome secretion results from an intrinsic secretion competence gained only by the nucleocapsids at the late stage of reverse transcription.
In Vitro RNA Replication Directed by Replicase Complexes Isolated from the Subgenomic Replicon Cells of Hepatitis C Virus
Authors: Lai Vicky C. H. , Dempsey Shannon , Lau Johnson Y. N. , Hong Zhi , Zhong Weidong 
Published: January 2003

ABSTRACT

Replication of hepatitis C virus (HCV) RNA in virus-infected cells is believed to be catalyzed by viral replicase complexes (RCs), which may consist of various virally encoded nonstructural proteins and host factors. In this study, we characterized the RC activity of a crude membrane fraction isolated from HCV subgenomic replicon cells. The RC preparation was able to use endogenous replicon RNA as a template to synthesize both single-stranded (ss) and double-stranded (ds) RNA products. Divalent cations (Mg
2+
and Mn
2+
) showed different effects on RNA synthesis. Mg
2+
ions stimulated the synthesis of ss RNA but had little effect on the synthesis of ds RNA. In contrast, Mn
2+
ions enhanced primarily the synthesis of ds RNA. Interestingly, ss RNA could be synthesized under certain conditions in the absence of ds RNA, and vice versa, suggesting that the ss and ds RNA were derived either from different forms of replicative intermediates or from different RCs. Pulse-chase analysis showed that radioactivity incorporated into the ss RNA was chased into the ds RNA and other larger RNA species. This observation indicated that the newly synthesized ss RNA could serve as a template for a further round of RNA synthesis. Finally, 3′ deoxyribonucleoside triphosphates were able to inhibit RNA synthesis in this cell-free system, presumably through chain termination, with 3′ dGTP having the highest potency. Establishment of the replicase assay will facilitate the identification and evaluation of potential inhibitors that would act against the entire RC of HCV.
Randomized Trial Comparing Six Versus Three Cycles of Epirubicin-Based Adjuvant Chemotherapy in Premenopausal, Node-Positive Breast Cancer Patients: 10-Year Follow-Up Results of the French Adjuvant Study Group 01 Trial
Authors: Fumoleau Pierre , Kerbrat Pierre , Romestaing Pascale , Fargeot Pierre , Brémond Alain , Namer Moïse , Schraub Simon , Goudier Marie-Jo , Mihura Jeanne , Monnier Alain , Clavère Pierre , Serin Daniel , Seffert Philippe , Pourny Christiane , Facchini Thomas , Jacquin Jean-Philippe , Sztermer Jean-François , Datchary Jean , Ramos René , Luporsi Elisabeth 
Published: January 2003

Purpose: To evaluate the duration and dose intensity of epirubicin-based regimens in premenopausal patients with lymph node-positive breast cancer. Patients and Methods: Between 1986 and 1990, 621 patients with operable breast cancer were randomly assigned to receive fluorouracil (Roche SA, Basel, Switzerland) 500 mg/m2, epirubicin (Pharmacia SA, Milan, Italy) 50 mg/m2, and cyclophosphamide (Asta Medica AG, Frankfurt, Germany) 500 mg/m2 every 21 days (FEC 50) for six cycles (6 FEC 50); FEC 50 for three cycles (3 FEC 50); or the same regimen with epirubicin 75 mg/m2 (FEC 75) for three cycles (3 FEC 75). All patients in the three arms received chest wall irradiation at the end of the third cycle. Results: After a 131-month median follow-up, the 10-year disease-free survival (DFS) was 53.4%, 42.5%, and 43.6% (P = .05) in the three arms, respectively. Pairwise comparisons demonstrate that 6 FEC 50 was superior both to 3 FEC 50 (P = .02) and to 3 FEC 75 (P = .05). The 10-year overall survival (OS) for the 6 FEC 50 arm was 64.3%, for the 3 FEC 50 arm it was 56.6%, and for the 3 FEC 75 arm, it was 59.7% (P = .25), respectively. Pairwise comparisons demonstrate that 6 FEC 50 was more effective than 3 FEC 50 (P = .10). Cox regression analysis demonstrates that OS was significantly better in the 6 FEC 50 than in the 3 FEC 50 arm (P = .046). No severe infections (grade 3 to 4), acute cardiac toxicity, or deaths from toxicity have been observed. Only five patients developed delayed cardiac dysfunctions, and three patients developed acute myeloblastic leukemia. Conclusion: After a long-term follow-up in an adjuvant setting, the benefit of six cycles of FEC 50 compared with three cycles, whatever the dose, is highly significant in terms of DFS. As regards OS, the group receiving six cycles of FEC 50 has significantly better results than the group receiving three cycles of FEC 50.
Weekly Carboplatin and Paclitaxel Followed by Concomitant Paclitaxel, Fluorouracil, and Hydroxyurea Chemoradiotherapy: Curative and Organ-Preserving Therapy for Advanced Head and Neck Cancer
Authors: Vokes Everett E. , Stenson Kerstin , Rosen Fred R. , Kies Merrill S. , Rademaker Alfred W. , Witt Mary Ellyn , Brockstein Bruce E. , List Marcy A. , Fung Bing Bing , Portugal Louis , Mittal Bharat B. , Pelzer Harold , Weichselbaum Ralph R. , Haraf Daniel J. 
Published: January 2003

Purpose: The paclitaxel, fluorouracil, and hydroxyurea regimen of paclitaxel, infusional fluorouracil, hydroxyurea, and twice-daily radiation therapy (TFHX) administered every other week has resulted in 3-year survival rates of 60% of stage IV patients. Locoregional and distant failure rates were 13% and 23%, respectively. To reduce distant failure rates, we added a brief course of induction chemotherapy to TFHX. Patients and Methods: Sixty-nine patients received six weekly doses of carboplatin (AUC2) and paclitaxel (135 mg/m2) followed by five cycles of TFHX. Results: Ninety-six percent had stage IV disease. Response to induction chemotherapy was partial response 52% and complete response (CR) 35%. Symptomatically, there was a significant reduction in mouth and throat pain. The most common grade 3 or 4 toxicity was neutropenia (36%). Best response following completion of TFHX was CR in 83%. Toxicities of TFHX consisted of grade 3 or 4 mucositis (74% and 2%) and dermatitis (47% and 14%). At a median follow-up of 28 months, locoregional or systemic disease progression were each noted in five patients. The overall 3-year progression-free survival was 80% (95% confidence interval [CI], 71% to 90%), and the 2- and 3-year overall survival rates were 77% (95% CI, 66% to 87%) and 70% (95% CI, 59% to 82%), respectively. At 12 months, five patients were completely feeding-tube dependent. Conclusion: Administration of carboplatin and paclitaxel before TFHX chemoradiotherapy results in high response activity and may decrease distant failure rates. Overall survival, progression, and organ preservation/functional outcome data support definitive evaluation of this approach.
Smoking Among Participants in the Childhood Cancer Survivors Cohort: The Partnership for Health Study
Authors: Emmons Karen M. , Butterfield Rita M. , Puleo Elaine , Park Elyse R. , Mertens Ann , Gritz Ellen R. , Lahti Maureen , Li Fredrick P. 
Published: January 2003

Purpose: This article describes baseline data collection and the intervention design of Partnership for Health, a smoking cessation intervention for smokers in the Childhood Cancer Survivors Study. The purpose of this article is to evaluate demographic, psychosocial, and cancer-related factors that are associated with smoking behavior and mediators of smoking cessation. Patients and Methods: This study includes 796 smokers from the Childhood Cancer Survivors Study database who were diagnosed with cancer before the age of 21, had survived at least 5 years, and were at least 18 years of age at the time of the baseline survey. Correlates of smoking behaviors included smoking rate, number of recent quit attempts, and nicotine dependence; two key mediators of smoking cessation, readiness to quit smoking and self-efficacy, were also assessed. Results: Participants smoked, on average, 14 cigarettes/day; 53.2% were nicotine dependent, and 58% had made at least one quit attempt in the past year. Smoking behaviors were primarily associated with demographic variables; mediators of cessation were primarily associated with age at cancer diagnosis and perceived vulnerability to smoking-related illnesses. Severity of psychologic symptoms was associated with increased smoking rate, high nicotine dependence, and low self-efficacy. Support for quitting was related to smoking rate, number of quit attempts, readiness to quit smoking, and self-efficacy. Conclusion: These findings indicate that many cancer survivors who smoke are receptive to smoking cessation interventions. Factors related to mediators of smoking cessation might be particularly good targets for intervention.