helper viruses


Summary: Viruses which enable defective viruses to replicate or to form a protein coat by complementing the missing gene function of the defective (satellite) virus. Helper and satellite may be of the same or different genus.

Top Publications

  1. Parks R, Chen L, Anton M, Sankar U, Rudnicki M, Graham F. A helper-dependent adenovirus vector system: removal of helper virus by Cre-mediated excision of the viral packaging signal. Proc Natl Acad Sci U S A. 1996;93:13565-70 pubmed
    ..b>Helper viruses were constructed with packaging signals flanked by loxP sites so that in 293 cells that stably express the Cre ..
  2. Barjot C, HARTIGAN O CONNOR D, Salvatori G, Scott J, Chamberlain J. Gutted adenoviral vector growth using E1/E2b/E3-deleted helper viruses. J Gene Med. 2002;4:480-9 pubmed
    ..Methods that allow high-titer growth of gutted vectors while reducing helper contamination, and which use safer helper viruses, will facilitate the use of gutted Ad vectors in vivo.
  3. Zhang W, Geller A. [Comparison of the immune response to gene transfer into the rat brain with helper or helper virus-free HSV-1 vectors]. Hua Xi Yi Ke Da Xue Xue Bao. 2002;33:175-8 pubmed
    ..This study was conducted to compare the immune response to gene transfer with helper virus or helper virus-free vectors...
  4. Jozkowicz A, Dulak J. Helper-dependent adenoviral vectors in experimental gene therapy. Acta Biochim Pol. 2005;52:589-99 pubmed
    ..In this review we characterize the basic features of HdAd vectors and describe some of their experimental and potential clinical applications...
  5. Xiao X, Li J, Samulski R. Production of high-titer recombinant adeno-associated virus vectors in the absence of helper adenovirus. J Virol. 1998;72:2224-32 pubmed
  6. Ng P, Parks R, Graham F. Preparation of helper-dependent adenoviral vectors. Methods Mol Med. 2002;69:371-88 pubmed
  7. Davis B, Kimsey H, Kane A, Waldor M. A satellite phage-encoded antirepressor induces repressor aggregation and cholera toxin gene transfer. EMBO J. 2002;21:4240-9 pubmed
    ..The sequestration/inactivation process induced by RstC resembles those induced by mutant polyglutamine-containing proteins implicated in human neurodegenerative disorders...
  8. Sun M, Zhang G, Kong L, Holmes C, Wang X, Zhang W, et al. Correction of a rat model of Parkinson's disease by coexpression of tyrosine hydroxylase and aromatic amino acid decarboxylase from a helper virus-free herpes simplex virus type 1 vector. Hum Gene Ther. 2003;14:415-24 pubmed
    ..This improved system efficiently corrects the rat model of PD...
  9. Grandi P, Wang S, Schuback D, Krasnykh V, Spear M, Curiel D, et al. HSV-1 virions engineered for specific binding to cell surface receptors. Mol Ther. 2004;9:419-27 pubmed

More Information

Publications120 found, 100 shown here

  1. Geoffroy M, Salvetti A. Helper functions required for wild type and recombinant adeno-associated virus growth. Curr Gene Ther. 2005;5:265-71 pubmed
    ..This review will focus on the current knowledge about the helper activities provided by the most extensively studied helper viruses, Ad and HSV-1, and also illustrate the methods used to supply the helper functions rAAV assembly.
  2. Shi C, Graham F, Hitt M. A convenient plasmid system for construction of helper-dependent adenoviral vectors and its application for analysis of the breast-cancer-specific mammaglobin promoter. J Gene Med. 2006;8:442-51 pubmed
  3. Jayandharan G, Zhong L, Sack B, Rivers A, Li M, Li B, et al. Optimized adeno-associated virus (AAV)-protein phosphatase-5 helper viruses for efficient liver transduction by single-stranded AAV vectors: therapeutic expression of factor IX at reduced vector doses. Hum Gene Ther. 2010;21:271-83 pubmed publisher
    ..These included the use of scAAV helper viruses containing (1) hepatocyte-specific promoters, (2) tyrosine-mutant AAV2 capsids, and (3) additional AAV ..
  4. Lock M, Alvira M, Vandenberghe L, Samanta A, Toelen J, Debyser Z, et al. Rapid, simple, and versatile manufacturing of recombinant adeno-associated viral vectors at scale. Hum Gene Ther. 2010;21:1259-71 pubmed publisher
    ..In addition, the iodixanol gradient purification process described effectively separates infectious particles from empty capsids, a desirable property for reducing toxicity and unwanted immune responses during preclinical studies...
  5. Samulski R, Chang L, Shenk T. Helper-free stocks of recombinant adeno-associated viruses: normal integration does not require viral gene expression. J Virol. 1989;63:3822-8 pubmed
    ..Thus, AAV gene expression is not required for normal integration of an infecting DNA containing AAV termini...
  6. Lim F, Hartley D, Starr P, Lang P, Song S, Yu L, et al. Generation of high-titer defective HSV-1 vectors using an IE 2 deletion mutant and quantitative study of expression in cultured cortical cells. Biotechniques. 1996;20:460-9 pubmed
    ..Virus stocks prepared using 5dl1.2 were superior to those prepared using helper viruses that harbor a deletion in the IE 3 gene, either D30EBA or dl20, and supported more efficient gene transfer ..
  7. Qiao C, Li J, Skold A, Zhang X, Xiao X. Feasibility of generating adeno-associated virus packaging cell lines containing inducible adenovirus helper genes. J Virol. 2002;76:1904-13 pubmed
    ..Although future improvement is necessary to increase the stability and vector yield of the cells, our study has nonetheless demonstrated the feasibility of generating helper-virus-free inducible AAV producer cell lines...
  8. Toietta G, Pastore L, Cerullo V, Finegold M, Beaudet A, Lee B. Generation of helper-dependent adenoviral vectors by homologous recombination. Mol Ther. 2002;5:204-10 pubmed
    ..coli, with no significant alteration of liver enzymes and a less severe, transient thrombocytopenia in comparison with previous reports with similar doses of a FG-Ad vector...
  9. Fraefel C, Bittermann A, Bueler H, Heid I, Bächi T, Ackermann M. Spatial and temporal organization of adeno-associated virus DNA replication in live cells. J Virol. 2004;78:389-98 pubmed
    ..also associate with PML NBs, and whether modification or disruption of these by HSV-1 or Ad, both of which are helper viruses for AAV, is necessary at all...
  10. Shiau A, Liu P, Wu C. Novel strategy for generation and titration of recombinant adeno-associated virus vectors. J Virol. 2005;79:193-201 pubmed
    ..Several methods that use plasmids or helper viruses have been reported for the generation of rAAV vectors...
  11. Palmer D, Ng P. Helper-dependent adenoviral vectors for gene therapy. Hum Gene Ther. 2005;16:1-16 pubmed
    ..This review focuses on advances in helper-dependent adenoviral vector technology, selected examples of in vivo studies of particular interest, and the issue of vector-mediated acute toxicity...
  12. Li C, Samulski R. Serotype-specific replicating AAV helper constructs increase recombinant AAV type 2 vector production. Virology. 2005;335:10-21 pubmed
    ..This strategy supports development of AAV packaging systems that retain normal virus replication capability without helper virus encapsidation...
  13. Liu M, Tang J, Wang X, Yang T, Geller A. Enhanced long-term expression from helper virus-free HSV-1 vectors packaged in the presence of deletions in genes that modulate the function of VP16, U L 46 and U L 47. J Neurosci Methods. 2005;145:1-9 pubmed
    ..The implications of these results for strategies to improve long-term expression are discussed...
  14. Alazard Dany N, Nicolas A, Ploquin A, Strasser R, Greco A, Epstein A, et al. Definition of herpes simplex virus type 1 helper activities for adeno-associated virus early replication events. PLoS Pathog. 2009;5:e1000340 pubmed publisher
    ..Altogether, this work represents the first comprehensive study recapitulating the series of early events taking place during HSV-1-induced AAV replication...
  15. Weaver E, Nehete P, Buchl S, Senac J, Palmer D, Ng P, et al. Comparison of replication-competent, first generation, and helper-dependent adenoviral vaccines. PLoS ONE. 2009;4:e5059 pubmed publisher
    ..Also, HD vectors have the benefit of being packaged by all subgroup C serotype helper viruses. We found that HD serotypes 1, 2, 5, and 6 induce anti-HIV responses equivalently...
  16. Liu L, Shi C, Ghayur A, Zhang C, Su J, Hoff C, et al. Prolonged peritoneal gene expression using a helper-dependent adenovirus. Perit Dial Int. 2009;29:508-16 pubmed
    ..The causes of EPS are not well defined and are likely multifactorial. A suitable animal model would facilitate research into the pathophysiology and treatment of EPS...
  17. Samulski R, Shenk T. Adenovirus E1B 55-Mr polypeptide facilitates timely cytoplasmic accumulation of adeno-associated virus mRNAs. J Virol. 1988;62:206-10 pubmed
    ..The AAV helper function provided by the E1B 55-Mr and E4 34-Mr polypeptides appears to closely parallel their normal role in the adenovirus replication cycle...
  18. Palmer D, Ng P. Improved system for helper-dependent adenoviral vector production. Mol Ther. 2003;8:846-52 pubmed
  19. Brunetti Pierri N, Stapleton G, Palmer D, Zuo Y, Mane V, Finegold M, et al. Pseudo-hydrodynamic delivery of helper-dependent adenoviral vectors into non-human primates for liver-directed gene therapy. Mol Ther. 2007;15:732-40 pubmed
    ..Using a low, clinically relevant vector dose, this minimally invasive method results in high-efficiency hepatic transduction with minimal toxicity and stable long-term transgene expression for at least 413 days...
  20. Streiter M, Malecki M, Prokop A, Schildgen V, Lüsebrink J, Guggemos A, et al. Does human bocavirus infection depend on helper viruses? A challenging case report. Virol J. 2011;8:417 pubmed publisher
    ..The case supports the hypotheses that HBoV infection under clinical conditions may depend on helper viruses, or that HBoV replicates by a mechanism that is atypical for parvoviruses, or that HBoV infection can be ..
  21. Wu H, Guy J, Yoo D, Vlasak R, Urbach E, Brian D. Common RNA replication signals exist among group 2 coronaviruses: evidence for in vivo recombination between animal and human coronavirus molecules. Virology. 2003;315:174-83 pubmed
    ..Here, a reporter-containing BCoV DI RNA was shown to be replicated by all five BCoV-like helper viruses and by MHV-H2 (a human cell-adapted MHV strain), a representative of the MHV-like subgroup, demonstrating ..
  22. Seiler M, Cerullo V, Lee B. Immune response to helper dependent adenoviral mediated liver gene therapy: challenges and prospects. Curr Gene Ther. 2007;7:297-305 pubmed
  23. Clement N, Velu T, Brandenburger A. Construction and production of oncotropic vectors, derived from MVM(p), that share reduced sequence homology with helper plasmids. Cancer Gene Ther. 2002;9:762-70 pubmed
    ..In one of the vectors the inserted fragment of mouse genomic DNA had a synergistic effect with the modified origin of replication in increasing vector production. ..
  24. Leonard J, Ferstl P, Delgado A, Schaffer D. Enhanced preparation of adeno-associated viral vectors by using high hydrostatic pressure to selectively inactivate helper adenovirus. Biotechnol Bioeng. 2007;97:1170-9 pubmed
    ..However, helper viruses must eventually be inactivated and removed from AAV preparations to ensure safety...
  25. Wang Y, Fang L, Li J, Li Y, Cui S, Sun X, et al. Rescue of avian leukosis subgroup-J-associated acutely transforming viruses carrying different lengths of the v-fps oncogene and analysis of their tumorigenicity. Arch Virol. 2016;161:3473-3481 pubmed
  26. Sheldon C, Symons R. Is hammerhead self-cleavage involved in the replication of a virusoid in vivo?. Virology. 1993;194:463-74 pubmed
  27. Casabianca A, Orlandi C, Fraternale A, Magnani M. A new one-step RT-PCR method for virus quantitation in murine AIDS. J Virol Methods. 2003;110:81-90 pubmed
  28. Vassilopoulos G, Trobridge G, Josephson N, Russell D. Gene transfer into murine hematopoietic stem cells with helper-free foamy virus vectors. Blood. 2001;98:604-9 pubmed
    ..Transgene silencing was not observed. Thus vectors based on foamy viruses represent a promising approach for HSC gene therapy. (Blood. 2001;98:604-609)..
  29. Butti E, Bergami A, Recchia A, Brambilla E, Del Carro U, Amadio S, et al. IL4 gene delivery to the CNS recruits regulatory T cells and induces clinical recovery in mouse models of multiple sclerosis. Gene Ther. 2008;15:504-15 pubmed publisher
    ..CSF delivery of HD-Ad vectors expressing anti-inflammatory molecules might represent a valuable therapeutic option for CNS inflammatory disorders. ..
  30. Mselli Lakhal L, Guiguen F, Greenland T, Mornex J, Chebloune Y. Gene transfer system derived from the caprine arthritis-encephalitis lentivirus. J Virol Methods. 2006;136:177-84 pubmed
    ..However, these vector titers remain lower than those obtained with other lentiviral vectors carrying equivalent packaging sequences. We discuss on possible reasons of such differences and possible improvements. ..
  31. Thorne B, Quigley P, Nichols G, Moore C, Pastor E, Price D, et al. Characterizing clearance of helper adenovirus by a clinical rAAV1 manufacturing process. Biologicals. 2008;36:7-18 pubmed
    ..Overall clearance factors determined were >23 LRV for adenovirus, 11 LRV for BVDV, and >23 LRV for AMuLV. ..
  32. Grandi P, Fernandez J, Szentirmai O, Carter R, Gianni D, Sena Esteves M, et al. Targeting HSV-1 virions for specific binding to epidermal growth factor receptor-vIII-bearing tumor cells. Cancer Gene Ther. 2010;17:655-63 pubmed publisher
    ..The retargeting of HSV infection to tumor cells should enhance vector specificity, tumor cell killing and vector safety...
  33. Neve R, Lim F. Generation of high-titer defective HSV-1 vectors. Curr Protoc Neurosci. 2013;Chapter 4:Unit 4.13 pubmed publisher
    ..The Support Protocols detail methods for determining titers of helper virus by plaque assay, and of amplicon stocks by vector assay. ..
  34. Walker P, Hengge U, Udey M, Aksentijevich I, Vogel J. Viral interference during simultaneous transduction with two independent helper-free retroviral vectors. Hum Gene Ther. 1996;7:1131-8 pubmed
    ..Thus, such dual transductions will likely require in vitro selection or the use of a single retrovirus which contains both desired genes on the same genome...
  35. Cao L, During M, Xiao W. Replication competent helper functions for recombinant AAV vector generation. Gene Ther. 2002;9:1199-206 pubmed
    ..This new strategy also performs better in AAV producing cell lines than those based on non-replicating AAV rep and cap genome. ..
  36. Dudley R, Lu Y, Gilbert R, Matecki S, Nalbantoglu J, Petrof B, et al. Sustained improvement of muscle function one year after full-length dystrophin gene transfer into mdx mice by a gutted helper-dependent adenoviral vector. Hum Gene Ther. 2004;15:145-56 pubmed
    ..Our results indicate that major therapeutic benefits of HDCBDysM are maintained for a long period of the animals' lifespan and suggest that HDCBDys holds promise for treating DMD by gene therapy. ..
  37. Gonzalez Aparicio M, Mauleon I, Alzuguren P, Bunuales M, Gonzalez Aseguinolaza G, San Martin C, et al. Self-inactivating helper virus for the production of high-capacity adenoviral vectors. Gene Ther. 2011;18:1025-33 pubmed publisher
    ..1% HV contamination. The residual HVs lacked ? and were highly attenuated. We conclude that self-inactivating HVs based on virally encoded recombinases are promising tools for the production of HC-Ads. ..
  38. Belalcazar M, Chan L. Somatic gene therapy for dyslipidemias. J Lab Clin Med. 1999;134:194-214 pubmed
    ..We highlight some recent advances in adenoviral vector development that make this vector an attractive system for clinical trials. ..
  39. Tzeng W, Chen M, Derdeyn C, Frey T. Rubella virus DI RNAs and replicons: requirement for nonstructural proteins acting in cis for amplification by helper virus. Virology. 2001;289:63-73 pubmed
    ..Nevertheless, it was an unexpected finding that a small virus such as RUB could dispense with approximately 10% of its genome. ..
  40. Salucci V, Scarito A, Aurisicchio L, Lamartina S, Nicolaus G, Giampaoli S, et al. Tight control of gene expression by a helper-dependent adenovirus vector carrying the rtTA2(s)-M2 tetracycline transactivator and repressor system. Gene Ther. 2002;9:1415-21 pubmed
    ..The results allow us to draw some general conclusions about the combination of transcription regulators and their relative orientation to the transgene to achieve maximal induction, while minimizing leakiness of expression. ..
  41. Wang X, Cao B. Screening of specific internalization Fab fragment from human naive phage library by combinational bio-panning. Methods Mol Biol. 2009;525:161-74, xv pubmed publisher
  42. Brunetti Pierri N, Ng P. Helper-dependent adenoviral vectors for liver-directed gene therapy. Hum Mol Genet. 2011;20:R7-13 pubmed publisher
    ..These strategies have yielded encouraging results with the potential for clinical translation. ..
  43. Pear W, Nolan G, Scott M, Baltimore D. Production of high-titer helper-free retroviruses by transient transfection. Proc Natl Acad Sci U S A. 1993;90:8392-6 pubmed
    ..This method should facilitate and extend the use of helper-free retroviral gene transfer, as well as be useful for gene therapy. ..
  44. Ehrhardt A, Kay M. A new adenoviral helper-dependent vector results in long-term therapeutic levels of human coagulation factor IX at low doses in vivo. Blood. 2002;99:3923-30 pubmed
  45. Dormond E, Meneses Acosta A, Jacob D, Durocher Y, Gilbert R, Perrier M, et al. An efficient and scalable process for helper-dependent adenoviral vector production using polyethylenimine-adenofection. Biotechnol Bioeng. 2009;102:800-10 pubmed publisher
  46. Poirier Y, Jolicoeur P. Distinct helper virus requirements for Abelson murine leukemia virus-induced pre-B- and T-cell lymphomas. J Virol. 1989;63:2088-98 pubmed
    ..Our data also revealed distinct biological requirements for transformation of these two target cells by v-abl...
  47. Marriott A, Dimmock N. Defective interfering viruses and their potential as antiviral agents. Rev Med Virol. 2010;20:51-62 pubmed publisher
    ..In this article, we review the properties of DI virus, potential mechanisms of interference and progress in using DI virus (in particular that derived from influenza A virus) as a novel type of antiviral agent...
  48. Umeda K, Suzuki K, Yamazoe T, Shiraki N, Higuchi Y, Tokieda K, et al. Albumin gene targeting in human embryonic stem cells and induced pluripotent stem cells with helper-dependent adenoviral vector to monitor hepatic differentiation. Stem Cell Res. 2013;10:179-94 pubmed publisher
    ..These knock-in hES/iPS cell lines could provide further insights into the mechanism of hepatic differentiation and molecular signatures of the hepatic cells derived from hES/iPS cells. ..
  49. Nasz I, Adam E. Recombinant adenovirus vectors for gene therapy and clinical trials. Acta Microbiol Immunol Hung. 2001;48:323-48 pubmed
    ..However, the well-understood structure, molecular biology and host cell interactions of AdV-s offer some potential solutions to these limitations. ..
  50. Tumas D, Spangrude G, Brooks D, Williams C, Chesebro B. High-frequency cell surface expression of a foreign protein in murine hematopoietic stem cells using a new retroviral vector. Blood. 1996;87:509-17 pubmed
    ..The multilineage, high-frequency expression observed suggests that pSFF may be useful in gene therapy directed at hematopoietic stem cells and their differentiated progeny...
  51. Trobridge G, Vassilopoulos G, Josephson N, Russell D. Gene transfer with foamy virus vectors. Methods Enzymol. 2002;346:628-48 pubmed
  52. Fayzulin R, Gorchakov R, Petrakova O, Volkova E, Frolov I. Sindbis virus with a tricomponent genome. J Virol. 2005;79:637-43 pubmed
    ..The formation of infectious recombinant SIN virus was not detected in any experiments. These features make multicomponent genome SIN an attractive system for a variety of research and biotechnology applications...
  53. Lamartina S, Cimino M, Roscilli G, Dammassa E, Lazzaro D, Rota R, et al. Helper-dependent adenovirus for the gene therapy of proliferative retinopathies: stable gene transfer, regulated gene expression and therapeutic efficacy. J Gene Med. 2007;9:862-74 pubmed
    ..HD-Ad vectors enable stable gene transfer and regulated expression of angiostatic factors following intravitreous injection and thus are attractive vehicles for the gene therapy of neovascular diseases of the retina. ..
  54. Miller A. Production of retroviral vectors. Curr Protoc Hum Genet. 2001;Chapter 12:Unit 12.5 pubmed publisher
    ..Vectors that contain sequence for alkaline phosphatase can be assayed histochemically. In this unit, the basic protocol generates stable cell lines, which produce retroviral vectors that carry selectable markers. ..
  55. Parkin N, Chiu P, Coelingh K. Temperature sensitive mutants of influenza A virus generated by reverse genetics and clustered charged to alanine mutagenesis. Virus Res. 1996;46:31-44 pubmed
    ..This approach has thus yielded several vaccine candidates with ts and attenuated characteristics in animal models. Combination of these mutations with each other or with other ts mutations may lead to a high level of genetic stability. ..
  56. Gao Q, Sun M, Wang X, Zhang G, Geller A. Long-term inducible expression in striatal neurons from helper virus-free HSV-1 vectors that contain the tetracycline-inducible promoter system. Brain Res. 2006;1083:1-13 pubmed
    ..Of note, only the vector design that used the modified neurofilament promoter to express tet-off supported long-term (2 months) inducible expression in striatal neurons. ..
  57. Oh M, Joo H, Hur B, Jeong Y, Cha S. Enhancing phage display of antibody fragments using gIII-amber suppression. Gene. 2007;386:81-9 pubmed
  58. Dombrovsky A, Gollop N, Chen S, Chejanovsky N, Raccah B. In vitro association between the helper component-proteinase of zucchini yellow mosaic virus and cuticle proteins of Myzus persicae. J Gen Virol. 2007;88:1602-10 pubmed
    ..The putative CuPs from M. persicae that bind HC-Pro are potentially of interest in locating receptors for virions bound to HC-Pro in aphids' stylets. ..
  59. Ubeda C, Maiques E, Barry P, Matthews A, Tormo M, Lasa I, et al. SaPI mutations affecting replication and transfer and enabling autonomous replication in the absence of helper phage. Mol Microbiol. 2008;67:493-503 pubmed
    ..We have not yet ascertained any specific function for the second putative regulatory gene, though it is highly conserved among the SaPIs. ..
  60. Cao M, Zhu H, Bandyopadhyay S, You H, Hermonat P. HPV-16 E1, E2 and E6 each complement the Ad5 helper gene set, increasing rAAV2 and wt AAV2 production. Gene Ther. 2012;19:418-24 pubmed publisher
    ..These results raise the possibility of generating improved helper gene sets derived from both the Ad and HPV helper gene sets. ..
  61. Kopelovich L, Wang T. Histiocytic conversion of human adult skin fibroblasts by the Snyder-Theilen feline sarcoma virus. Eur Cytokine Netw. 1990;1:157-68 pubmed
  62. Ting Y, Wilson C, Farrell K, Chaudry G, Eiden M. Simian sarcoma-associated virus fails to infect Chinese hamster cells despite the presence of functional gibbon ape leukemia virus receptors. J Virol. 1998;72:9453-8 pubmed
    ..This finding indicates that the region of the SSAV envelope protein responsible for restricting SSAV infection of E36 cells lies within its amino-terminal region...
  63. Kurre P, Morris J, Horn P, Harkey M, Andrews R, Kiem H. Gene transfer into baboon repopulating cells: A comparison of Flt-3 Ligand and megakaryocyte growth and development factor versus IL-3 during ex vivo transduction. Mol Ther. 2001;3:920-7 pubmed
  64. le Mercier P, Jacob Y, Tanner K, Tordo N. A novel expression cassette of lyssavirus shows that the distantly related Mokola virus can rescue a defective rabies virus genome. J Virol. 2002;76:2024-7 pubmed
  65. Qiu W, Scholthof K. Satellite panicum mosaic virus capsid protein elicits symptoms on a nonhost plant and interferes with a suppressor of virus-induced gene silencing. Mol Plant Microbe Interact. 2004;17:263-71 pubmed
    ..Therefore, the roles of the SPMV CP now include encapsidation of the SPMV RNA, activity as a pathogenicity factor in both host and nonhost plants, and the enigmatic feature of interfering with suppression of gene silencing...
  66. Gorantla S, Santos K, Meyer V, Dewhurst S, Bowers W, Federoff H, et al. Human dendritic cells transduced with herpes simplex virus amplicons encoding human immunodeficiency virus type 1 (HIV-1) gp120 elicit adaptive immune responses from human cells engrafted into NOD/SCID mice and confer partial protection against HIV-1. J Virol. 2005;79:2124-32 pubmed
    ..This mouse model may be a useful tool to evaluate human immune responses and protection against viral infection following vaccination. ..
  67. Choi S, Seo J, Kwon S, Rao A. Helper virus-independent transcription and multimerization of a satellite RNA associated with cucumber mosaic virus. J Virol. 2012;86:4823-32 pubmed publisher
  68. Franzoso F, Seyffert M, Vogel R, Yakimovich A, de Andrade Pereira B, Meier A, et al. Cell Cycle-Dependent Expression of Adeno-Associated Virus 2 (AAV2) Rep in Coinfections with Herpes Simplex Virus 1 (HSV-1) Gives Rise to a Mosaic of Cells Replicating either AAV2 or HSV-1. J Virol. 2017;91: pubmed publisher
    ..AAV2 has been shown to efficiently inhibit the replication of helper viruses. Here we present a new facet of the interaction between AAV2 and one of its helper viruses, herpes simplex ..
  69. Muenchau D, Ruscetti S, Anderson W. Sequences present in a small region of the AKV virus envelope gene determine the efficiency with which pseudotyped spleen focus-forming virus infects erythroid target cells. Virology. 1992;186:161-6 pubmed
  70. Fuller M, Anson D. Helper plasmids for production of HIV-1-derived vectors. Hum Gene Ther. 2001;12:2081-93 pubmed
  71. Gal On A, Kaplan I, Palukaitis P. Differential effects of satellite RNA on the accumulation of cucumber mosaic virus RNAs and their encoded proteins in tobacco vs zucchini squash with two strains of CMV helper virus. Virology. 1995;208:58-66 pubmed
  72. El Andaloussi N, Endele M, Leuchs B, Bonifati S, Kleinschmidt J, Rommelaere J, et al. Novel adenovirus-based helper system to support production of recombinant parvovirus. Cancer Gene Ther. 2011;18:240-9 pubmed publisher
    ..This Ad-VP helper-based protocol could be scaled up to a bioreactor format for the generation of the large amounts of recPVs needed for future clinical applications...
  73. Roossinck M, Palukaitis P. Differential replication in zucchini squash of a cucumber mosaic virus satellite RNA maps to RNA 1 of the helper virus. Virology. 1991;181:371-3 pubmed
    ..Using pseudorecombinants constructed between Fny-CMV and Sny-CMV we have mapped to RNA 1 the ability to support the efficient replication of WL1-sat RNA in zucchini squash. ..
  74. Drittanti L, Jenny C, Poulard K, Samba A, Manceau P, Soria N, et al. Optimised helper virus-free production of high-quality adeno-associated virus vectors. J Gene Med. 2001;3:59-71 pubmed
    ..This work demonstrates the possibility of producing purified high-quality rAAV free of helper virus. The procedure described in this paper is easily adaptable for large-scale production of clinical rAAV vectors. ..
  75. Prieto J, Solera J, Tabarés E. Development of new expression vector based on Pseudorabies virus amplicons: application to human insulin expression. Virus Res. 2002;89:123-9 pubmed
  76. Li J, Hankins G, Kao C, Li H, Kammauff J, Helm G. Osteogenesis in rats induced by a novel recombinant helper-dependent bone morphogenetic protein-9 (BMP-9) adenovirus. J Gene Med. 2003;5:748-56 pubmed
    ..Additional direct and ex vivo BMP gene therapy studies are required to assess the vector's activity in more animal models. ..
  77. Sova P, Wang H, Bomsztyk K, Stamatoyannopoulos G, Lieber A. Role of chromatin structure in integration of helper-dependent adenoviral vectors containing the beta-globin locus control region. Hum Gene Ther. 2008;19:153-66 pubmed publisher
    ..We also provide data that suggest a role for active chromatin in AAV Rep78-mediated Ad.LCR integration. Our findings support a new strategy for achieving targeted integration through chromatin tethering of vector DNA. ..
  78. Lim F, Neve R. Generation of high-titer defective HSV-1 vectors. Curr Protoc Neurosci. 2001;Chapter 4:Unit 4.13 pubmed publisher
    ..Support protocols detail methods for determining titers of helper virus and wild-type virus by plaque assay, and of amplicon stocks by vector assay. ..
  79. Lang M, Treinies I, Duesberg P, Kurth R, Cichutek K. Development of transforming function during transduction of proto-ras into Harvey sarcoma virus. Proc Natl Acad Sci U S A. 1994;91:654-8 pubmed
    ..During the genesis of Harvey sarcoma virus, critical steps conferring transforming function are therefore transduction of coding proto-ras exons and enhancement of their transforming function by specific amino acid changes in p21ras...
  80. Zhou H, Pastore L, Beaudet A. Helper-dependent adenoviral vectors. Methods Enzymol. 2002;346:177-98 pubmed
  81. Russell R, Vassaux G, Martin Duque P, McClure M. Transient foamy virus vector production by adenovirus vectors. Gene Ther. 2004;11:310-6 pubmed
    ..In short, this paper describes the production of a hybrid vector capable of high in vitro transduction and stable transgene expression using adenovirus and PFV vectors...
  82. Puntel M, Curtin J, Zirger J, Muhammad A, Xiong W, Liu C, et al. Quantification of high-capacity helper-dependent adenoviral vector genomes in vitro and in vivo, using quantitative TaqMan real-time polymerase chain reaction. Hum Gene Ther. 2006;17:531-44 pubmed
    ..This approach will allow accurate assessment of the levels and biodistribution of HC-Ad and improve the safety and efficacy of clinical trials...
  83. Tallent S, Langston T, Moran R, Christie G. Transducing particles of Staphylococcus aureus pathogenicity island SaPI1 are comprised of helper phage-encoded proteins. J Bacteriol. 2007;189:7520-4 pubmed
    ..No SaPI1-encoded proteins were detected. This confirms the prediction that SaPI1 is encapsidated in a virion assembled from helper phage-encoded proteins...
  84. Poliakov A, Chang J, Spilman M, Damle P, Christie G, Mobley J, et al. Capsid size determination by Staphylococcus aureus pathogenicity island SaPI1 involves specific incorporation of SaPI1 proteins into procapsids. J Mol Biol. 2008;380:465-75 pubmed publisher
    ..Mass spectrometry on full-length phage proteins showed that the major capsid protein and the scaffolding protein are N-terminally processed in both 80alpha and SaPI1 procapsids...
  85. O Neal W, Zhou H, Morral N, Langston C, Parks R, Graham F, et al. Toxicity associated with repeated administration of first-generation adenovirus vectors does not occur with a helper-dependent vector. Mol Med. 2000;6:179-95 pubmed
  86. Collaco R, Trempe J. A method for helper virus-free production of adeno-associated virus vectors. Methods Mol Med. 2003;76:237-54 pubmed
  87. Borst E, Messerle M. Construction of a cytomegalovirus-based amplicon: a vector with a unique transfer capacity. Hum Gene Ther. 2003;14:959-70 pubmed
    ..The CMV amplicon vector has the potential to transfer therapeutic genes with a size of more than 200 kbp and thus provides a unique transfer capacity among viral vectors...
  88. Hsu Y, Chen H, Cheng J, Annamalai P, Annamali P, Lin B, et al. Crucial role of the 5' conserved structure of bamboo mosaic virus satellite RNA in downregulation of helper viral RNA replication. J Virol. 2006;80:2566-74 pubmed
    ..The conserved secondary structure within the HV region is a potent determinant of the downregulation of helper virus replication...
  89. Brunetti Pierri N, Ng P. Progress and prospects: gene therapy for genetic diseases with helper-dependent adenoviral vectors. Gene Ther. 2008;15:553-60 pubmed publisher
  90. Long N, Hardiville S, Pierce A, Fukamachi K, Futakuchi M, Alexander D, et al. Construction of a multi-functional helper-dependent adenovirus based system for cancer gene therapy. Asian Pac J Cancer Prev. 2009;10:939-60 pubmed
    ..This type of system could be very useful in cancer therapy: For example, libraries of different cassettes could be maintained, allowing rapid assembly of constructs able to provide therapy for individual tumor types...
  91. Benskey M, Manfredsson F. Lentivirus Production and Purification. Methods Mol Biol. 2016;1382:107-14 pubmed publisher
  92. Moore B, Bose H. Transformation of avian lymphoid cells by reticuloendotheliosis virus. Mutat Res. 1988;195:79-90 pubmed
    ..This review discusses the molecular aspects of transformation by REV-T in the context of other oncogene-encoded proteins...