Towards safe, non-viral therapeutic gene expression in humans

Nature Reviews Genetics

Volumn 6, Issue 4, 2005, Pages 299-310

  Glover, Dominic J ^a   Lipps, Hans J ^b   Jans, David A ^a,c  

^a MONASH UNIVERSITY   (Australia)

^b UNIVERSITY OF WITTEN HERDECKE   (Germany)

^c Australian Government Australian Research Council   (Australia)

Author keywords

[No Author keywords available]

Indexed keywords

DNA; LIPOSOME;

ARTIFICIAL CHROMOSOME; CHROMOSOMAL INSTABILITY; CHROMOSOME REPLICATION; DNA INTEGRATION; GENE EXPRESSION; GENE THERAPY; HUMAN; NONVIRAL GENE DELIVERY SYSTEM; PLASMID; PRIORITY JOURNAL; REVIEW; TRANSGENE; GENE TARGETING; GENE TRANSFER; GENE VECTOR; GENETIC RECOMBINATION; METHODOLOGY; VIRUS GENE;

CHROMOSOMES, ARTIFICIAL; GENE EXPRESSION; GENE TARGETING; GENE THERAPY; GENE TRANSFER TECHNIQUES; GENES, VIRAL; GENETIC VECTORS; HUMANS; LIPOSOMES; PLASMIDS; RECOMBINATION, GENETIC; TRANSGENES;

EID: 15944400651     PISSN: 14710056     EISSN: None     Source Type: Journal    
DOI: 10.1038/nrg1577     Document Type: Review

References (145)

1. Hacein-Bey-Abina, S. et al. Sustained correction of X-linked severe combined immunodeficiency by ex vivo gene therapy. N. Engl. J. Med. 346, 1185-1193 (2002).
2. + cells from patients with X-linked chronic granulomatous disease. Blood 100, 4381-4390 (2002).
3. Hollon, T. Researchers and regulators reflect on first gene therapy death. Nature Med. 6, 6 (2000).
4. Schroder, A. R. et al. HIV-1 integration in the human genome favors active genes and local hotspots. Cell 110, 521-529 (2002).
5. Woods, N. B. et al. Lentiviral vector transduction of NOD/SCID repopulating cells results in multiple vector integrations per transduced cell: risk of insertional mutagenesis. Blood 101, 1284-1289 (2003).
6. Li, Z. et al. Murine leukemia induced by retroviral gene marking. Science 296, 497 (2002).
7. Wu, X., Li, Y., Crise, B. & Burgess, S. M. Transcription start regions in the human genome are favored targets for MLV integration. Science 300, 1749-1751 (2003).
8. Hacein-Bey-Abina, S. et al. A serious adverse event after successful gene therapy for X-linked severe combined immunodeficiency. N. Engl. J. Med. 348, 255-256 (2003).
9. Hacein-Bey-Abina, S. et al. LMO2-associated clonal T cell proliferation in two patients after gene therapy for SCID-X1. Science 302, 415-419 (2003). A report of the development of leukaemia in two patients that had been successfully cured of SCIDX1.
10. McCormack, M. P., Forster, A., Drynan, L., Pannell, R. & Rabbitts, T. H. The LMO2 T-cell oncogene is activated via chromosomal translocations or retroviral insertion during gene therapy but has no mandatory role in normal T-cell development. Mol. Cell Biol. 23, 9003-9013 (2003).
11. Dave, U. P., Jenkins, N. A. & Copeland, N. G. Gene therapy insertional mutagenesis insights. Science 303, 333 (2004).
12. Thomas, C. E., Ehrhardt, A. & Kay, M. A. Progress and problems with the use of viral vectors for gene therapy. Nature Rev. Genet. 4, 346-358 (2003). A comprehensive overview of the current and future challenges of using viruses for gene delivery.
13. Johnson-Saliba, M. & Jans, D. A. Gene therapy: optimising DNA delivery to the nucleus. Curr. Drug Targets 2, 371-399 (2001).
14. Ferber, D. Gene therapy. Safer and virus-free? Science 294, 1638-1642 (2001).
15. Kircheis, R. et al. Polyethylenimine/DNA complexes shielded by transferrin target gene expression to tumors after systemic application. Gene Ther. 8, 28-40 (2001).
16. Jans, D. A., Xiao, C. Y. & Lam, M. H. Nuclear targeting signal recognition: a key control point in nuclear transport? Bioessays 22, 532-544 (2000).
17. Lyman, S. K., Guan, T., Bednenko, J., Wodrich, H. & Gerace, L. Influence of cargo size on Ran and energy requirements for nuclear protein import. J. Cell Biol. 159, 55-57 (2002).
18. Kursa, M. et al. Novel shielded transferrin-polyethylene glycol-polyethylenimine/DNA complexes for systemic tumor-targeted gene transfer. Bioconjug. Chem. 14, 222-231 (2003).
19. Chan, C. K. & Jans, D. A. Enhancement of MSH receptor-and GAL4-mediated gene transfer by switching the nuclear import pathway. Gene Ther. 8, 166-171 (2001).
20. Kakudo, T. et al. Transferrin-modified liposomes equipped with a pH-sensitive fusogenic peptide: an artificial viral-like delivery system. Biochemistry 43, 5618-5628 (2004).
21. Zanta, M. A., Belguise-Valladier, P. & Behr, J. P. Gene delivery: a single nuclear localization signal peptide is sufficient to carry DNA to the cell nucleus. Proc. Natl Acad. Sci. USA 96, 91-96 (1999).
22. Uherek, C., Fominaya, J. & Wels, W. A modular DNA carrier protein based on the structure of diphtheria toxin mediates target cell-specific gene delivery. J. Biol. Chem. 273, 8835-8841 (1998). A classic paper showing that novel proteins engineered to overcome cellular barriers to gene delivery can efficiently transfect target cells.
23. Box, M. et al. A multi-domain protein system based on the HC fragment of tetanus toxin for targeting DNA to neuronal cells. J. Drug Target. 11, 333-343 (2003).
24. Kapsa, R. et al. In vivo and in vitro correction of the mdx Dystrophin gene nonsense mutation by short-fragment homologous replacement. Hum. Gene Ther. 12, 629-642 (2001).
25. Goncz, K. K., Prokopishyn, N. L., Chow, B. L., Davis, B. R. & Gruenert, D. C. Application of SFHR to gene therapy of monogenic disorders. Gene Ther. 9, 691-694 (2002).
26. Voziyanov, Y., Pathania, S. & Jayaram, M. A general model for site-specific recombination by the integrase family recombinases. Nucleic Acids Res. 27, 930-941 (1999).
27. Kolot, M., Silberstein, N. & Yagil, E. Site-specific recombination in mammalian cells expressing the Int recombinase of bacteriophage HK022. Mol. Biol. Rep. 26, 207-213 (1999).
28. Thyagarajan, B., Guimaraes, M. J., Groth, A. C. & Calos, M. P. Mammalian genomes contain active recombinase recognition sites. Gene 244, 47-54 (2000).
29. Ortiz-Urda, S. et al. Stable nonviral genetic correction of inherited human skin disease. Nature Med. 8, 1165-1170 (2002).
30. Olivares, E. C. et al. Site-specific genomic integration produces therapeutic Factor IX levels in mice. Nature Biotechnol. 20, 1124-1128 (2002). The first in vivo demonstration of the ability of the phage φC31 integrase to integrate a corrective gene into liver cells and express therapeutic levels of coagulation factor IX in mice.
31. Dymecki, S. M. Flp recombinase promotes site-specific DNA recombination in embryonic stem cells and transgenic mice. Proc. Natl Acad. Sci. USA 93, 6191-6196 (1996).
32. Buchholz, F., Angrand, P. O. & Stewart, A. F. Improved properties of FLP recombinase evolved by cycling mutagenesis. Nature Biotechnol. 16, 657-662 (1998).
33. Christ, N., Corona, T. & Droge, P. Site-specific recombination in eukaryotic cells mediated by mutant λ integrases: implications for synaptic complex formation and the reactivity of episomal DNA segments. J. Mol. Biol. 319, 305-314 (2002).
34. Esposito, D., Thrower, J. S. & Scocca, J. J. Protein and DNA requirements of the bacteriophage HP1 recombination system: a model for intasome formation. Nucleic Acids Res. 29, 3955-3964 (2001).
35. Olivares, E. C., Hollis, R. P. & Calos, M. P. Phage R4 integrase mediates site-specific integration in human cells. Gene 278, 167-176 (2001).
36. Hollis, R. P. et al. Phage integrases for the construction and manipulation of transgenic mammals. Reprod. Biol. Endocrinol. 1, 79-89 (2003).
37. Groth, A. C., Olivares, E. C., Thyagarajan, B. & Calos, M. P. A phage integrase directs efficient site-specific integration in human cells. Proc. Natl Acad. Sci. USA 97, 5995-6000 (2000).
38. Thyagarajan, B., Olivares, E. C., Hollis, R. P., Ginsburg, D. S. & Calos, M. P. Site-specific genomic integration in mammalian cells mediated by phage φC31 integrase. Mol. Cell Biol. 21, 3926-3934 (2001).
39. Ortiz-Urda, S. et al. φC31 integrase-mediated nonviral genetic correction of junctional epidermolysis bullosa. Hum. Gene Ther. 14, 923-928 (2003).
40. Ortiz-Urda, S. et al. Injection of genetically engineered fibroblasts corrects regenerated human epidermolysis bullosa skin tissue. J. Clin. Invest. 111, 251-255 (2003).
41. Quennevillea, S. P. et al. Nucleofection of muscle-derived stem cells and myoblasts with C31 integrase: stable expression of a full-length-dystrophin fusion gene by human myoblasts. Mol. Ther. 10, 679-687 (2004).
42. Gagneten, S., Le, Y., Miller, J. & Sauer, B. Brief expression of a GFP ere fusion gene in embryonic stem cells allows rapid retrieval of site-specific genomic deletions. Nucleic Acids Res. 25, 3326-3331 (1997).
43. Peitz, M., Pfannkuche, K., Rajewsky, K. & Edenhofer, F. Ability of the hydrophobic FGF and basic TAT peptides to promote cellular uptake of recombinant Cre recombinase: a tool for efficient genetic engineering of mammalian genomes. Proc. Natl Acad. Sci. USA 99, 4489-4494 (2002).
44. Le, Y., Gagneten, S., Tombaccini, D., Bethke, B. & Sauer, B. Nuclear targeting determinants of the phage P1 ere DNA recombinase. Nucleic Acids Res. 27, 4703-4709 (1999).
45. Andreas, S., Schwenk, F., Kuter-Luks, B., Faust, N. & Kuhn, R. Enhanced efficiency through nuclear localization signal fusion on phage φC31-integrase: activity comparison with Cre and FLPe recombinase in mammalian cells. Nucleic Acids Res. 30, 2299-2306 (2002). This article describes how the addition of a nuclear localization signal improves the ability of the phage ΦC31 integrase to enter the eukaryotic nucleus and mediate recombination.
46. Stemmer, W. P. Rapid evolution of a protein in vitro by DNA shuffling. Nature 370, 389-391 (1994).
47. Sclimenti, C. R., Thyagarajan, B. & Calos, M. P. Directed evolution of a recombinase for improved genomic integration at a native human sequence. Nucleic Acids Res. 29, 5044-5051 (2001).
48. Santoro, S. W. & Schultz, P. G. Directed evolution of the site specificity of Cre recombinase. Proc. Natl Acad. Sci. USA 99, 4185-4190 (2002).
49. Buchholz, F. & Stewart, A. F. Alteration of Cre recombinase site specificity by substrate-linked protein evolution. Nature Biotechnol. 19, 1047-1052 (2001). This study describes an efficient and innovative approach for evolving a recombinase that recognizes new recombination sites.
50. Huser, D., Weger, S. & Heilbronn, R. Kinetics and frequency of adeno-associated virus site-specific integration into human chromosome 19 monitored by quantitative real-time PCR. J. Virol. 76, 7554-7559 (2002).
51. Rizzuto, G. et al. Development of animal models for adeno-associated virus site-specific integration. J. Virol. 73, 2517-2526 (1999).
52. Dutheil, N., Shi, F., Dupressoir, T. & Linden, R. M. Adeno-associated virus site-specifically integrates into a muscle-specific DNA region. Proc. Natl Acad. Sci. USA 97, 4862-4866 (2000).
53. Surosky, R. T. et al. Adeno-asscciated virus Rep proteins target DNA sequences to a unique locus in the human genome. J. Virol. 71, 7951-7959 (1997).
54. Lamartina, S., Roscilli, G., Rinaudo, D., Delmastro, P. & Toniattt, C. Lipofection of purified adeno-associated virus Rep68 protein: toward a chromosome-targeting nonviral particle. J. Virol. 72, 7653-7658 (1998).
55. Young, S. M., McCarty, D. M., Degtyareva, N. & Samulski, R. J. Roles of adeno-associated virus Rep protein and human chromosome 19 in site-specific recombination. J. Virol. 74, 3953-3966 (2000).
56. Manno, C. S. et al. AAV-mediated factor IX gene transfer to skeletal muscle in patients with severe hemophilia B. Blood 101, 2963-2972 (2003).
57. Moskalenko, M. et al. Epitope mapping of human anti-adeno-associated virus type 2 neutralizing antibodies: implications for gene therapy and virus structure. J. Virol. 74, 1761-1766 (2000).
58. Dong, J. Y., Fan, P. D. & Frizzell, R. A. Quantitative analysis of the packaging capacity of recombinant adeno-associated virus. Hum. Gene Ther. 7, 2101-2112 (1996).
59. Duan, D. et al. Circular intermediates of recombinant adeno-associated virus have defined structural characteristics responsible for long-term episomal persistence in muscle tissue. J. Virol. 72, 8568-8577 (1998).
60. Miller, D. G., Petek, L. M. & Russell, D. W. Adeno-associated virus vectors integrate at chromosome breakage sites. Nature Genet. 36, 767-773 (2004).
61. Nakai, H. et al. AAV serotype 2 vectors preferentially integrate into active genes in mice. Nature Genet. 34, 297-302 (2003). This study shows that rAAV vectors (which lack rep) integrate in a non-random fashion at high frequency into active genes of experimental animals.
62. Donsante, A. et al. Observed incidence of tumorigenesis in long-term rodent studies of rAAV vectors. Gene Ther. 8, 1343-1346 (2001).
63. Balague, C., Kalla, M. & Zhang, W. W. Adeno-associated virus Rep78 protein and terminal repeats enhance integration of DNA sequences into the cellular genome. J. Virol. 71, 3299-3306 (1997).
64. Pieroni, L. et al. Targeted integration of adeno-associated virus-derived plasmids in transfected human cells. Virology 249, 249-259 (1998).
65. Steigerwald, R. et al. Requirements for adeno-associated virus-derived non-viral vectors to achieve stable and site-specific integration of plasmid DNA in liver carcinoma cells. Digestion 68, 13-23 (2003).
66. Philpott, N. J. et al. Efficient integration of recombinant adeno-associated virus DNA vectors requires a p5-rep sequence in cis. J. Virol. 76, 5411-5421 (2002). This report shows that a 138 bp cis element within the p5 promoter is able to mediate efficient site-specific integration of plasmid in the absence of the AAV inverted terminal-repeat elements.
67. Philpott, N. J., Gomos, J. & Falck-Pedersen, E. Transgene expression after Rep-mediated site-specific integration into chromosome 19. Hum. Gene Ther. 15, 47-61 (2004).
68. Kogure, K. et al. Targeted integration of foreign DNA into a defined locus on chromosome 19 in K562 cells using AAV-derived components. Int. J. Hematol. 73, 469-475 (2001).
69. Urabe, M. et al. Positive and negative effects of adeno-associated virus Rep on AAVS1-targeted integration. J. Gen. Virol. 84, 2127-2132 (2003).
70. Tsunoda, H., Hayakawa, T., Sakuragawa, N. & Koyama, H. Site-specific integration of adeno-associated virus-based plasmid vectors in lipofected HeLa cells. Virology 268, 391-401 (2000).
71. Philpott, N. J., Gomos, J., Berns, K. I. & Falck-Pedersen, E. A p5 integration efficiency element mediates Rep-dependent integration into AAVS1 at chromosome 19. Proc. Natl Acad. Sci. USA 99, 12381-12385 (2002).
72. Satoh, W., Hirai, Y., Tamayose, K. & Shimada, T. Site-specific integration of an adeno-associated virus vector plasmid mediated by regulated expression of Rep based on Cre-loxP recombination. J. Virol. 74, 10631-10638 (2000).
73. Rinaudo, D., Lamartina, S., Roscilli, G., Ciliberto, G. & Toniatti, C. Conditional site-specific integration into human chromosome 19 by using a ligand-dependent chimeric adeno-associated virus/Rep protein. J. Virol. 74, 281-294 (2000).
74. Bushman, F. D. Tethering human immunodeficiency virus 1 integrase to a DNA site directs integration to nearby sequences. Proc. Natl Acad. Sci. USA 91, 9233-9237 (1994).
75. Holmes-Son, M. L. & Chow, S. A. Correct integration mediated by integrase-LexA fusion proteins incorporated into HV-1. Mol. Ther. 5, 360-370 (2002).
76. Dildine, S. L., Respess, J., Jolly, D. & Sandmeyer, S. B. A chimeric Ty3/Moloney murine leukemia virus integrase protein is active in vivo. J. Virol. 72, 4297-4307 (1998).
77. Tan, W., Zhu, K., Segal, D. J., Barbas, C. F. & Chow, S. A. Fusion proteins consisting of human immunodeficiency virus type 1 integrase and the designed polydactyl zinc finger protein E2C direct integration of viral DNA into specific sites. J. Virol. 78, 1301-1313 (2004).
78. Ali, S. H., Kasper, J. S., Arai, T. & DeCaprio, J. A. Cul7/p185/p193 binding to simian virus 40 large T antigen has a role in cellular transformation. J. Virol. 78, 2749-2757 (2004).
79. Li, D. et al. Structure of the replicative helicase of the oncoprotein SV40 large tumour antigen. Nature 423, 512-518 (2003).
80. Humme, S. et al. The EBV nuclear antigen 1 (EBNA1) enhances B cell immortalization several thousandfold. Proc. Natl Acad. Sci. USA 100, 10989-10994 (2003).
81. Wu, H., Ceccarelli, D. F. & Frappier, L. The DNA segregation mechanism of Epstein-Barr virus nuclear antigen 1. EMBO Rep. 1, 140-144 (2000).
82. White, R. E., Wade-Martins, R. & James, M. R. Sequences adjacent to oriP improve the persistence of Epstein-Barr virus-based episomes in B cells. J. Virol. 75, 11249-11252 (2001).
83. Cooper, M. J. et al. Safety-modified episomal vectors for human gene therapy. Proc. Natl Acad. Sci. USA 94, 6450-6455 (1997).
84. Sclimenti, C. R. et al. Epstein-Barr virus vectors provide prolonged robust factor IX expression in mice. Biotechnol. Prog. 19, 144-151 (2003).
85. Wade-Martins, R., White, R. E., Kimura, H., Cook, P. R. & James, M. R. Stable correction of a genetic deficiency in human cells by an episome carrying a 115 kb genomic transgene. Nature Biotechnol. 18, 1311-1314 (2000).
86. Piechaczek, C., Fetzer, C., Baiker, A., Bode, J. & Lipps, H. J. A vector based on the SV40 origin of replication and chromosomal S/MARs replicates episomally in CHO cells. Nucleic Acids Res. 27, 426-428 (1999).
87. Schaarschmidt, D., Baltin, J., Stehle, I. M., Lipps, H. J. & Knippers, R. An episomal mammalian replicon: sequence-independent binding of the origin recognition complex. EMBO J. 23, 191-201 (2004).
88. Jenke, B. H. et al. An episomally replicating vector binds to the nuclear matrix protein SAF-A in vivo. EMBO Rep. 3, 349-354 (2002).
89. Mearini, G., Nielsen, P. E. & Fackelmayer, F. O. Localization and dynamics of small circular DNA in live mammalian nuclei. Nucleic Acids Res. 32, 2642-2651 (2004).
90. Heng, H. H. et al. Chromatin loops are selectively anchored using scaffold/matrix-attachment regions. J. Cell Sci. 117, 999-1008 (2004).
91. Goetze, S., Gluch, A., Benham, C. & Bode, J. Computational and in vitro analysis of destabilized DNA regions in the interferon gene cluster: potential of predicting functional gene domains. Biochemistry 42, 154-166 (2003).
92. Jenuwein, T. et al. Extension of Chromatin accessibility by nuclear matrix attachment regions. Nature 385, 269-272 (1997).
93. Baiker, A. et al. Mitotic stability of an episomal vector containing a human scaffold/matrix-attached region is provided by association with nuclear matrix. Nature Cell Biol. 2, 182-184 (2000). This paper demonstrates that the specific interaction between an S/MAR-containing plasmid and the nuclear matrix can confer episomal replication and retention through cell division.
94. Kipp, M. et al. SAF-Box, a conserved protein domain that specifically recognizes scaffold attachment region DNA. Mol. Cell Biol. 20, 7480-7489 (2000).
95. Stehle, I. M., Scinteie, M. F., Baiker, A., Jenke, A. C. & Lipps, H. J. Exploiting a minimal system to study the epigenetic control of DNA replication: the interplay between transcription and replication. Chromosome Res. 11, 413-421 (2003). This report shows that active transcription of the S/MAR is required for episomal replication.
96. Jenke, A. C. et al. Nuclear scaffold/matrix attached region modules linked to a transcription unit are sufficient for replication and maintenance of a mammalian episome. Proc. Natl Acad. Sci. USA 101, 11322-11327 (2004).
97. Ohba, R., Matsumoto, K. & Ishimi, Y. Induction of DNA replication by transcription in the region upstream of the human c-myc gene in a model replication system. Mol. Cell Biol. 16, 5754-5763 (1996).
98. Keller, C., Ladenburger, E. M., Kremer, M. & Knippers, R. The origin recognition complex marks a replication origin in the human TOP1 gene promoter. J Biol. Chem. 277, 31430-31440 (2002).
99. Murray, A. W. & Szostak, J. W. Construction of artificial chromosomes in yeast. Nature 305, 189-193 (1983).
100. Alazami, A. M., Mejia, J. E. & Monaco, Z. L. Human artificial chromosomes containing chromosome 17 alphoid DNA maintain an active centromere in murine cells but are not stable. Genomes 83, 844-851 (2004).
101. Harrington, J. J., Van Bokkelen, G., Mays, R. W., Gustashaw, K. & Willard, H. F. Formation of de de novo centromeres and construction of first-generation human artificial microchromosomes. Nature Genet. 15, 345-355 (1997).
102. Henning, K. A. et al. Human artificial chromosomes generated by modification of a yeast artificial chromosome containing both human alpha satellite and single-copy DNA sequences. Proc. Natl Acad. Sci. USA 96, 592-597 (1999).
103. Ebersole, T. A. et al. Mammalian artificial chromosome formation from circular alphoid input DNA does not require telomere repeats. Hum. Mol. Genet. 9, 1623-1631 (2000).
104. Farr, C. J. et al. Generation of a human X-derived minichromosome using telomere-associated chromosome fragmentation. EMBO J. 14, 5444-5454 (1995).
105. Heller, R., Brown, K. E., Burgtorf, C. & Brown, W. R. Mini-chromosomes derived from the human Y chromosome by telomere directed chromosome breakage. Proc. Natl Acad. Sci. USA 93, 7125-7130 (1996).
106. du Sart, D. et al. A functional neo-centromere formed through activation of a latent human centromere and consisting of non-alpha-satellite DNA. Nature Genet 16, 144-153 (1997).
107. Saffery, R. et al. Construction of neocentromere-based human minichromosomes by telomere-associated chromosomal truncation. Proc. Natl Acad. Sci. USA 98, 5705-5710 (2001). This paper describes the use of telomere-directed fragmentation of a neocentomere-containing chromosome to produce a minichromsome that is mitotically stable and able to interact with several centromere-associated proteins.
108. Wong, L. H., Saffery, R. & Choo, K. H. Construction of neocentromere-based human minichromosomes for gene delivery and centromere studies. Gene Ther. 9, 724-726 (2002).
109. Wong, L. H. et al. Analysis of mitotic and expression properties of human neocentromere-based transchromosomes in mice. J. Biol. Chem. 280, 3954-3962 (2005).
110. Grimes, B. R. et al. Stable gene expression from a mammalian artificial chromosome. EMBO Rep. 2, 910-914 (2001).
111. Mejia, J. E. Willmott, A., Levy, E., Earnshaw, W. C. & Larin, Z. Functional complementation of a genetic deficiency with human artificial chromosomes. Am. J. Hum. Genet. 69, 315-326 (2001).
112. Auriche, C. et al. Functional human CFTR produced by a stable minichromosome. EMBO Rep. 3, 862-868 (2002).
113. Shen, M. H. et al. A structurally defined mini-chromosome vector for the mouse germ line. Curr. Biol. 10, 31-34 (2000).
114. Telenius, H. et al. Stability of a functional murine satellite DNA-based artificial chromosome across mammalian species. Chromosome Res. 7, 3-7 (1999).
115. Lamb, B. T. et al. Introduction and expression of the 400 kilobase amyloid precursor protein gene in transgenic mice. Nature Genet. 5, 22-30 (1993).
116. Lee, J. T. & Jaenisch, R. A method for high efficiency YAC lipofection into murine embryonic stem cells. Nucleic Acids Res. 24, 5054-5055 (1996).
117. Magin-Lachmann, C. et al. In vitro and in vivo delivery of intact BAC DNA - comparison of different methods. J. Gene Med. 6, 195-209 (2004).
118. Marschall, P., Malik, N. & Larin, Z. Transfer of YACs up to 2.3 Mb intact into human cells with polyethylenimine. Gene Ther. 6, 1634-1637 (1999).
119. White, R. E. et al. Functional delivery of large genomic DNA to human cells with a peptide-lipid vector. J. Gene Med. 5, 883-892 (2003).
120. Oberle, V., de Jong, G., Drayer, J. I. & Hoekstra, D. Efficient transfer of chromosome-based DNA constructs into mammalian cells. Biochim. Biophys. Acta. 1676, 223-230 (2004).
121. Chan, C. K. & Jans, D. A. Using nuclear targeting signals to enhance non-viral gene transfer. Immunol. Cell Biol. 80, 119-130 (2002).
122. Jones, P. A. & Baylin, S. B. The fundamental role of epigenetic events in cancer. Nature Rev. Genet. 3, 415-428 (2002).
123. Grassi, G. et al. Inhibitors of DNA methylation and histone deacetylation activate cytomegalovirus promoter-controlled reporter gene expression in human glioblastoma cell line U87. Carcinogenesis 24, 1625-1635 (2003).
124. Hong, K., Sherley, J. & Lauffenburger, D. A. Methylation of episomal plasmids as a barrier to transient gene expression via a synthetic delivery vector. Biomol. Eng. 18, 185-192 (2001).
125. Hsieh, C. L. In vivo activity of murine de novo methyltransferases, Dnmt3a and Dnmt3b. Mol. Cell Biol. 19, 8211-8218 (1999).
126. Scharfmann, R., Axelrod, J. H. & Verma, I. M. Long-term in vivo expression of retrovirus-mediated gene transfer in mouse fibroblast implants. Proc. Natl Acad. Sci. USA 88, 4626-4630 (1991).
127. Li, X., Eastman, E. M., Schwartz, R. J. & Draghia-Akli, R. Synthetic muscle promoters: activities exceeding naturally occurring regulatory sequences. Nature Biotechnol. 17, 241-245 (1999).
128. Martinelli, R. & De Simone, V. Short and highly efficient synthetic promoters for melanoma-specific gene expression. FEBS Lett. 579, 153-156 (2005).
129. Villemure, J. F., Savard, N. & Belmaaza, A. Promoter suppression in cultured mammalian cells can be blocked by the chicken β-globin chromatin insulator 5′HS4 and matrix/scaffold attachment regions. J. Mol. Biol. 312, 963-974 (2001).
130. Ramezani, A., Hawley, T. S. & Hawley, R. G. Performance- and safety-enhanced lentiviral vectors containing the human interferon-β scaffold attachment region and the chicken β-globin insulator. Blood 101, 4717-4724 (2003).
131. Jenke, A. C., Scinteie, M. F., Stehle, I. M. & Lipps, H. J. Expression of a transgene encoded on a non-viral episomal vector is not subject to epigenetic silencing by cytosine methylation. Mol. Biol. Rep. 31, 85-90 (2004).
132. Chen, Z. Y., He, C. Y., Meuse, L. & Kay, M. A. Silencing of episomal transgene expression by plasmid bacterial DNA elements in vivo. Gene Ther. 11, 856-864 (2004).
133. Bigger, B. W. et al. An araC-controlled bacterial cre expression system to produce DNA minicircle vectors for nuclear and mitochondrial gene therapy. J. Biol. Chem. 276, 23018-23027 (2001).
134. Chen, Z. Y., He, C. Y., Ehrhardt, A. & Kay, M. A. Minicircle DNA vectors devoid of bacterial DNA result in persistent and high-level transgene expression in vivo. Mol. Ther. 8, 495-500 (2003).
135. Haseloff, J., Siemering, K. R., Prasher, D. C. & Hodge, S. Removal of a cryptic intron and sub-cellular localization of green fluorescent protein are required to mark transgenic Arabidopsis plants brightly. Proc. Natl Acad. Sci. USA 94, 2122-2127 (1997).
136. Sarukhan, A. et al. Successful interference with cellular immune responses to immunogenic proteins encoded by recombinant viral vectors. J. Virol. 75, 269-277 (2001).
137. + regulatory T cells inhibit immune-mediated transgene rejection. Blood 102, 4326-4328 (2003).
138. + T-cell anergy and deletion by in vivo viral gene transfer. Blood 104, 969-977 (2004).
139. Honigman, A. et al. Imaging transgene expression in live animals. Mol. Ther. 4, 239-249 (2001).
140. Zhang, G., Budker, V., Williams, P., Subbotin, V. & Wolf, J. A. Efficient expression of naked DNA delivered intraarterially to limb muscles of nonhuman primates. Hum. Gene. Ther. 12, 427-138 (2001).
141. Andre, F. & Mir, L. M. DNA electrotransfer: its principles and an updated review of its therapeutic applications. Gene Ther. 11 (Suppl. 1), 33-42 (2004).
142. Matsui, H., Johnson, L. G., Randell, S. H. & Boucher, R. C. Loss of binding and entry of liposome-DNA complexes decreases transfection efficiency in differentiated airway epithelial cells. J. Biol. Chem. 272, 1117-1126 (1997).
143. Filion, M. C. & Phillips, N. C. Toxicity and immunomodulatory activity of liposomal vectors formulated with cationic lipids toward immune effector cells. Biochim. Biophys. Acta 1329, 345-356 (1997).
144. Mislick, K. A. & Baldeschwieler, J. D. Evidence for the role of proteoglycans in cation-mediated gene transfer. Proc. Natl Acad. Sci. USA 93, 12349-12354 (1996).
145. Sonawane, N. D., Szoka, F. C. & Verkman, A. S. Chloride accumulation and swelling in endosomes enhances DNA transfer by polyamine-DNA polyplexes. J. Biol. Chem. 278, 44826-44831 (2003).