01. Gene therapy Boulikas.pdf - Gene therapy & Molecular Biology

Gene Therapy and Molecular Biology Vol 1, page 23
Figure 7. Analysis of green fluorescence protein (GFP) expression in the lung using confocal microscopy. 25 µg pCMV-GFP
plasmid DNA complexed with DOTMA liposomes were injected to mice and GFP expression in the lung was examined 14 h postinjection
. (A): transmitted light image and (B): fluorescence image (green) were observed at low magnification (Bar 100 µm). C and D
are the images obtained at higher magnification showing the localization of GFP in endothelial cells (Bar 25 µm). E and F are the
images from control animals injected with pCMV-Luc plasmid rather than GFP plasmid. From Song YK, Liu F, Chu S, Liu D (1997)
Characterization of cationic liposome-mediated gene transfer in vivo by intravenous administration. Hum Gene Ther 8, 1585-1594 with
the kind permission of the authors (Dexi Liu, University of Pittsburgh) and Mary Ann Liebert, Inc.
D. Cationic lipids in oligonucleotide
transfer
Encapsulation of oligonucleotides into liposomes
increased their therapeutic index, prevented degradation in
cultured cells and in human serum and reduced toxicity to
cells (Thierry and Dritschilo, 1992; Capaccioli et al, 1993;
Morishita et al, 1993; Williams et al, 1996; Lewis et al,
1996); conjugation to a fusogenic peptide enhanced the
biological activity of antisense oligonucleotides (Bongartz
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et al, 1994). However, most studies have been performed
in cell culture, and very few in animals in vivo; there is
still an important number of improvements needed before
these approaches can move to the clinic.
Zelphati and Szoka (1997) have found that complexes
of fluorescently labeled oligonucleotides with DOTAP
liposomes entered the cell using an endocytic pathway
mainly involving uncoated vesicles; oligonucleotides
redistributed from punctate cytoplasmic regions into the
nucleus; this process was independent of acidification of