Selection and use of ligands for receptor-mediated gene delivery to myogenic cells

Abstract

Identification of myogenic cell targeting ligands is a critical observed in regenerating fibers of patients with Duchenne step in the development of synthetic vectors for gene delivmuscular dystrophy and the ability to direct a large enzyme ery to skeletal muscle. Here we describe the screening of conjugate to the cytoplasm of myotubes. Finally, we show six potential targeting ligands (insulin, insulin-like growth that incorporation of transferrin into an artificial virus confactor I, iron transferrin, gallium transferrin, alpha-bungarosisting of poly-L-lysine-condensed DNA coated with a lipid toxin and carnitine) for their ability to bind dystrophinshell (LPDII formulation) results in ligand-directed delivery deficient myotubes in vitro. Those ligands showing high of DNA to myogenic cells. This is the first report of gene levels of binding to myotubes were then tested on fully diftransfer to myogenic cells using a ligand-directed synthetic ferentiated, isolated, viable myofibers. Of the ligands vector. These results suggest that rational design of ligandtested, transferrin showed the most promise based on high directed, fully synthetic, gene delivery vehicles is a viable levels of binding to myogenic cells, high levels of receptor approach to skeletal muscle vector development.

Transfection of cultured myoblasts in high serum concentration with DODAC:DOPE liposomes

“…This is the first study reporting a liposome formulation that is completely unaffected by the presence of 95% serum. With this system we have been able to achieve a transfection efficiency in primary myoblasts comparable to that obtained by Feero and colleagues 19 in a serumfree environment using muscle-targeted liposomes. We therefore believe that the DODAC system holds considerable potential as a basis for further development, especially in the direction of improving the transfer of plasmid DNA from the cytoplasm to the nucleus.…”

“…The few reports that have dealt with the use of cationic liposomes to transfect cultured muscle cells obtained significant transfection levels only in a serumfree environment. 9,13,18,19 We and others have shown that the efficiency of liposome-DNA complexes (lipoplexes) is drastically inhibited by the presence of serum 9,11,13 and that DNA precondensation with polylysine (lipopoliplexes) can partially correct this inhibition. 9 However, the experiments reported so far were carried out at most in the presence of 10% serum, a condition that is far from that present in vivo, and the transfection levels were extremely low.…”

Fetal muscle gene transfer is not enhanced by an RGD capsid modification to high-capacity adenoviral vectors

“…13 We and others have explored different strategies for muscle-specific targeting in adult mouse muscle. [14][15][16][17][18] However, vector retargeting to enhance fetal gene transfer of muscle or other tissues has not been reported previously for any viral or nonviral vectors. Incorporation of an Arg-GlyAsp (RGD) peptide motif, which binds to vitronectin integrins, in the fiber knob of Ad vectors increases transduction efficiency of cells in culture.…”

Local and distant transfection of mdx muscle fibers with dystrophin and LacZ genes delivered in vivo by synthetic microspheres

“…16 It is also postulated that phenotypic correction of DMD requires restoration of about 20% of normal dystrophin levels in affected dystrophic muscles. 15,17 This level of dystrophin gene expression in limb muscles has recently been achieved in mdx mice transduced with a new type of adenoviral vector 4 and this approach looks especially promising when supplemented with transient immunosuppression. 5 Retroviral transduction or nonviral dystrophin gene delivery resulted in much less conspicuous transgene expression.…”