UC Irvine

BACKGROUND: Lipid-mediated delivery of DNA is hindered by extracellular and intracellular barriers that significantly reduce the transfection efficiency of synthetic nonviral vectors. RESULTS: In this study we investigated the role of the actin and microtubule networks on the uptake and cytoplasmic transport of multicomponent cationic liposome-DNA complexes in CHO-K1 live cells by means of confocal laser scanning microscopy and 3D single particle tracking. Treatment with actin (latrunculin B)- and microtubule-disrupting (nocodazole) reagents indicated that intracellular trafficking of complexes predominantly involves microtubule-dependent active transport. We found that the actin network has a major effect on the initial uptake of complexes, while the microtubule network is mainly responsible for the subsequent active transportation to the lysosomes. CONCLUSION: Collectively, a strategy to improve the efficiency of lipid gene vectors can be formulated. We could find a lipid formulation that allows the nanoparticles to avoid the microtubule pathway to lysosomes.