Magnetic Manipulation of a Retroviral Vector Using Magnetite Cationic Liposomes

In the present study, we used magnetite nanoparticles and magnetic force to concentrate the retroviral vectors in order to enhance the transduction efficiency and to enable their magnetic manipulation. Magnetite nanoparticles modified with cationic liposomes were added to a solution containing a retroviral vector. The magnetic particles which captured the viral vectors were collected by a magnetic force, and seeded into target cells. The viral titer increased up to 55-fold and 3 times 10⁸ IU/mL. Additionally, the magnetically labeled retroviral vectors can be directed to the desired regions for infection by applying magnetic fields, and micro-patterns of gene-transduced cell regions could be created on a cellular monolayer using micro-patterned magnetic concentrators. These results suggest that this new technique provides a promising approach to capture and concentrate viral vectors, thus achieving high transduction efficiency and the ability to deliver genes to a specifically injured site by applying a magnetic field.