Stable and efficient gene transfer into the mutant retinal pigment epithelial cells of the Mitfvit mouse using a lentiviral vector

Purpose. The purpose of the present study was to test whether a lentiviral vector encoding the marker lacZ gene under the control of the human CMV promoter would stably infect a significant number of RPE cells in the vitiligo mouse. This mouse harbors a mutation in the microphthalmia gene in RPE cells that leads to slow progressive photoreceptor cell degeneration. Methods. Concentrated lentiviral vector HR'CMVlacZ was injected intravitreally into newborn vitiligo mice. Mice were sacrificed at various time points up to two months post-injection and eyes were processed histochemically to detect lacZ expression. Results. The lentiviral vector infected predominantly the RPE and resulted in lacZ expression in numerous RPE cells at all times analyzed. Conclusions. LacZ expression in vitiligo RPE cells appeared to be stable for a period of at least two months. These results raise the possibility of using a similar lentiviral vector for introduction of a correct copy of the microphthalmia cDNA into the RPE that may ultimately rescue photoreceptor cells in this mutant mouse.