In addition, the MV H glycoprotein can be engineered allowing cell-specific targeting of LV vectors. One problem with MV glycoprotein-pseudotyped LV vectors is low titer during vector production.

The method relies on the simultaneous addition of HIV-1 LVs along with noninfectious virion-like particles carrying Vpx, a nonstructural protein encoded by the simian immunodeficiency virus (Vpx ...