Figure 2.

Cell Entry Routes of Receptor-Targeted LVs

Left: targeted (or untargeted) LVs pseudotyped with the glycoproteins of SINV or VSV exhibit a pH-dependent entry mechanism. Following receptor attachment, LV particles are taken up by the target cell via endocytosis. Endosomal acidification and the resulting pH drop lead to conformational changes in the glycoproteins and subsequent fusion with the endosomal membrane, enabling the capsid core containing the viral RNA to enter the cytoplasm and translocate to the nucleus. Right: in contrast, paramyxoviral receptor-targeted LVs use a pH-independent entry mechanism and enter the cell directly at the plasma membrane. By receptor binding, conformational changes result in activation of the fusion protein F, which mediates active fusion with the host cell membrane and release of the capsid core into the cytoplasm, from where it translocates to the nucleus.