Figure 3. Fusion characteristics of DNA–virosomes.

Fusion with erythrocyte ghosts of empty virosomes prepared without cationic lipid (a) and DOTAP virosomes (b) or DODAC virosomes (c) with encapsulated pDNA was induced by acidification of the buffer to pH 5.5. Alternatively, fusion of DOTAP virosomes with encapsulated pDNA was measured at pH 7.4 (d), or at pH 5.5, after inactivation of HA by pre-exposure of the virosomes to low pH (e). Results of a representative experiment are shown.