Auto-oxidation-induced fusion of lipid vesicles.

Spontaneous size changes of small unilamellar vesicles with initial mean diameters of 25 nm measured by quasi-elastic light scattering (QELS) and electron microscopy are reported. After the size conversion the vesicles have mean diameters of about 70 nm and are of the unilamellar and multilamellar type. The fact that auto-oxidation initiates this process is established by the comparison of the results for vesicles which differ only in the degree of auto-oxidation. The role of phosphatidylcholine hydroperoxides as fusogens is discussed.