When unilamellar vesicles were administered subcutaneously in mice, the half-time for the destruction of the vesicles varied from 12 to 600 hours, depending on their composition. The vesicles tested consisted of distearoyl phosphatidylcholine, cholesterol, and certain sugar and amino-sugar derivatives of cholesterol. Vesicle with amino-sugar derivatives showed the greatest longevity and became localized with high specificity in aggregates of polymorphonuclear leukocytes. A substantial delay between the time that the vesicles broke open and the time that labels contained in the vesicles were excreted suggests that the vesicles undergo endocytosis before destruction.
Animals Cholesterol