Kundrot C E, Spangler E A, Kendall D A, MacDonald R C, MacDonald R I
Proc Natl Acad Sci U S A. 1983 Mar;80(6):1608-12. doi: 10.1073/pnas.80.6.1608.
Vesicles were constituted with glycophorin, the Sendai virus receptor of human erythrocytes, and loaded with calcein, a polar derivative of fluorescein, at self-quenching concentrations. On exposure to Sendai virus and mild hypo-osmotic stress, vesicles of the appropriate composition released a significant portion of their internal contents, as indicated by an increase in calcein fluorescence. Susceptible liposomes were not induced to leak by heat-inactivated virus or by trypsin-treated virus. The response of the vesicles to virus attachment is thus analogous to virus-induced hemolysis and presumably involves fusion of the vesicle and virus membranes. In addition to glycophorin and phosphatidylcholine, cholesterol was absolutely required for the lytic response to the virus. The need for cholesterol was not attributable to inactivation of the virus by liposomes without cholesterol. The presence of gangliosides increased the encapsulated volume of the liposomes, but gangliosides did not effectively substitute for glycophorin. Thin-layer chromatography of lipid extracted from incubated virus and liposomes containing a small amount of a fluorescent phosphatidylcholine indicated that phosphatidylcholine in the vesicle is not chemically altered by functional interaction with the virus.
囊泡由人红细胞的仙台病毒受体血型糖蛋白构成，并装载有处于自猝灭浓度的荧光素的极性衍生物钙黄绿素。在暴露于仙台病毒和轻度低渗应激时，具有适当组成的囊泡释放出其很大一部分内部内容物，钙黄绿素荧光增强表明了这一点。热灭活病毒或经胰蛋白酶处理的病毒不会诱导易感脂质体泄漏。因此，囊泡对病毒附着的反应类似于病毒诱导的溶血，大概涉及囊泡膜与病毒膜的融合。除了血型糖蛋白和磷脂酰胆碱外，胆固醇对于对病毒的裂解反应是绝对必需的。对胆固醇的需求并非归因于不含胆固醇的脂质体使病毒失活。神经节苷脂的存在增加了脂质体的包封体积，但神经节苷脂不能有效地替代血型糖蛋白。从孵育的病毒和含有少量荧光磷脂酰胆碱的脂质体中提取的脂质的薄层色谱表明，囊泡中的磷脂酰胆碱不会因与病毒的功能相互作用而发生化学改变。
