Synthesis and function of sialic acid-conjugated cholesterols as ganglioside analogs: their reconstitution to liposomes and interaction with rat lymphocytes

Abstract

Sialic acid-conjugated cholesterols (SC) with different spacer lengths were synthesized as ganglioside analogs. The interaction of SC (12mol%)-containing liposomes with rat lymphocyte cells was investigated by monitoring increases in the intracellular calcium signal under a confocal fluorescence microscopy. Cells were stimulated strongly in the presence of SC-containing liposomes, while free SC not reconstituted to liposomes did not significantly stimulate the cells. The reconstitution of sialolipids to liposomes play a crucial role in the stimulation of cells. The efficiency of SC-containing liposomes was comparable to that of the naturally occurring gangliosides, GT1b-containing liposomes.