Delivery of antisense oligonucleotides to neuroblastoma cells

pH-Sensitive liposomes composed of dioleoylphosphatidylethanolamine and cho lesterol hemisuccinate (3:2 mol/mol) were applied in delivery of antisense oligodeoxynucleotides (asODN) into NG 108-15 neuroblastoma and glioma cells . Fluorescently labelled asODN were entrapped in liposomes by a modified fr eeze-thawing method (20% encapsulation efficiency). The uptake of asODN (fr ee or entrapped in liposomes) by NG 108-15 cells was monitored by fluoresce nce-activated cell sorting and confocal microscopy. Delivery of asODN was s ignificantly improved when antisense were entrapped in liposomes as compare d to free (nonliposomal) asODN. The uptake was dose-dependent and optimum w as achieved after 2 h incubation. NeuroReport 11:3117-3121 (C) 2000 Lippinc ott Williams & Wilkins.