The Study Of SIP30Antisense Oligonucleotide Loaded Cationic Liposomes

Objectives:In order to screen out a security cationic liposomes(CLs) with goodtransfection ability, we prepared five CLs and went on a series of experiments toinvestigatetheir pharmaceutical properties, cytotoxicity, and the ability to deliver SIP30antisense oligonucleotide into cells.Method: We used CTAB, PEI(1800Da and25KDa) and EAADs(two kinds) aspositive charged meterials, prepared five CLs by thin-film dispersion method and ethanolinjection method. The characteristics of each CLs on size, zeta potential, encapsulationefficiency, cytotoxicity was investigated. DNase stability was wen on with agarose gelelectrophoresis method. Cellular uptake of FAM-SIP30loaded CLs was analyzed by FlowCytometry, Fluorescence Microscopy and Laser Confocal Scanning Microscopy(LCSM).Result:Five cationic liposomes were prepared: CCLs, PCLs(1800), PCLs(25K),ECLs-2and ECLs-3。The particle size of them measured were88.4±1.00,150.20±7.09,171.33±19.65,165.8±10.5,118.0±1.9nm separately; and the zeta potential were30.4±4.81,12.38±0.87,11.93±3.14,4.14±0.67,2.79±0.66mV separately. The N/P ratio when CLsalmost totally adsorbed SIP30was4.2,3,3,10,20separately, and each CLs showed acertain extend protection on SIP30in DNase assay. The result of Flow Cytometry andFluorescence Microscopy showed that PCLs(25K) and ECLs-3had better ability ofdelivering SIP30into cells than any other, with positive cell ratio of95.33%and86.58%,mean fluorescence intensity of4.56and18.57separately; and the uptake of PCLs(25K)and ECLs-3was endocytosis way mediated by clathrin with energy consuming. LCSMresult indicated that FAM-SIP30/PCLs(25K)uptaked by PC12cells was mostly positionedclosely around nucleus, while FAM-SIP30/ECLs-3was positioned a little far from nucleus.Conclusion：Among these cationic liposomes we prepared, PCLs(25K) and ECLs-3showed a better ability to deliver SIP30into cells. PCLs(25K) was more efficient inadsorbing SIP30, but with a little cytotoxicity; ECLs-3was less efficient in adsorbing SIP30but with good cell security. ECLs-3had higher SIP30transport efficiency, butPCLs(25k) was more advantageous to SIP30into the nucleus.