| With the implementation of Human Gene Project (HGP) and the further identification of genetical materials cause disease, gene therapy represents a new and promising therapeutics modality. The principal problem of gene therapy is focused on transferring genetic material into targeted cells. However, these genetic material (e.g. DNA, RNA, and antisense nucleotides) processes several inherent characteristics of hydrophilic, polyanionic and large macromoleculars, which restrict the poor permeation of cell membranes. In addition, the rapid degradation by nuclease leads to the short biological half-life. Due to these challenges, one of the most urgent tasks that scientists are devoted to is developing the gene delivery system. The term of efficient and safe gene delivery system should embrace both high efficient and targeted expression of genetic material and effective regulation of expression. At present, the vehicles for delivering gene can be divided into two major groups: viral and non-viral vectors. In general, viruses are very efficient gene-transfer vehicles; however, the significant problem of security and immunogenicity caused by viral vectors are limited to their use. Non-viral vectors are mainly referred to the nanoparticles delivery system such as cationic liposomes, polymers and micelles. Among these, cationic liposomes is one of the mostattractive non-virus vectors due to the simplified preparation, biodegradation in vivo, non-immunogenicity, and the feasibility of repeated transfection. However, the relative low transfection efficiency of cationic liposomes is still major obstacle in their application compared to the virus vectors. Recently, based on the advantage of virus and no-virus vectors, a new hybrid liposomes vector used for delivery gene--Fusogenic Liposomes (FL) is developed. FL is prepared by fusing conventional liposomes with a specified and ultra-violet inactivated Sendai virus. The typical advantage of FL delivering gene is both high efficient transfection and low toxicity due to the fusion properties of virus with cell while keeping the characteristic of non-virus vector.Telomerase is a telomere-specific reverse transcriptase. It is a ribonucleoprotein composed of RNA and proteins, in which the RNA component provides the template for the synthesis of telomeric repeats at the end of the chromosome to maintain chromosomals stability and promote cell immortality. Recent studies indicated that there exists a close relationship between telomerase activity and cancer's occurrence and development. The growth of cancer cells can be obviously inhibited and cells can be induced to apoptosis by restraining the activity of telomerase because of the anti-apototic capability of telomerase. It is an attractive potential gene therapy for targeting cancer by inhibiting the activity of telomerase, shorting the length of telomere and leading to the cancer cells using antisene therapy complementing to telomerase.In this paper, cationic liposomes (CL) was firstly prepared using Szoka reverse phase evaporation method. Then a series of CL/ASON complexes were obtained by mixing CL and ASON according to +/- charge ratio. The complexes of CFL and ASON were achieved based on fusing CL/ASON and Sendai virus. The physical and chemical properties of CFL were investigated thoroughly. The morphology of blank CL and CFL are round shape and homogeneous in size under the observationof transmission electron microscope. The mean particles size of blank CFL is 255.2nm and the I potential is 37.5mV when determined by Zetasizer 3000HS photon correlation spectroscopy. The size and I potential of CFL/ASON complexes are related to the +/- charge ratio. The loading efficiency of CFL was measured by spectrophotometric assay after separation using Microcon?centrifuge tube. ASON loading efficiency was 89.1% when the +/- charge ratio was 4:1.Below this values, the adsorption profile was found to be dependent on +/- charge ratio. In vitro, the ability of CFL in protecting ASON against DNase I was analyzed by...
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