In the present study, packaging system composed of pAAV-CMV-GFP, pAAV-RC and pHelper were transfected into human embryonic kidney 293 cells (HEK293 cells) mediated by polyethyleneimine (PEI) to explore an optimal transfection condition. Different total plasmid DNA dosages (1, 2, 3, 4, 5, 6 μg) and different PEI/Plasmid ratios (1:1, 3:1, 5:1, 7:1) were tested with detection of green fluorescence protein (GFP) with ImagePro Plus6. 0 Software. Then transfection efficiency of the optimized transfection system was further observed for different time periods(12, 24, 36, 48, 60, 72 h). The results showed that total plasmid dosage of 4 μg/well with PEI/plasmid ratio of 3 : 1-5 : 1 was an efficient transfection condition. Transfection efficiency-time curve was an S-shaped curve. Transfection efficiency reached a plateau at 60 h after transfection. The optimized conditions for PEI-mediated transfection at the optimal time result in enhanced transfection efficiency of triple plasmid into HEK293 cells.
Green Fluorescent Proteins ; HEK293 Cells ; Humans ; Plasmids ; Polyethyleneimine ; Transfection ; methods

Apoptosis is a physiologically essential mechanism of cell and plays an important role in reducing the development and progression of tumors. The appealing strategy for cancer therapy is to target the lesions that induce apoptosis in cancer cells. Survivin, the smallest member of the mammalian inhibitors of the apoptosis protein family, is upregulated in various malignancies to protect cells from apoptosis. Survivin knockdown could induce cancer cell apoptosis and inhibit tumor-angiogenesis. Survivin expression would be silenced by microRNA (miRNA)-mediated RNA interference. However, noninvasive and tissue-specific gene delivery techniques remain absent recently and the utilizations of miRNA expression vectors have been limited by inefficient delivery technique, especially in vivo. On the other hand, safe and promising technologies of gene transfection would be valuable in clinical gene therapy. Successful treatment of gene transfer method would lead to a new and readily available approach in the anticancer research. Sonoporation is an alternative technique of gene delivery that uses ultrasound targeted microbubble destruction to create pores in the cell membrane. Based on our previous studies, in this article, we postulated that the transfection of miRNA could be mediated by the combination of sonoporation and polyethylenimine (PEI) which was one of the most effective poly-cationic gene vectors and enhance the endocytosis of plasmids DNA and hypothesized that the gene silencing and apoptosis induction with miRNA targeting human Survivin would be improved by this novel technique. In our opinion, this novel combination of sonoporation and PEI could enhance targeted gene delivery effectively and might be a feasible, novel candidate for gene therapy.
Genetic Therapy ; methods ; Humans ; Inhibitor of Apoptosis Proteins ; genetics ; MicroRNAs ; genetics ; Neoplasms ; therapy ; Polyethyleneimine ; chemistry ; Transfection ; methods

Polyethylenimine (PEI) is a kind of nanometer nonviral vector frequently applied in gene transfection. It is simple and easy to prepare and to modify and relatively safe compared to viral vectors. In recent years, PEI has been utilized in many research areas for gene delivery to stem cells in vitro or targeted gene delivery to cells in the brain. This review reveals that the cytotoxicity and low transfection efficiency of PEI requires to be improved. However brain-targeted modification indicates the promising prospect of PEI for gene therapy in cerebrovascular diseases.
Genetic Therapy ; Genetic Vectors ; Humans ; Nanostructures ; chemistry ; Polyethyleneimine ; chemistry ; Stem Cell Transplantation ; methods ; Transfection ; methods

AIMTo study polyethylenimine (PEI)-mediated in vivo gene transfection into testis cells and preliminary functional research of spermatogenic cell-specific gene NYD-SP12 using this method.

METHODSPEI/DNA complexes were introduced into the seminiferous tubules of mouse testes using intratesticular injection. Transfection efficiency and speciality were analyzed on the third day of transfection with fluorescent microscopy and hematoxylin staining. The long-lasting expression of the GFP-NYD-SP12 fusion protein and its subcellular localization in spermatogenic cells at different stages were analyzed with fluorescent microscopy and propidium iodide staining.

RESULTSWith the mediation of PEI, the GFP-NYD-SP12 fusion gene was efficiently transferred and expressed in the germ cells (especially in primary spermatocytes). Transfection into Sertoli cells was not observed. The subcellular localization of the GFP-NYD-SP2 fusion protein showed dynamic shifts in spermatogenic cells at different stages during spermatogenesis.

CONCLUSIONPEI can efficiently mediate gene transfer into spermatocytes. Thus, it might be useful for the functional research of spermatogenic-cell specific genes such as the NYD-SP12 gene. In our study, the NYD-SP12 protein was visualized and was involved in the formation of acrosome during spermatogenesis. Our research will continue into the detailed function of NYD-SP12 in spermatocytes.

Animals ; Green Fluorescent Proteins ; Homeodomain Proteins ; genetics ; physiology ; Humans ; Male ; Mice ; Polyethyleneimine ; Spermatogenesis ; physiology ; Transfection ; methods

OBJECTIVETo evaluate the feasibility of using iron oxide nanoparticles as gene vector and the effect of magnetic field on efficiency of transfection.

METHODSIron oxide nanoparticles were prepared by alkaline precipitation of divalent and trivalent iron chloride. The surface of iron oxide nanoparticles was modified by self-assembled poly-L-lysine to form particle complexes (IONP-PLL). Transfection was determined by delivering reporter gene, PGL2-control encoding luciferase, to different cell lines using IONP-PLL as vector. The effect of magnetic field on efficiency of transfection was determined using Nd-Fe-B permanent magnet.

RESULTSForeign gene could be delivered to various cell lines by IONP-PLL and expressed with high efficiency, but the transfection efficiency and time course varied in the different cell lines studied. Magnetic field could enhance the efficiency of transfection by 5 - 10 fold.

CONCLUSIONIONP-PLL can be used as a novel non-viral gene vector in vitro, which offers a basis for gene delivery in vivo.

Animals ; COS Cells ; Ferric Compounds ; administration & dosage ; Genetic Vectors ; Magnetics ; Polylysine ; administration & dosage ; Transfection ; methods

To optimize the operating variables that affect the transfection of antisense oligodeoxyribonucleotide (AS-ODNs) by insonated gas-filled lipid microbubbles, SF6-filled microbubbles were prepared by sonication-lyophilization method. An AS-ODNs sequence and a breast cancer cell line SK-BR-3 were used to define the various operating variables determining the transfection efficiency of SF6-filled microbubbles. Three levels of mixing speed, different durations of mixing and various delay time before ultrasound were examined, separately. Transfection efficiency was detected by fluorescence microscopy. Transfection results with and without incubation of AS-ODNs and microbubbles before mixing cells were compared. From the results, there is no significant difference between the transinfection efficiency with or without incubation of AS-ODNs and microbubbles before mixing cells. AS-ODNs transfection efficiency showed an increasing trend with mixing speed and mixing duration, but there is a negative relationship with delay time before ultrasound. The optimum parameters for AS-ODNs transfection by SF6-filled microbubbles were found at a mixing speed of 40-50 r x min(-1) for 30-60 s with less than 60 s delay before ultrasound. For a successful transfection, long time of incubation with gene is essential for normal nonviral vectors such as liposomes or cationic lipid-polymer hybrids, because these vectors depend on endocytosis and membrane fusion to realize transfection. Unlike liposomes and cationic lipid-polymer hybrids, gas-filled lipid microbubbles depend on sonorporation effect to realize transfection. Therefore, the incubation of gene and microbubbles before mixing cells may not be necessary. Ultrasound-mediated AS-ODNs transfection enhanced by gas-filled lipid microbubbles represents an effective avenue for gene transfer.
Cell Line, Tumor ; Green Fluorescent Proteins ; Humans ; Microbubbles ; Oligodeoxyribonucleotides, Antisense ; genetics ; Sulfur Hexafluoride ; Transfection ; methods ; Ultrasonics

This work was directed at obtaining a better gene carrier to improve the effects of gene delivery. Neutral liposomes made from cholesterol, lecithin and DOPE by reverse evaporation technique were used for encapsulating DNA-HAP complex which was made from DNA and optimized HAP. The sizes of complexes and the efficiency of encapsulation were detected. The efficiency of transfection into Hela cells was shown by observation of X-gal staining and measurement of transfection efficience. The average size of complexes was 643nm, the average encapsulating efficiency of DNA in microspheres reached 11.67%. These Lipid-Hydroxyapatite-DNA complex (LHD) could be transfected into mammalian cells. The Lipid-Hydroxyapatite-DNA complex prepared by reverse evaporation technique could be applied availably in DNA delivery system, and it gave another thinking to increase the gene transfection of non- viral genetic vector.
DNA ; administration & dosage ; Durapatite ; administration & dosage ; Genetic Therapy ; Lipids ; administration & dosage ; Transfection ; methods

AIMTo determine if the diagnostic ultrasound and self-made microbubbles could be used to increase gene transfection and expression in cardiac myocytes by means of the ultrasound-mediated microbubbles destruction.

METHODSThe perfluoropropane-exposed sonicated dextrose albumin(PESDA) microbubbles were made and mixed with indicated volume reporter gene encoding beta-galactosidase prior to gene transfection. Gene transfection into the cultured cardiac myocytes was performed by exposure to the various intense diagnostic ultrasound (1.3 MHz) in the presence of the gene-attached microbubbles. The calcium phosphate precipitation gene transfection was carried out alone or in combination with ultrasound-mediated destruction microbubbles. The cells were harvested 48 h after transfection and beta-galactosidase expression was detected by in situ staining and quantitive assay.

RESULTSCardiac myocytes exposed to ultrasound with PESDA induced significantly increase in gene expression (60-fold compared with naked plasmids transfection, P < 0.01). Moreover, it was found that the reporter gene expression not only related with ultrasound intension but also with the microbubbles concentration. In combination with calcium phosphate precipitation gene transfection, ultrasound-mediated destruction microbubbles resulted in more intense gene expression even 6 hours after calcium phosphate precipitation gene transfection.

CONCLUSIONThe ultrasonic destruction of gene-loaded microbubble is a highly effective gene transfer method, and it not only acts on the gene entry into cells, but also on the intracellular exogenous DNA expression.

Animals ; Gene Expression ; Genes, Reporter ; Myocytes, Cardiac ; cytology ; Plasmids ; Rats ; Rats, Wistar ; Transfection ; methods ; Ultrasonics

AIMTo pretreat sperm at various temperatures before exposure to human papillomavirus (HPV) 16 DNA fragments and to assess the efficiency of HPV carrier sperm to transfect cumulus cells.

METHODSCumulus cells from follicular aspirates were obtained, pooled and divided into culture dishes containing Sybr Gold-stained HPV DNA carrying sperm that were either pretreated at 4 degree C, 37 degree C or 40 degree C (n = 5). The cells were incubated in 5% CO(2) in air mixture at 37 degree C for 24 hours. The efficiency of sperm to take up fluorescent HPV DNA was determined at hour 0. After incubation, cumulus cell viability was assessed using the eosin method and the percentages of fluorescent cumulus cells determined.

RESULTSOver half of all the cumulus cells became fluorescent with the highest percentage in the 37 degree C group. Sperm pretreated at 4 degree C had the greatest amount of HPV DNA fragments. Total sperm motility was similar for the 3 pretreatment groups. There were no differences in cumulus viability among the groups.

CONCLUSIONSperm pretreated at 37 degree C transferred the greatest amount of fluorescent HPV DNA fragments to the cumulus cells. The HPV DNA was observed in the nuclear and cytoplasmic compartments. The data suggested the possibility of sperm as a vector for the transmission of HPV DNA to the cumulus cells surrounding ovulated oocytes, which might lead to early implantation failures.

DNA, Viral ; pharmacokinetics ; Humans ; Male ; Papillomaviridae ; genetics ; Spermatozoa ; physiology ; Temperature ; Transfection ; methods

To explore feasibility of real-time quantitative PCR in assessing efficiency of gene transfection, clonal PCR was employed to analyze efficiency of retroviral-mediated neo gene transfection in primary myoblast, simultaneous real-time PCR were performed for estimation of transfection efficiency; for measuring integrated gene copy number per cell, linear amplification mediated-PCR (LAM-PCR) and retroviral 5'LTR integration analysis also were used. The results showed that: (1) the data from clonal PCR are similar as that from real-time PCR in low efficiency of transfection (< 36%); but in high efficiency of transfection, it is significantly differentiation between clonal PCR and real-time PCR. (2) One copy of transduced gene per cell was observed in retroviral-mediated gene transfection in primary myoblast. It is concluded that real-time PCR can be used to estimate gene transfer vector in vivo, but it is not available for assessing gene transfection in vitro, because high efficiency of transfection could be obtained in most of gene transfection in vitro.
Animals ; Genetic Vectors ; genetics ; Polymerase Chain Reaction ; methods ; Retroviridae ; genetics ; Sequence Analysis, DNA ; Transfection