transfection

摘要： In order to compare the transfection efficiency of lncRNA malat1 plasmid and lentivirus vectors in primary cultured rat DRG-derived satelite glial cells(SGCs).FISH was employed to detect the subcellular localization IncRNA-malat1l,qPCR was used to detect the expression of IncRNA-malat1 before and after transfection of the interference vector.It was found that malat1 was not silenced by IncRNA Smart silencers plasmid.qPCR results showed no significant difference in expression level of malat1 mRNA before and after transfection smart silencers plasmid of malat1 at 24 h,48h,3 d and7 d.The subcellular localization analysis found that malat1 was mainly located in the nucleus.It is speculated that it is difficult to achieve silencing of lncRNA located in the nucleus by applying interference technology of siRNA plasmid vector.qPCR results showed that the expression level of malat1 mRNA before and after malat1 transfection was significantly decreased at 24 h and 3 d compared with the normal group and the no-load group(P<0.05).In conclusion,it was suggested that the SGCs of DRG belonged to primary cells.

摘要： Human-induced pluripotent stem cells(iPSCs)are an accessible source of adult-derived,patient-specific pluripotent stem cells for use in basic research,drug discovery,disease modeling,and stem cell therapy.Improving the accessibility of methods to obtain iPSCs regardless of the cell source can enhance their clinical application.Therefore,our purpose is to report a simple protocol to obtain iPS-like cells from urine-derived renal epithelial cells(RECs)using different extracellular matrices and transfection reagents.In this study,we began by culturing urine-derived cells from healthy donors to establish a primary culture of renal epithelial cells,followed by their characterization.Subsequently,we generated iPS-like cells by transfecting renal epithelial cells(RECs)with vectors expressing Oct4,Sox2,L-Myc,Lin-28,and Klf4,and we compared the efficacy of different extracellular matrices and transfection reagents.The resultant iPS-like cells showed a human embryonic stem cell-like morphology and expressed the specific pluripotency markers Oct3/4,Nanog,Lin28,and Klf4.We concluded that Lipofectamine Stem Cell transfection reagent is more effective than FuGENE in obtaining iPS-like cells under the conditions tested.Moreover,the three matrices are similar in their efficiency of obtaining iPS-like cells.This report provides an experimental protocol for obtaining and generating iPS-like cells from urine samples for further cell therapy research on different human diseases.

摘要： Several toxic compounds are known to induce apoptosis in mammalian cell lines.The human neuroblastoma cells(SHSH-SY5Y)were exposed to the phosphatase inhibiting toxin okadaic acid(OA)or hydrogen peroxide(H2O2)to induce apoptosis as well as generate reactive oxygen species(ROS).Mitoxantrone(MXT)was used as a positive control for apoptosis.The SHSH-SY5Y cells were transfected with eukaryotic expression plasmid pHyPer-dMito encoding mitochondrial-targeted fluorescent or pHyPer-dCito encoding cytoplasmic-targeted fluorescent sensor for hydrogen peroxide(HyPer).The ERp57,also called GRP58(Glucose-regulated protein 58),is a stress protein induced in conditions like glucose starvation and viral infection.Recently ERp57 was shown to translocate from the endoplasmatic reticulum to the cell surface in anthracycline-induced apoptotic cells.ERp57 co-translocation together with calreticulin has been suggested to be crucial for recognizing tumor cells to induce immunogenic cell death.ERp57 translocation after exposure to okadaic acid was studied using immunofluorescence and confocal microscopy.These studies indicated that okadaic acid has induced the translocation of ERp57 to the cellular membrane.

摘要： Background:Cell transfection has the potential to transform gene therapy,potentially enabling the treatment of genetic diseases.We are developing a cell transfection approach that uses laser pulses and gold nanoparticles to induce transient holes in the cell membrane,thus allowing external material to pass into the cell before the membrane is healed.Our previous research has demonstrated the feasibility of perforating the cell membrane in vitro by irradiating(λ=532 nm,τ=6 ns)cancer cells previously incubated with gold-nanoparticles(100 nm).Our ultimate goal is to develop an optofluidic probe(needle-like)capable of performing simultaneous and precise delivery of a perforation mixture(nanoparticles and perforation indication dye)and laser pulses in vivo.We will present the initial validation of the technology with in vitro perforation of cancer cells.Methods:MDA-MB-231 cells were cultured in DMEM+GlutaMax(9%FBS,1%P/S).The medium was changed to Leibovitz’s L-15 for experimentation.100 nm gold nanoparticles and a perforation indicator dye(calcein,green dye)were placed on cells by pumping them through the optofluidic tip.The optofluidic tip was coupled to a nanosecond laser(λ=532 nm,τ=6 ns).Cells were irradiated with 5 laser pulses(Energy:15-38μJ)through the optrode tip at a distance of 50μm.Successful cell uptake was indicated by calcein uptake.Cells were incubated in 0.5%CO_(2) for one hour following irradiation.Then,propidium iodide(PI,red dye)was added to investigate cell death.The quantification of the perforation efficiency and viability was performed with fluorescence microscopy.Results:We have been able to successfully inject cells by pumping the perforation mixture through an optofluidic tip.The early quantitative results indicate that injection efficiencies are near 35%at the optimal fluence with cell viability near 90%.These efficiencies are similar to our previous results involving pre-incubation of cells with the perforation mixture.Conclusions:Our results show the feasibility of cell transfection using a particularly designed optofluidic probe(needle-like)for light and liquid delivery.The method does not involve pre-incubation of cells with the preformation mixture and thus brings the technology closer to in vivo applications.

摘要： Successful gene silencing by small interfering RNA (siRNA) requires efficient uptake of siRNA into targeted cells. For in vitro transfection of siRNA using cationic liposomes, two types of transfection method are currently being used: conventional (forward;Fw) and reverse (Rev) transfections. Here, to investigate an efficient siRNA transfection method using cationic liposomes, we compared the transfection efficiency of siRNA between Fw-transfection and Rev-transfection methods with various types of cationic liposomes. In Fw-transfection, siRNA/cationic liposomes complex (siRNA lipoplexes) was added to pre-plated cells. In contrast, Rev-transfection was performed by co-incubation of cells with siRNA lipoplexes in suspension. As a result, Rev-transfection with 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP)-based or cationic cholesterol derivative-based liposomes could deliver siRNA into the cells via efficient cellular association, and induce an improved gene silencing effect by siRNA compared with Fw-transfection. Furthermore, Rev-transfection did not show increased cytotoxicity compared with Fw-transfection. These findings suggested that Rev-transfection in suspension has better potential for efficient transfection of siRNA into cells with minimal toxicity.

摘要： Nucleic acids-based therapies have recently developed as next-generation agents for treating and preventing viral infection, cancer, and genetic disorders, but their use is still limited due to its relatively poor delivery into targeted cells. We designed and synthesized new amphiphilic amino acid derivatives (cysteine-based) of low molecular weight, formed by the same pentapeptide (AG2: WWCOO) N-acylated, with different hydrophobic chains containing from 12 to 18 carbons, named AG2-Cn (N), which dimerize by oxidation in the presence of pLenti-CMV-GFP Puro plasmid (P) in the respective gemini. We determined transfection efficiency, critical micelle concentration, particle size, ζ-potential and cytotoxicity for the derivatives obtained. We found that all the synthesized compounds were active for DNA delivery and had greater ability to transfect CHO-K1 cells. In particular, AG2-C18 is a promising carrier for gene delivery because it showed no cytotoxicity and its activity was greater than or equal to the commercial actives currently used.

摘要： The resorption of the transplanted fat over time limited the use of autologous fat for the reconstruction of soft tissue defect. Tissue engineering (TE) adipose with silk fibroin scaffold could be a promising substitute for soft tissue filling. In this study, we try to develop a tissue engineering adipose in vitro by seeding silk fibroin scaffold with human umbilical cord mesenchymal stem cells (hUCMSCs) after transfected with recombinant human insulin gene lentivirus. Our aim was to observe the effects of the insulin gene transfection on the adipogenesis of hUCMSCs when cultured with silk fibroin scaffolds. The hUCMSCs infected with recombinant lentiviral pLenti6.3-insulin-IRES-EGFP were seeded on silk fibroin scaffolds and cultured in adipogenic differentiation medium for 5 - 7 days. The expression of adipogenic gene PPARγ-2 was tested by RT-PCR after 7 days culture of adipogenic induction. The accumulation of cytoplasmic droplets of neutral lipids was assessed by Oil Red O staining. The RNA and protein expression of transfected insulin gene in hUCMSCs were detected by QPCR and western blot. The effect of recombinant lentivirus transfection on the growth and proliferation of hUCMSCs was observed by MTT test. We observed that the 2-ΔΔCt value of insulin gene expression of hUCMSCs in the transfected group was 300.25 times higher than that in the untransfected group. The western blot showed that a positive band was discerned at the site of a relative molecular mass of 8 × 103 Dalton in transfected group. After adipogenic culture for 7 days, under the fluorescent inverted phase-contrast microscope, after Oil Red O staining, a lot of adipocytes appeared in silk fibroin scaffold;round adipose droplets showed intracellularly;the size of the adipocytes was not homogenous, and the density of adipocytes in transfected group was significantly higher than that in untransfected group (P = 0.007, P 0.05). And there was also no significant difference in optical density (A) between cell group and cell-scalffold group (P = 0.066, P > 0.05). We concluded that insulin gene could obviously promote the adipogenic differentiation of hUCMSCs, and a tissue engineering adipose could be constructed by the silk fibroin scaffolds seeded with human insulin gene-modified hUCMSCs effectively in vitro.

摘要： In this paper, a novel series of bis [(aminoethyl)]-amine cationic lipid derivatives have been synthesized and identified to purity by NMR and Elemental analysis. B16-F0 cells were transfected with cationic lipid/pEGFP-N1 and cationic lipid/ß-gal lipoplexes complexed at +/- charge ratios of 1:1, 2:1, and 4:1. Dimyristoyl derivative showed highest activity at charge ratio 2:1 and both dimyristoyl and dioleoyl derivatives showed similar ß-gal activity at charge ratios 4:1. In 40 mM tris buffer pH 7.2 the dioleoyl derivative was able to fully complex with and retard pDNA at charge ratios above 2:1. None of the other lipid derivatives, dilauroyl, dimyristoyl, dipalmitoyl and distearoyl were able to fully neutralize the plasmid DNA at charge ratios similar to those used in the transfection experiment. The gel-to-liquid phase transition temperatures for dimyristoyl, dipalmitoyl and distearoyl were determined by a fluorescence anisotropy method to be 27.5°C, 32.5°C and 39°C, respectively. A gel-to-liquid crystalline phase transition temperature below 37°C, appears to be the crucial property that cationic lipids have to possess in order to mediate high levels of in vitro transfection activity in the absence of other helper lipids.

摘要： Transporter associated with antigen processing (TAP)-like (TAPL;ABCB9) is a half-type ABC transporter with sequence similarity to TAP1 and TAP2 that function in the ER membrane. To determine the cellular localization, TAPL and truncated forms of it were tagged with GFP at their car-boxyl termini. Intracellular localization of these fusion proteins was compared between transient and stable expression in CHO-K1 cells. When they were expressed transiently, the fluorescence of the fusion proteins was detected on the intracellular membrane, mainly in the ER, and all the fusion proteins, i.e., TAPL(M1 -A766)-GFP, TAPL(M1-S275)-GFP, TAPL(M1-K182 )-GFP, TAPL(M 1-R141)-GFP and TAPL(M1-G75), were co-localized with an ER marker, PDI. However, the fluorescence of all of them except for TAPL(M1-G 75)-GFP and TAPL(M1-S275)-GFP overlapped with a lysosome marker, cathepsin D, upon stable expression. Lysosomal localization was similarly observed with TAPL(M1- A766)-DsRed, which was stably expressed. These results suggest that TAPL is sorted to the lysosomal membrane when expressed stably in CHO-K1 cells. Furthermore, the lysosomal targeting signal may comprise the N-terminal four transmembrane helices since the N-terminal two transmembrane helices may not be enough to function as such a signal.