Green Fluorescent Protein Plasmid Research Articles

Tissue Tension and Strain as Indicators of Suction‐mediated Cutaneous DNA Transfection: A Parametric Study

AbstractCutaneous suction‐based transfection is a recently developed technique that is painless and simple‐to‐use for the delivery of DNA for nucleic‐acid‐based vaccines. The technique promises high efficiency for both antigen expression and immunogenicity as demonstrated in both animal studies and human clinical trials. To realize this promise, a parametric study and systematic evaluation of the efficacy of cutaneous suction as a transfection method is performed. Using Green Fluorescent Protein (GFP) plasmid expression as a transfection reporter in a rat model, the expression level as a function of both suction nozzle size and suction pressure is quantified. A numerical model is employed to compute skin deformation in terms of strain, which is used to correlate with GFP expression. Based on these results, two quantities, integrated total strain and tissue tension, are proposed as indicators of expression level that can be used to guide protocol development and optimization. These indicators are also discussed in relation to possible cellular uptake mechanisms.

Focused ultrasound on the substantia nigra enables safe neurotensin-polyplex nanoparticle-mediated gene delivery to dopaminergic neurons intranasally and by blood circulation

Neurotensin-polyplex nanoparticles provide efficient gene transfection of nigral dopaminergic neurons when intracerebrally injected in preclinical trials of Parkinson’s disease because they do not cross the blood–brain barrier (BBB). Therefore, this study aimed to open BBB with focused ultrasound (FUS) on the substantia nigra to attain systemic and intranasal transfections and evaluate its detrimental effect in rats. Systemically injected Evans Blue showed that a two-pulse FUS opened the nigral BBB. Accordingly, 35 μL of neurotensin-polyplex nanoparticles encompassing the green fluorescent protein plasmid (79.6 nm mean size and + 1.3 mV Zeta-potential) caused its expression in tyrosine hydroxylase(+) cells (dopaminergic neurons) of both substantiae nigrae upon delivery via internal carotid artery, retro-orbital venous sinus, or nasal mucosa 30 min after FUS. The intracarotid delivery yielded the highest transgene expression, followed by intranasal and venous administration. However, FUS caused neuroinflammation displayed by infiltrated lymphocytes (positive to cluster of differentiation 45), activated microglia (positive to ionized calcium-binding adaptor molecule 1), neurotoxic A1 astrocytes (positive to glial fibrillary acidic protein and complement component 3), and neurotrophic A2 astrocytes (positive to glial fibrillary acidic protein and S100 calcium-binding protein A10), that ended 15 days after FUS. Dopaminergic neurons and axonal projections decreased but recuperated basal values on day 15 after transfection, correlating with a decrease and recovery of locomotor behavior. In conclusion, FUS caused transient neuroinflammation and reversible neuronal affection but allowed systemic and intranasal transfection of dopaminergic neurons in both substantiae nigrae. Therefore, FUS could advance neurotensin-polyplex nanotechnology to clinical trials for Parkinson’s disease.

Amphiphilic polylactic acid-b-poly(N-(3-aminopropyl) methacrylamide) copolymers: Self-assembly to polymeric micelles for gene delivery

In this study, for the first time diblock copolymers of PLA-b-PAPMA with three different sizes were synthesized in order to fabricate cationic micelles. In this copolymer, p(APMA) block with hydrophilic cationic nature could serve as a nucleic acid condensation platform as well as the shell of micellar structure in the self-assembly process. The p(APMA) block was electrostatically complexed with nucleic acid, and formed a neutral or mildly positive charge micellar surface, thus providing the nanoparticles safety and stability. On the other hand, polylactic acid as a hydrophobic polymer in diblock copolymer structure formed core of micelles which could encapsulate hydrophobic therapeutics. The synthesized copolymers, PLA74-b-PAPMA14, PLA121-b-PAPMA22, PLA121-b-PAPMA103 were evaluated in terms of self-assembly capability, size, polydispersity index, plasmid condensation, transfection efficacy and cytotoxicity against C26 cells. Obtained results demonstrated low CMC values for all copolymers. PLA121-b-PAPMA103 diblock copolymer condensed green fluorescent protein plasmid at C/P 1 and higher, while other diblock copolymers were able to condense plasmid above C/P 70. The self-assembly structures of cationic micelles before and after plasmid condensation showed spherical morphology in SEM analysis while DLS data illustrated appropriate size (161.7 ± 8) and PDI (0.276) for PLA121-b-PAPMA103 diblock copolymer. It could be concluded that the cationic micelles with approximately the molecular weight ratio of hydrophilic block to total polymer mass of 60 % and larger than 50 % provided higher stability, condensation ability and transfection efficiency which could be attributed to the better self-assembly process and better amine groups exposure on the micellar surface.

Dose-dependent delivery of genes to the cerebral cortex via the nasal route

The use of nucleic acids to treat various brain diseases could offer new therapeutic modalities, providing the nucleic acids may be effectively delivered to areas of the brain using non-toxic vectors. In this study, we present evidence that genes may be successfully delivered in a dose-dependent manner via the nose, primarily to the cerebral cortex using a 6-O-glycolchitosan (GC) formulation of plasmid DNA. Positively charged (zeta potential = +13 - + 25 mV) GC-DNA nanoparticles of 100–500 nm in diameter with favourable cell biocompatibility were shown to deliver the reporter Green Fluorescent Protein (GFP) plasmid to the U87MG cell line and the resulting protein expression was not significantly different from that obtained with Lipofectamine 2000. On intranasal delivery of GC-luciferase-plasmid nanoparticles to Balb/ C mice at 4 doses, ranging from 0.02 to 0.1 mg/ kg, luciferase activity was observed qualitatively in intact mouse brains, 48 h after intranasal, using the IV-VIS visualisation. In further confirmation of brain delivery, dose-dependent protein expression was quantified in multiple brain areas 48 h after dosing; with protein expression seen mainly in the cerebral cortex and striatum and following expression levels: cerebral cortex = olfactory bulb > striatum > brain stem > mid brain = cerebellum. No protein expression was observed in the liver and lungs of dosed animals. GC-DNA protein expression was not significantly different to that observed with Lipofectamine 2000. These results demonstrate that GC-DNA nanoparticles are able to deliver genes preferably to specific brain regions such as the cerebral cortex and striatum; offering the possibility of using genes to treat a range of neurological disorders using a non-invasive method of dosing.

Genome engineering of human urine-derived stem cells to express lactoferrin and deoxyribonuclease.

Urine-derived stem cells (USCs) are adult kidney cells that have been isolated from a urine sample and propagated in tissue culture on gelatin-coated plates. Urine is a practical and completely painless source of cells for gene and cell therapy applications. We have isolated, expanded, and optimized transfection of USCs to develop regenerative therapies based on piggyBac transposon-modification. USCs from a healthy donor sample were isolated according to established protocols. Within two months, ten clones had been expanded, analyzed, and frozen. FACS analysis of individual clones revealed that all ten clones expressed characteristic USC markers (97-99% positive for CD44, CD73, CD90 and CD146; negative for CD31, CD34, and CD45).The isolated USCs were successfully differentiated along the osteogenic, adipogenic, and chondrogenic lineages, suggesting multipotent differentiation capacity. Additionally, the USCs were differentiated into podocytes positive for NEPHRIN, PODXL, and WT1. Transfection of USCs with a strongly-expressing GFP plasmid was optimized to achieve 61% efficiency in live cells using several commercially available lipophilic reagents. Transgene promoters were compared in five luciferase-expressing piggyBac transposons by IVIS imaging. The CMV promoter produced the highest luciferase signal, followed by EF1-α. Finally, HEK-293 and USCs were transfected with piggyBac transposons expressing lactoferrin and DNase1 for treatment of acute kidney injury associated with rhabdomyolysis. We found that both proteins were expressed in USCs and that lactoferrin was successfully secreted into the cell culture media. In conclusion, urine-derived stem cells represent a clinically relevant cell type that can express non-viral transgenes.

Use and Evaluation of a pES213-Derived Plasmid for the Constitutive Expression of gfp Protein in Pathogenic Vibrios: a Tagging Tool for In Vitro Studies.

Insertion of green fluorescent protein (GFP) into bacterial cells for constitutive expression is a powerful tool for the localization of species of interest within complex mixtures. Here, we demonstrate and evaluate the efficacy of the pES213-derived donor plasmid pVSV102 (gfp Knr) as a conjugative tool for the tagging of Vibrio and related species (termed vibrios). Using a triparental mating assay assisted by the helper plasmid pEVS104 (tra trb Knr), we successfully tagged 12 species within the Vibrionaceae family representing 8 of the proposed clades. All transconjugant strains demonstrated bright fluorescence and were readily differentiable within complex mixtures of nontagged cells. Plasmid retention was assessed using persistence and subculture experimentation. Persistence experiments evaluated plasmid loss over time for nonsubcultured samples inoculated into antibiotic-free media and sterile artificial seawater, whereas subculture trials evaluated plasmid loss following one to four subculture passages. Strong plasmid retention (≥80%) was observed in persistence experiments for all transconjugant strains for up to 48 h in both antibiotic-free media and artificial seawater with the exception of Vibrio cholerae, which showed a substantial decline in media after 24 h. Subculturing experiments also demonstrated strong plasmid stability, with all transconjugant strains showing ≥80% retention after four subculture passages. The results of this research suggest that pVSV102 is a stable GFP plasmid for the tagging of a broad range of vibrios. IMPORTANCE Prior research has suggested that the use of Aliivibrio fischeri-derived donor plasmids with the pES213 origin of replication may provide increased plasmid stability for the tagging of vibrios compared to Escherichia coli-derived p15A plasmids. Here, we present a structured protocol for conjugation-based tagging of vibrios using the pES213-derived plasmid pVSV102 and evaluate the plasmid stability of tagged strains. These methods and the resulting transconjugant strains provide important standardized tools to facilitate experimentation requiring the use of traceable vibrio strains. Furthermore, the determination of the species-specific plasmid stability provides an estimation of the anticipated level of plasmid loss under the given set of culture conditions. This estimation can be used to reduce the occurrence of experimental biases introduced by plasmid drift.

Mechanism of Polycaprolactone-Polyetherimide and pEGFP Nano-Composite and Bcl-2 Expression on Regulating Proliferation and Apoptosis of Cervical Carcinoma Cells

This study assessed mechanism of Polycaprolactone (PCL)-Polyetherimide (PEI) PCL-PEI and Enhanced green fluorescent protein plasmid (pEGFP) nano-composite on cervical carcinoma cells and associated Bcl-2 expression. The co-polymer of PCL-PEI was synthesized and pEGFP nano-composite was prepared. The PCL-PEI+pEGFP and empty carrier pEGFP C1 were transfected into Hela cells, which were divided into PCL-PEI group, CI (PCL-PEI+pEGFP and empty carrier pEGFP C1) group and NC group (normoal conctrast group). Proliferative condition of HeLa cells was detected with MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method, while invasive condition was detected with Transwell closet method. The cellular morphology was tested with Hoechst 33342 staining method and apoptotic condition was detected along with measurement of Bcl-2 and Bax. Results showed that, the quantity of GFP (green fluorescent protein) in the PCRL-PET Polycaprolactone (PCL)-Polyetherimide (PEI) (PCL-PEI) group was more than in NC group, and proliferative activity in PCL-PEI group was notably less than in the NC group. Moreover, no difference in proliferative activity was observed between NC and CI groups, and quantity of cross-membrane cells in PCL-PEI group was less than NC group without difference in the quantity of cross-membrane cells between NC group and CI group, and cell nucleus was intact in the NC and CI groups, with uniform IF color distribution and lack of apoptotic phenomenon. There were shrinking cells in the PCL-PEI group, and proliferation and apoptosis were restrained in the cervical carcinoma cells, which was prompted with PCL-PEI and pEGFP nano-composite. Finally, the expression of Bcl-2 in the cervical carcinoma cells was also restrained.

Charge-Converting Nanoemulsions as Promising Retinal Drug and Gene Delivery Systems.

Aim: This study aimed to develop phosphatase-responsive ζ potential converting nanocarriers utilizing polyphosphate-coated cell-penetrating peptide (CPP)-decorated nanoemulsions (NEs) as a novel gene delivery system to retinal cells. Methods: Poly-l-lysine (PLL) was first conjugated with oleylamine (OA) only at its carboxylic end to form the amphiphilic PLL–oleylamine (PLOA) conjugate. Afterward, NEs were loaded with PLOA prior to being coated with tripolyphosphate (TPP) to generate PLOA/TPP NEs. A plasmid containing a reporter gene for green fluorescent protein plasmid (pGFP) was complexed with cationic surfactants forming hydrophobic ion pairs that were loaded in the oily core of NEs. Phosphate removal, ζ potential conversion, and cytotoxicity of the system were evaluated. Cellular uptake and transfection efficiency were investigated in 661W photoreceptor-like cells via microscopic analysis, fluorescence spectroscopy, and flow cytometry. Results: Dephosphorylation of PLOA/TPP NEs triggered by alkaline phosphatase (ALP) resulted in the exposure of positive amine groups on the surface of NE droplets and a notable conversion of the ζ potential from −22.4 to +8.5 mV. Cellular uptake of PLOA/TPP NEs performed on 661W photoreceptor-like cells showed a 3-fold increase compared to control NEs. Furthermore, PLOA/TPP NEs also showed low cytotoxicity and high transfection efficacy with ∼50% of cells transfected. Conclusions: Polyphosphate-coated CPP-decorated NEs triggered by ALP could be a promising nanosystem to efficiently deliver drugs and genetic materials to photoreceptor-like cells and other retinal cells for potential treatments of retinal diseases.

Generating Human Induced Pluripotent Stem Cell Via Low-Dose Polyethylenimine-Mediated Transfection: An Optimized Protocol.

Human dermal fibroblasts (HDFs) can be reprogrammed through different strategies to generate human induced pluripotent stem cells (hiPSCs). However, most of these strategies require high-cost materials and specific equipment not readily accessible in most laboratories. Hence, liposomal and virus-based techniques can replace with polyethylenimine (PEI)-mediated transfection to overcome these challenges. However, few researchers have addressed the PEI's ability to transfect HDFs. This study used PEI reagent to transfer oriP/EBNA1-based vector into HDFs to produce hiPSC lines. We first described conditions allowing the efficient transfection of HDFs with low cytotoxicity and without specific types of equipment and optimized several parameters relevant to the transfection procedure. We then monitored the effect of different N/P ratios on transfection efficiency and cytotoxicity using flow cytometry and fluorescent microscopy. By the results, we found that transfection efficiency was greatly affected by plasmid DNA concentration, PEI concentration, order of combining reagents, serum presence in polyplexes, and the duration of serum starvations. Moreover, using the optimized condition, we found that the N/P ratio of 3 achieved the highest percentage of HDFs positive for green fluorescent protein plasmid (∼40%) with minimal cell toxicity. We finally generated hiPSCs using the optimized protocol and oriP/EBNA1-based vectors. We confirmed hiPSC formation by characterizing tests: alkaline phosphatase staining, immunocytochemistry assay, real-time PCR analysis, in vitro differentiation into three germ layers, and karyotyping test. In conclusion, our results indicated that 25 kDa branched PEI could efficiently transfect HDFs toward generating hiPSCs via a simple, cost-effective, and optimized condition.

Development of targeted gene delivery system based on liposome and PAMAM dendrimer functionalized with hyaluronic acid and TAT peptide: In vitro and in vivo studies.

The development of gene delivery systems is essential to improve their transfection efficiency and cytotoxicity. Combination of lipid and polymeric nanoparticles with the characteristics of both systems have been considered as a next-generation gene delivery platform. In the current study, we designed a novel and efficient targeted gene delivery system based on liposome and PAMAM dendrimer in cancer cells. Two polymeric formulations containing polyamidoamine-TAT (PAMAM-TAT) and PAMAM-TAT-Hyaluronic acid (HA) and two lipopolymeric carriers including PAMAM-TAT-Liposome and PAMAM-TAT-HA-Liposome were complexed with the enhanced green fluorescent protein (EGFP) plasmid and then evaluated in terms of physicochemical characteristics. The cytotoxicity and transfection efficiency of these synthetized carriers were accomplished against murine colon carcinoma cell line (C26). The biodistribution of polyplexes and lipoployplexes was also evaluated in the C26 tumor bearing mice. The results showed no significant toxicity for all designed nanoparticles (NPs) in C/P4. The highest gene expression was observed using lipopolyplex PAMAM-TAT-HA-Liposome in C/P4 (ratio polymer/DNA; wt/wt). Biodistribution study demonstrated more aggregation of targeted lipopolyplex in tumor cells than other nanoparticles (NPs). It could be concluded that the developed targeted lipopolymeric complex could serve as promising nanotherapeutic system for gene therapy.

Effect of molecular weight of chitosan on the physicochemical, morphological, and biological properties of polyplex nanoparticles intended for gene delivery

The use of viral vectors in gene therapy has many disadvantages that have been widely described. The development of new nonviral vectors using safe polymers such as chitosan provides a viable alternative. Chitosan molecular weight and nitrogen/phosphorus (N/P) ratio are key factors that determine the shape, size, and surface charge of polyplex nanoparticles (NPs) assembled by complex coacervation for gene therapy; and at the same time, their transfection efficiency is affected by these characteristics, besides the cell line used for transfection. However, there are some inconsistencies in previous reports about the effect of chitosan molecular weight on all these parameters. Enhanced Green Fluorescent Protein plasmid (pEGFP-N1) and two molecular weight (MW) chitosan (20.6 and 57.5 kDa) with a high degree of deacetylation (≥85%) were used to design and assembly nanoparticles by complex coacervation with N/P ratios of 43 and 8. NPs were characterized determining morphology by Scanning Electron Microscopy (SEM), size by Dynamic Light Scattering (DLS) and zeta-potential by Laser-Doppler velocimetry (LDV). Also, biological functionality was assessed by in vitro transfection assays. NPs assembled using the lowest MW chitosan (20.6NPs) and N/P ratio = 8 had spherical shape, smaller mean size and polydispersity index (119 ± 20 nm; 0.257, respectively), and lower zeta-potential (17.65 ± 1.21 mV). Moreover, no significant difference was observed in size, polydispersity index and zeta-potential after 30 days of storage, in contrast with NPs assembled using the 57.5 kDa chitosan (57.5NPs). In vitro transfection assays using two cervical cancer cell lines (HeLa and SiHa) showed that 20.6NPs leaded to a higher expression of Green Fluorescent Protein (GFP) in contrast to 57.5NPs for both cell lines, and expression in HeLa cells was higher than in SiHa cell line. It was confirmed that transfection efficiency depends on all these physical parameters given by MW of chitosan, cell physiology, and the addition of fetal bovine serum in the transfection formulation. These results indicate that low MW chitosan and a low N/P ratio are more suitable to design chitosan-based nonviral vectors for gene therapy, given that physicochemical and biological properties, so as the stability of these NPs are better that those formulated with chitosan of higher MW.

Optimization of Protoplast Isolation and Transformation for a Pilot Study of Genome Editing in Peanut by Targeting the Allergen Gene Ara h 2.

The cultivated peanut (Arachis hypogaea L.) is a legume consumed worldwide in the form of oil, nuts, peanut butter, and candy. Improving peanut production and nutrition will require new technologies to enable novel trait development. Clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9 (CRISPR–Cas9) is a powerful and versatile genome-editing tool for introducing genetic changes for studying gene expression and improving crops, including peanuts. An efficient in vivo transient CRISPR–Cas9- editing system using protoplasts as a testbed could be a versatile platform to optimize this technology. In this study, multiplex CRISPR–Cas9 genome editing was performed in peanut protoplasts to disrupt a major allergen gene with the help of an endogenous tRNA-processing system. In this process, we successfully optimized protoplast isolation and transformation with green fluorescent protein (GFP) plasmid, designed two sgRNAs for an allergen gene, Ara h 2, and tested their efficiency by in vitro digestion with Cas9. Finally, through deep-sequencing analysis, several edits were identified in our target gene after PEG-mediated transformation in protoplasts with a Cas9 and sgRNA-containing vector. These findings demonstrated that a polyethylene glycol (PEG)-mediated protoplast transformation system can serve as a rapid and effective tool for transient expression assays and sgRNA validation in peanut.

Nano-optical method for transforming a single yeast cell using exogenous genes.

We report a highly efficient nano-optical method for transforming a single yeast cell using exogenous genes. It used laser tweezers or micromanipulators to immobilize the cell immersed in a DNA solution and created a transient nano-sized hole on its cell wall concurrently with laser scissors to deliver nano moles of DNA into the cell. With this method, one can directly transfer the naked DNA of exogenous genes into yeast cells for transformation. We successfully transformed S. cerevisiae yeasts respectively with GFP (Green Fluorescent Protein) plasmid and the nucleic acid extraction of a bacteria GF1 from the gut of Coptotermes formosanus termites. The experimental results demonstrated that the recombinants had high survival rate and transformation efficiency (28%). The recombinant GFP-yeast system showed green fluorescence for generations. GF1 DNA sequences were incorporated into the yeast genome as a heritable component with stable expression for multi-generations so that the recombinant GF1-yeast had a strong capability of digesting biomass as GF1. Our method would apply to different cells with cell walls for various gene transformations.

HIV-1 Tat induced microglial EVs leads to neuronal synaptodendritic injury: microglia-neuron cross-talk in NeuroHIV.

Activation of microglial NLRP3 inflammasome is an essential contributor to neuroinflammation underlying HIV-associated neurological disorders (HAND). Under pathological conditions, microglia-derived-EVs (MDEVs) can affect neuronal functions by delivering neurotoxic mediators to recipient cells. However, the role of microglial NLRP3 in mediating neuronal synaptodendritic injury has remained unexplored to date. In the present study, we sought to assess the regulatory role of HIV-1 Tat induced microglial NLRP3 in neuronal synaptodendritic injury. We hypothesized that HIV-1 Tat mediated microglia EVs carrying significant levels of NLRP3 contribute to the synaptodendritic injury, thereby affecting the maturation of neurons. To understand the cross-talk between microglia and neuron, we isolated EVs from BV2 and human primary microglia (HPM) cells with or without NLRP3 depletion using siNLRP3 RNA. EVs were isolated by differential centrifugation, characterized by ZetaView nanoparticle tracking analysis, electron microscopy, and western blot analysis for exosome markers. Purified EVs were exposed to primary rat neurons isolated from E18 rats. Along with green fluorescent protein (GFP) plasmid transfection, immunocytochemistry was performed to visualize neuronal synaptodendritic injury. Western blotting was employed to measure siRNA transfection efficiency and the extent of neuronal synaptodegeneration. Images were captured in confocal microscopy, and subsequently, Sholl analysis was performed for analyzing dendritic spines using neuronal reconstruction software Neurolucida 360. Electrophysiology was performed on hippocampal neurons for functional assessment. Our findings demonstrated that HIV-1 Tat induced expression of microglial NLRP3 and IL1β, and further that these were packaged in microglial exosomes (MDEV) and were also taken up by the neurons. Exposure of rat primary neurons to microglial Tat-MDEVs resulted in downregulation of synaptic proteins- PSD95, synaptophysin, excitatory vGLUT1, as well as upregulation of inhibitory proteins- Gephyrin, GAD65, thereby implicating impaired neuronal transmissibility. Our findings also showed that Tat-MDEVs not only caused loss of dendritic spines but also affected numbers of spine sub-types- mushroom and stubby. Synaptodendritic injury further affected functional impairment as evidenced by the decrease in miniature excitatory postsynaptic currents (mEPSCs). To assess the regulatory role of NLRP3 in this process, neurons were also exposed to Tat-MDEVs from NLRP3 silenced microglia. Tat-MDEVs from NLRP3 silenced microglia exerted a protective role on neuronal synaptic proteins, spine density as well as mEPSCs. In summary, our study underscores the role of microglial NLRP3 as an important contributor to Tat-MDEV mediated synaptodendritic injury. While the role of NLRP3 in inflammation is well-described, its role in EV-mediated neuronal damage is an interesting finding, implicating it as a target for therapeutics in HAND.

Development of ATP13A2-deficient In vitro Model for PARK9 Parkinson’s Disease

Background: PARK9 familial Parkinson’s disease (PD) is caused by a loss-of-function mutation in the ATP13A2 gene in which the mutation impairs the autophagic-lysosomal degradation pathway and induces intraneuronal accumulation of alpha-synuclein. RNA interference has been a useful tool in generating in vitro knockdown model to study the physiological role of the gene. However, the availability of a validated ATP13A2-deficient in vitro model is limited. Objective: This study aimed to develop the ATP13A2-deficient PD model by delivering ATP13A2 siRNA into neuroblastoma cells using carbonate apatite nanoparticles (CA NPs). Methods: CA NPs were fabricated using different concentrations of calcium chloride and characterised in the presence or absence of ATP13A2 siRNA. Time-dependent stabilities of CA NPs and CA NPs-associated siRNA (CA-siRNA) complex were evaluated by pH, turbidity, size, and zeta potential measurements. The dissolution abilities at acidic conditions of both complexes were investigated. Following that, green fluorescence protein (GFP) and four different siRNAs targeting ATP13A2 (siRNA_5, 6, 7, and 8) were transfected to cells with the fabricated CA NPs. Western blot was performed to determine the knockdown effect of the four siRNAs. Results: It was found that 4 mM calcium chloride was ideal for CA NP formation, while an incubation time of 48 hours was required to maintain the stability of nanoparticles. Successful transfection was confirmed by detection of fluorescence signal from the GFP plasmid and the subsequent silencing of this signal by transfecting GFP siRNA. Western blot analysis revealed that ATP13A2 protein expression was significantly reduced to 20% upon transfection with 20 nM of siRNA_5. Conclusion: ATP13A2-deficient PD model was successfully developed.

High-Throughput and Dosage-Controlled Intracellular Delivery of Large Cargos by an Acoustic-Electric Micro-Vortices Platform.

A high‐throughput non‐viral intracellular delivery platform is introduced for the transfection of large cargos with dosage‐control. This platform, termed Acoustic‐Electric Shear Orbiting Poration (AESOP), optimizes the delivery of intended cargo sizes with poration of the cell membranes via mechanical shear followed by the modulated expansion of these nanopores via electric field. Furthermore, AESOP utilizes acoustic microstreaming vortices wherein up to millions of cells are trapped and mixed uniformly with exogenous cargos, enabling the delivery of cargos into cells with targeted dosages. Intracellular delivery of a wide range of molecule sizes (<1 kDa to 2 MDa) with high efficiency (>90%), cell viability (>80%), and uniform dosages (<60% coefficient of variation (CV)) simultaneously into 1 million cells min−1 per single chip is demonstrated. AESOP is successfully applied to two gene editing applications that require the delivery of large plasmids: i) enhanced green fluorescent protein (eGFP) plasmid (6.1 kbp) transfection, and ii) clustered regularly interspaced short palindromic repeats (CRISPR)‐Cas9‐mediated gene knockout using a 9.3 kbp plasmid DNA encoding Cas9 protein and single guide RNA (sgRNA). Compared to alternative platforms, this platform offers dosage‐controlled intracellular delivery of large plasmids simultaneously to large populations of cells while maintaining cell viability at comparable delivery efficiencies.

High‐Efficient and Dosage‐Controllable Intracellular Cargo Delivery through Electrochemical Metal–Organic Hybrid Nanogates

Hollow nanostructures combined with electroporation are potentially valuable in interdisciplinary fields due to their ability to transport versatile cargos into adhesive cells. However, they require voltages over 1.5 V to electroporate the physical barrier of the cell membrane inducing cell death and differentiation processes. Intracellular delivery is exhibited using a metal–organic hybrid nanotube (NT) stamp that physically inserts into the cells and subsequently injects versatile molecules at an extremely low voltage of ±50 mV (less than membrane potential). The hybrid NTs consist of Au NTs polymerizing electrochemically 3,4‐ethylenedioxythiophene monomer and supportive polycarbonate membrane. The hybrid stamp improves the cell viability by 94% for a 30 min physical insertion while decreasing the cell viability to 1% using the original Au NTs. Furthermore, the hybrid stamp acts as an electrochemical gate that can open the pore at ±50 mV to transport small molecules of calcein dye with high efficiency (99%) and viability (96.8%). The hybrid nanogate can also transport large molecules of green fluorescent protein (GFP) with 84% efficiency and 98.5% viability, and GFP plasmid at a transfection rate of ≈10%. Thus, the present hybrid stamping can potentially deliver versatile molecules into adhesive cells.

Construction and investigation of plasmid-induced effects on growth of GFP-expressing Salmonella strains

Background: Bacteria such as the Salmonella species had been extensively studied not only for its mechanism of pathogenicity, but for its beneficial utilisation in bacterial-mediated tumour therapy. Genetically modified bacterial strain, BDLA Salmonella Agona (BDLA S. Agona) had shown great promise as tumour targeting and suppressing agent. By, constructing green fluorescent protein (GFP) expressing of this strain, it would be beneficial as it could be used to further study the interaction of the BDLA S. Agona strain with various cancerous cells and the host at the systemic level. However, GFP plasmid-induced strains may exhibit growth defects, and this was investigated in this study. Methods: The GFP-transformed Salmonella strains were constructed, and the replication rate of the strains were investigated using the BacterioScan™ 216R instrument. The replication rate between the strains was compared from the 24-hour data collected and analysed as growth curves. The 24-hour growth curves were constructed using the Log CFU/mL and OD650 data collected by the instrument. Results: It was observed from the growth curves that the transformation of the GFP plasmid into different Salmonella strains did not affect the replication rate of the bacteria. Discussion and Conclusion: This finding answers the objective of the study, and it was concluded that incorporation of the GFP plasmid does not cause any negative effect on bacterial growth. GFP-transformed Salmonella, specifically the BDLA S. Agona strain, could be utilised as a powerful tool for future studies on the mechanism of tumour suppression and real-time in vivo biodistribution of the strain.

Construction and investigation of plasmid-induced effects on growth of GFP-expressing Salmonella strains

Background: Bacteria such as the Salmonella species had been extensively studied not only for its mechanism of pathogenicity, but for its beneficial utilisation in bacterial-mediated tumour therapy. Genetically modified bacterial strain, BDLA Salmonella Agona (BDLA S. Agona) had shown great promise as tumour targeting and suppressing agent. By, constructing green fluorescent protein (GFP) expressing of this strain, it would be beneficial as it could be used to further study the interaction of the BDLA S. Agona strain with various cancerous cells and the host at the systemic level. However, GFP plasmid-induced strains may exhibit growth defects, and this was investigated in this study. Methods: The GFP-transformed Salmonella strains were constructed, and the replication rate of the strains were investigated using the BacterioScan™ 216R instrument. The replication rate between the strains was compared from the 24-hour data collected and analysed as growth curves. The 24-hour growth curves were constructed using the Log CFU/mL and OD650 data collected by the instrument. Results: It was observed from the growth curves that the transformation of the GFP plasmid into different Salmonella strains did not affect the replication rate of the bacteria. Discussion and Conclusion: This finding answers the objective of the study, and it was concluded that incorporation of the GFP plasmid does not cause any negative effect on bacterial growth. GFP-transformed Salmonella, specifically the BDLA S. Agona strain, could be utilised as a powerful tool for future studies on the mechanism of tumour suppression and real-time in vivo biodistribution of the strain.

Ultrasound-Targeted Microbubble Destruction Enhances the Inhibitive Efficacy of miR-21 Silencing in HeLa Cells.

BackgroundPrevious studies have shown that miR-21 upregulation is related to the aggressive development of cervical cancer. Ultrasound-targeted microbubble destruction (UTMD) is a method that increases the absorption of targeted genes or drugs by cells. We focus on the role of UTMD-mediated miR-21 transfection in HeLa cells, a cervical cancer cell line.Material/MethodsThe effects of different ultrasound intensities on the transfection efficiency of miR-21-enhanced green fluorescent protein (EGFP) and miR-21 inhibitor-EGFP plasmids were determined by flow cytometry. The effects of UTMD-mediated miR-21 transfection on HeLa cell proliferation, apoptosis, migration, and invasion were measured by CCK-8, flow cytometry, wound healing experiments, and transwell migration assay, respectively. Western blot and real-time quantitative PCR were used to detect the expression of tumor-related genes.ResultsWhen the ultrasound intensity was 1.5 W/cm2, the miR-21 plasmid had the highest transfection efficiency. Exogenous miR-21 promoted cell proliferation, migration, and invasion, and inhibited cell apoptosis in HeLa cells. Treatment of cells with UTMD further enhanced the effects of miR-21-EGFP and miR-21 inhibitor-EGFP. In addition, miR-21 overexpression significantly increased the expression of p-Akt, Akt, Bcl-2, Wnt, β-catenin, matrix metalloprotein-9 (MMP-9), and epidermal growth factor (EGFR) levels, and decreased Bax expression. The regulatory role of miR-21 inhibitor-EGFP was opposite to that of miR-21-EGFP. After UTMD, miR-21-EGFP and miR-21 inhibitor-EGFP had more significant regulatory effects on these genes.ConclusionsOur research revealed that an ultrasound intensity of 1.5 W/cm2 is the best parameter for miR-21 transfection. UTMD can enhance the biological function of miR-21 in HeLa cells, and alter the effect of miR-21 on apoptosis, metastasis, and phosphorylation genes.