Search Results (22)

Bats are important reservoirs of zoonotic pathogens and valuable models for studying antiviral tolerance and neuroinflammation within a One Health framework. However, chiropteran neural 2D-in vitro models remain limited. Here, we established and characterized the first chiropteran primary (CpBCs) and immortalized (CiBCs) cell lines from Hypsugo savii species. To overcome the limited lifespan of CpBCs, immortalization strategies based on human telomerase reverse transcriptase (hTERT) and Simian virus 40 large T antigen (SV40) were evaluated. Electroporation-mediated transfection with SV40 successfully generated CiBCs, whereas liposome-mediated and hTERT-based approaches were unsuccessful. RNA sequencing revealed marked transcriptional changes comparing CiBCs with CpCBs, such as the upregulation of pathways related to cell cycle progression, DNA replication, and proliferation in CiBCs, together with the downregulation of apoptosis, inflammatory signaling, and immune-related pathways. Immortalized cells also exhibited enrichment of neural stem cell-like and cancer-associated signatures, suggesting partial dedifferentiation induced by SV40-mediated immortalization. Overall, this study provides a novel chiropteran brain-derived 2D-in vitro platform for investigating bat neurobiology, host–pathogen interactions, viral tolerance, and neurotropic infectious diseases relevant to emerging zoonoses. Full article

The growth and development of adipose tissue in sheep tails are closely associated with adipocyte proliferation and differentiation. However, the functional role and regulatory mechanisms of the FGF8 gene in sheep preadipocytes remain incompletely understood. In this study, liposome-mediated transfection was employed to overexpress the FGF8 gene and assess its effects on the proliferation and differentiation of sheep preadipocytes. The results of the Cell Counting Kit-8 (CCK-8) assay indicated that the overexpression of FGF8 promoted preadipocyte viability of preadipocytes. Subsequently, this was verified by RT-qPCR analysis, which showed significant upregulation of proliferation marker genes, including CyclinB (p < 0.001) and Proliferating Cell Nuclear Antigen (PCNA) (p < 0.01), while CyclinD mRNA expression increased compared with the control group, though the increase was not statistically significant. During adipogenic induction, the mRNA expression levels of differentiation markers, such as Peroxisome Proliferator-Activated Receptor Gamma (PPARγ), CCAAT/Enhancer Binding Protein Alpha (C/EBPα), Adipocyte type Fatty Acid Binding Protein 4 (FABP4), and Adiponectin, initially increased and then decreased. The expression of all four markers peaked on day 10 of induction, exceeding levels observed in the control group. In vitro experiments showed that FGF8 affected the proliferation and differentiation of sheep preadipocytes and may be involved in the regulation of tail fat deposition. Full article

Hepatitis E virus (HEV) is a zoonotic pathogen that can infect pregnant women and cause adverse pregnancy outcomes, including miscarriage and preterm delivery. The previous study demonstrated that HEV genotype 3 (HEV-3) inhibits complete autophagic flux in both mouse placental tissue and human trophoblast cells (JEG-3), evidenced by reduced expression of ATG proteins (including LC3, Beclin1, ATG4B, ATG5, and ATG9A) and accumulation of p62. However, the specific regulatory pathway involved remains unclear. Thus, eukaryotic expression vectors for HEV open reading frames (ORFs) were constructed, and ORF2 and ORF3 proteins were transiently overexpressed in JEG-3 cells via liposome transfection. While both ORF2 and ORF3 significantly reduced LC3B protein levels (p < 0.01), only ORF2 induced p62 accumulation (p < 0.01), indicative of autophagic inhibition, which indicates that ORF2 was the key viral protein mediating autophagy suppression in JEG-3. The results of WB and RT-qPCR showed that ORF2 suppressed the PI3K/Akt/mTOR pathway while enhancing nuclear translocation of TFEB (p < 0.01) and AMPK phosphorylation (p < 0.01), suggesting paradoxical activation of upstream autophagy regulators. Through co-transfection of mCherry-LC3 with ORF2, co-localization studies, and AlphaFold 3-based intermolecular interaction predictions, we propose that ORF2 directly binds LC3B to block autophagosome formation. Finally, co-immunoprecipitation confirmed physical interaction between HEV ORF2 and LC3B, elucidating the molecular mechanism of HEV-induced autophagy suppression in trophoblasts. These findings reveal the molecular mechanism by which HEV inhibits autophagy leading to miscarriage in mice, providing new insights into HEV-induced reproductive damage. Full article

The blood–brain barrier (BBB) restricts the entry of therapeutic agents into the brain cardiovascular regulatory region, potentially contributing to drug-resistant hypertension. Objective: The objective of this study was to overcome this limitation by modifying PEGylated liposomes with transferrin (Tf) to facilitate Tf receptor binding at the BBB and penetratin (Pen), a cell-penetrating peptide, to enhance neuronal uptake. Methods: This study evaluated the efficacy of Tf-Pen-liposomes in delivering angiotensin-converting enzyme 2 (ACE2) or EGFP (control) genes across the BBB in rats. In addition, the therapeutic effect of intravenous administration of Tf-Pen-Lip carrying plasmid DNA encoding ACE2 (Tf-Pen-Lip-pACE2) was tested in a neurogenic hypertension model induced by intracerebroventricular (ICV) infusion of angiotensin II (Ang II) via osmotic pump implantation and brain cannulation. Results: Conjugation with Tf and Pen significantly enhanced liposome-mediated gene transfection in cultured cells and increased transport across an in vitro BBB model. In vivo, intravenous administration of Tf-Pen-Lip-pACE2 or Tf-Pen-Lip-pGFP successfully elevated ACE2 or EGFP expression, respectively, in the hypothalamic paraventricular nucleus (PVN). Chronic ICV infusion of Ang II produced a sustained increase in blood pressure and heart rate, accompanied by sympathetic overactivation and elevated arginine vasopressin (AVP) secretion, hallmarks of neurogenic hypertension. Notably, intravenous Tf-Pen-Lip-pACE2 treatment dramatically attenuated Ang II–induced neurogenic hypertension, whereas Tf-Pen-Lip-pGFP had no effect on pressor responses, sympathetic activity, or AVP secretion. Conclusions: This dual-functionalized liposomal delivery system effectively transported the ACE2 gene across the BBB into the brain, increased ACE2 expression, and markedly attenuated neurogenic hypertension following systemic administration. Full article

Background/Objectives: Co-transfection of multiple DNAs is important to many research and therapeutic applications. While the optimization of single plasmid transfection is common, multiple plasmid co-transfection analyses are limited. Here we provide empirical data regarding multiple plasmid co-transfection while altering the number of species of plasmids transfected (up to four different plasmids) and the amount of plasmids/cell using the two most common non-viral techniques, electroporation and lipofection. Methods: A549 human lung epithelial cells were transfected using lipofectamine 2000 or electroporation with combinations of plasmids, each expressing one of four different fluorescent proteins from the CAGG promoter. Twenty-four hours later, cells were analyzed by spectral flow cytometry to determine the number of cells expressing each fluorescent protein and the amount of fluorescent signal of each protein in a cell. Results and Conclusions: For electroporation, while the fraction of cells expressing plasmids increased with increasing amounts of DNA, increasing the number of plasmid species did not alter the fraction of expressing cells and had no effect on levels of expression in individual cells. By contrast, for lipofection, the fraction of cells expressing plasmids was not affected by the amount of DNA added but both the fraction of cells expressing and the level of protein produced in these cells decreased for each plasmid species as the number of delivered species increased. For both lipofection and electroporation after single plasmid transfection, the expressing cells had greater numbers of plasmid copies/cell than non-expressing cells. Multiple plasmid lipofection resulted in more plasmid copies/cell in co-expressing than non-expressing cells. Multiple plasmid electroporation was the inverse of this with fewer plasmid copies/cell in co-expressing than non-expressing cells. Full article

Milk fat is an important nutritional component and flavor substance in dairy products. Its content and composition directly affect the nutritional value, processing characteristics, and economic benefits of dairy products. Therefore, an in-depth exploration of the molecular mechanisms that influence milk protein synthesis holds profound significance for dairy farming and dairy production. Molecular biology techniques were used to construct CDKN1A overexpression and interference vectors. Using BMECs (bovine mammary epithelial cells) as the experimental model, the vectors were transfected into the cells via liposome mediation to investigate the effect of CDKN1A on the expression of genes related to milk protein synthesis. The results showed that the CDKN1A overexpression and interference vectors were successfully constructed, and the overexpression of CDKN1A reduced milk protein synthesis, and the interference of CDKN1A enhanced milk protein synthesis. This finding provides an important theoretical basis for dairy farming and dairy production. By regulating the expression level of CDKN1A, it is possible to achieve precise control of milk protein yield in dairy cows. It also offers a potential target for the development of new feed additives or drugs. These additives or drugs can promote milk protein synthesis by regulating the activity of CDKN1A, providing new strategies and methods for the sustainable development of the dairy industry. Full article

Transfection agents play a crucial role in facilitating the uptake of nucleic acids into eukaryotic cells offering potential therapeutic solutions for genetic disorders. However, progress in this field needs the development of improved systems that guarantee efficient transfection. Here, we describe the synthesis of a set of chemical delivery agents (TRIFAPYs) containing alkyl chains of different lengths based on the 1,3,5-tris[(4-alkyloxy-1pyridinio)methyl]benzene tribromide structure. Their delivery properties for therapeutic oligonucleotides were evaluated using PolyPurine Reverse Hoogsteen hairpins (PPRHs) as a silencing tool. The binding of liposomes to PPRHs was evaluated by retardation assays in agarose gels. The complexes had a size of 125 nm as determined by DLS, forming well-defined concentrical vesicles as visualized by Cryo-TEM. The prostate cancer cell line PC-3 was used to study the internalization of the nanoparticles by fluorescence microscopy and flow cytometry. The mechanism of entrance involved in the cellular uptake was mainly by clathrin-mediated endocytosis. Cytotoxicity analyses determined the intrinsic toxicity caused by each TRIFAPY and the effect on cell viability upon transfection of a specific PPRH (HpsPr-C) directed against the antiapoptotic target survivin. TRIFAPYs C12-C18 were selected to expand these studies in the breast cancer cell line SKBR-3 opening the usage of TRIFAPYs for both sexes and, in the hCMEC/D3 cell line, as a model for the blood–brain barrier. The mRNA levels of survivin decreased, while apoptosis levels increased upon the transfection of HpsPr-C with these TRIFAPYs in PC-3 cells. Therefore, TRIFAPYs can be considered novel lipid-based vehicles for the delivery of therapeutic oligonucleotides. Full article

Laboratory production of recombinant mammalian proteins, particularly antibodies, requires an expression pipeline assuring sufficient yield and correct folding with appropriate posttranslational modifications. Transient gene expression (TGE) in the suspension-adapted Chinese Hamster Ovary (CHO) cell lines has become the method of choice for this task. The antibodies can be secreted into the media, which facilitates subsequent purification, and can be glycosylated. However, in general, protein production in CHO cells is expensive and may provide variable outcomes, namely in laboratories without previous experience. While achievable yields may be influenced by the nucleotide sequence, there are other aspects of the process which offer space for optimization, like gene delivery method, cultivation process or expression plasmid design. Polyethylenimine (PEI)-mediated gene delivery is frequently employed as a low-cost alternative to liposome-based methods. In this work, we are proposing a TGE platform for universal medium-scale production of antibodies and other proteins in CHO cells, with a novel expression vector allowing fast and flexible cloning of new genes and secretion of translated proteins. The production cost has been further reduced using recyclable labware. Nine days after transfection, we routinely obtain milligrams of antibody Fabs or human lactoferrin in a 25 mL culture volume. Potential of the platform is established based on the production and crystallization of antibody Fabs and their complexes. Full article

Mutations in the COL7A1 gene lead to malfunction, reduction or complete absence of type VII collagen (C7) in the skin’s basement membrane zone (BMZ), impairing skin integrity. In epidermolysis bullosa (EB), more than 800 mutations in COL7A1 have been reported, leading to the dystrophic form of EB (DEB), a severe and rare skin blistering disease associated with a high risk of developing an aggressive form of squamous cell carcinoma. Here, we leveraged a previously described 3′-RTMS6m repair molecule to develop a non-viral, non-invasive and efficient RNA therapy to correct mutations within COL7A1 via spliceosome-mediated RNA trans-splicing (SMaRT). RTM-S6m, cloned into a non-viral minicircle-GFP vector, is capable of correcting all mutations occurring between exon 65 and exon 118 of COL7A1 via SMaRT. Transfection of the RTM into recessive dystrophic EB (RDEB) keratinocytes resulted in a trans-splicing efficiency of ~1.5% in keratinocytes and ~0.6% in fibroblasts, as confirmed on mRNA level via next-generation sequencing (NGS). Full-length C7 protein expression was primarily confirmed in vitro via immunofluorescence (IF) staining and Western blot analysis of transfected cells. Additionally, we complexed 3′-RTMS6m with a DDC642 liposomal carrier to deliver the RTM topically onto RDEB skin equivalents and were subsequently able to detect an accumulation of restored C7 within the basement membrane zone (BMZ). In summary, we transiently corrected COL7A1 mutations in vitro in RDEB keratinocytes and skin equivalents derived from RDEB keratinocytes and fibroblasts using a non-viral 3′-RTMS6m repair molecule. Full article

Tumor metastasis is a major concern in cancer therapy. In this context, focal adhesion kinase (FAK) gene overexpression, which mediates cancer cell migration and invasion, has been reported in several human tumors and is considered a potential therapeutic target. However, gene-based treatment has certain limitations, including a lack of stability and low transfection ability. In this study, a biocompatible lipopolyplex was synthesized to overcome the aforementioned limitations. First, polyplexes were prepared using poly(2-Hydroxypropyl methacrylamide-co-methylacrylate-hydrazone-pyridoxal) (P(HPMA-co-MA-hyd-VB6)) copolymers, which bore positive charges at low pH value owing to protonation of pyridoxal groups and facilitated electrostatic interactions with negatively charged FAK siRNA. These polyplexes were then encapsulated into methoxy polyethylene glycol (mPEG)-modified liposomes to form lipopolyplexes. Doxorubicin (DOX) was also loaded into lipopolyplexes for combination therapy with siRNA. Experimental results revealed that lipopolyplexes successfully released DOX at low pH to kill cancer cells and induced siRNA out of endosomes to inhibit the translation of FAK proteins. Furthermore, the efficient accumulation of lipopolyplexes in the tumors led to excellent cancer therapeutic efficacy. Overall, the synthesized lipopolyplex is a suitable nanocarrier for the co-delivery of chemotherapeutic agents and genes to treat cancers. Full article

The design of cationic liposomes for efficient mRNA delivery can significantly improve mRNA-based therapies. Lipoplexes based on polycationic lipid 1,26-bis(cholest-5-en-3β-yloxycarbonylamino)-7,11,16,20-tetraazahexacosane tetrahydrochloride (2X3) and helper lipid 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) were formulated in different molar ratios (1:1, 1:2, 1:3) to efficiently deliver model mRNAs to BHK-21 and A549. The objective of this study was to examine the effect of 2X3-DOPE composition as well as lipid-to-mRNA ratio (amino-to-phosphate group ratio, N/P) on mRNA transfection. We found that lipoplex-mediated transfection efficiency depends on both liposome composition and the N/P ratio. Lipoplexes with an N/P ratio of 10/1 showed nanometric hydrodynamic size, positive ζ potential, maximum loading, and transfection efficiency. Liposomes 2X3-DOPE (1:3) provided the superior delivery of both mRNA coding firefly luciferase and mRNA-eGFP into BHK-21 cells and A549 cells, compared with commercial Lipofectamine MessengerMax. Full article

The goal of this study was to establish a procedure for gene delivery mediated by cationic liposomes in quiescent differentiated HepaRG™ human hepatoma cells. We first identified several cationic lipids promoting efficient gene transfer with low toxicity in actively dividing HepG2, HuH7, BC2 and progenitor HepaRG™ human hepatoma cells. The lipophosphoramidate Syn1-based nanovector, which allowed the highest transfection efficiencies of progenitor HepaRG™ cells, was next used to transfect differentiated HepaRG™ cells. Lipofection of these cells using Syn1-based liposome was poorly efficient most likely because the differentiated HepaRG™ cells are highly quiescent. Thus, we engineered the differentiated HepaRG™ Mitogenic medium supplement (ADD1001) that triggered robust proliferation of differentiated cells. Importantly, we characterized the phenotypical changes occurring during proliferation of differentiated HepaRG™ cells and demonstrated that mitogenic stimulation induced a partial and transient decrease in the expression levels of some liver specific functions followed by a fast recovery of the full differentiation status upon removal of the mitogens. Taking advantage of the proliferation of HepaRG™ cells, we defined lipofection conditions using Syn1-based liposomes allowing transient expression of the cytochrome P450 2D6, a phase I enzyme poorly expressed in HepaRG cells, which opens new means for drug metabolism studies in HepaRG™ cells. Full article

Since Jon A. Wolff found skeletal muscle cells being able to express foreign genes and Russell J. Mumper increased the gene transfection efficiency into the myocytes by adding polymers, skeletal muscles have become a potential gene delivery and expression target. Different methods have been developing to deliver transgene into skeletal muscles. Among them, viral vectors may achieve potent gene delivery efficiency. However, the potential for triggering biosafety risks limited their clinical applications. Therefore, non-viral biomaterial-mediated methods with reliable biocompatibility are promising tools for intramuscular gene delivery in situ. In recent years, a series of advanced non-viral gene delivery materials and related methods have been reported, such as polymers, liposomes, cell penetrating peptides, as well as physical delivery methods. In this review, we summarized the research progresses and challenges in non-viral intramuscular gene delivery materials and related methods, focusing on the achievements and future directions of polymers. Full article

The generation of reactive oxygen species (ROS) can affect cationic liposome-mediated transfection. In this study, we focused on a specific class of antioxidants, flavonoids, to investigate the transfection efficiency using cationic liposome/plasmid DNA complexes (lipoplexes) in 2D and 3D cultures of Colon26 and HepG2 cells, respectively. All tested flavonoids enhanced the transfection efficiency in 2D Colon26 and HepG2 cells. Among the tested flavonoids, 25 µM quercetin showed the highest promotion effect of 8.4- and 7.6-folds in 2D Colon26 and HepG2 cells, respectively. Transfection was also performed in 3D cultures of Colon26 and HepG2 cells using lipoplexes with quercetin. Quercetin (12.5 µM) showed the highest transfection efficiency at all transfection timings in 3D Colon26 and HepG2 cells with increased cell viability. Flow cytometry revealed that quercetin treatment reduced the population of gene expression-negative cells with high ROS levels and increased the number of gene expression-positive cells with low ROS levels in HepG2 cells. Information from this study can be valuable to develop strategies to promote transfection efficiency and attenuate cytotoxicity using lipoplexes. Full article

Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated nuclease 9 (Cas9) gene-editing offers exciting new therapeutic possibilities for disease treatment with a genetic etiology such as cancer, cardiovascular, neuronal, and immune disorders. However, its clinical translation is being hampered by the lack of safe, versatile, and effective nonviral delivery systems. Herein we report on the preparation and application of two cationic liposome–DNA systems (i.e., lipoplexes) for CRISPR/Cas9 gene delivery. For that purpose, two types of cationic lipids are used (DOTAP, monovalent, and MVL5, multivalent with +5e nominal charge), along with three types of helper lipids (DOPC, DOPE, and monoolein (GMO)). We demonstrated that plasmids encoding Cas9 and single-guide RNA (sgRNA), which are typically hard to transfect due to their large size (>9 kb), can be successfully transfected into HEK 293T cells via MVL5-based lipoplexes. In contrast, DOTAP-based lipoplexes resulted in very low transfection rates. MVL5-based lipoplexes presented the ability to escape from lysosomes, which may explain the superior transfection efficiency. Regarding gene editing, MVL5-based lipoplexes achieved promising GFP knockout levels, reaching rates of knockout superior to 35% for charge ratios (+/−) of 10. Despite the knockout efficiency being comparable to that of Lipofectamine 3000^® commercial reagent, the non-specific gene knockout is more pronounced in MVL5-based formulations, probably resulting from the considerable cytotoxicity of these formulations. Altogether, these results show that multivalent lipid-based lipoplexes are promising CRISPR/Cas9 plasmid delivery vehicles, which by further optimization and functionalization may become suitable in vivo delivery systems. Full article