bims-novged Biomed News
on Non-viral vectors for gene delivery
Issue of 2022‒10‒23
ten papers selected by
the Merkel lab
Ludwig-Maximilians University

  1. ACS Nano. 2022 Oct 21.
      Ionizable cationic lipid-containing lipid nanoparticles (LNPs) are the most clinically advanced non-viral gene delivery platforms, holding great potential for gene therapeutics. This is exemplified by the two COVID-19 vaccines employing mRNA-LNP technology from Pfizer/BioNTech and Moderna. Herein, we develop a chemical library of ionizable cationic lipids through a one-step chemical-biological enzyme-catalyzed esterification method, and the synthesized ionizable lipids were further prepared to be LNPs for mRNA delivery. Through orthogonal design of experiment methodology screening, the top-performing AA3-DLin LNPs show outstanding mRNA delivery efficacy and long-term storage capability. Furthermore, the AA3-DLin LNP COVID-19 vaccines encapsulating SARS-CoV-2 spike mRNAs successfully induced strong immunogenicity in a BALB/c mouse model demonstrated by the antibody titers, virus challenge, and T cell immune response studies. The developed AA3-DLin LNPs are an excellent mRNA delivery platform, and this study provides an overall perspective of the ionizable cationic lipids, from aspects of lipid design, synthesis, screening, optimization, fabrication, characterization, and application.
    Keywords:  COVID-19 vaccines; gene delivery; ionizable lipids; lipid nanoparticle; mRNA therapeutics
  2. J Control Release. 2022 Oct 17. pii: S0168-3659(22)00690-3. [Epub ahead of print]
      With specific and inherent mRNA cleaving activity, small interfering RNA (siRNA) has been deemed promising therapeutics to reduce the exacerbation rate of asthma by inhibiting the expression and release of proinflammatory cytokines from airway epithelial cells (AECs). To exert the therapeutic effects of siRNA drugs, nano-formulations with high efficiency and safety are required to deliver these nucleic acids to the target cells. Herein, we exploited novel inhaled lipid nanoparticles (LNPs) targeting intercellular adhesion molecule-1 (ICAM-1) receptors on the apical side of AECs. This delivery system is meant to enhance the specific delivery efficiency of siRNA in AECs to prevent the expression of proinflammatory cytokines in AECs and the concomitant symptoms in parallel. A cyclic peptide that resembles part of the capsid protein of rhinovirus and binds to ICAM-1 receptors was initially conjugated with cholesterol and subsequently assembled with ionizable cationic lipids to form the LNPs (Pep-LNPs) loaded with siRNA against thymic stromal lymphopoietin (TSLP siRNA). The obtained Pep-LNPs were subjected to thorough characterization and evaluations in vitro and in vivo. Pep-LNPs significantly enhanced cellular uptake and gene silencing efficiency in human epithelial cells expressing ICAM-1 in vitro, exhibited AEC-specific delivery and improved the gene silencing effect in ovalbumin-challenged asthmatic mice after pulmonary administration. More importantly, Pep-LNPs remarkably downregulated the expression of TSLP in AECs, effectively alleviated inflammatory cell infiltration, and reduced the secretion of other proinflammatory cytokines, including IL-4 and IL-13, as well as mucus production in asthmatic mice. This study demonstrates that Pep-LNPs are safe and efficient to deliver siRNA drugs to asthmatic AECs and could potentially alleviate allergic asthma by inhibiting the overexpression of proinflammatory cytokines in the airway.
    Keywords:  Airway epithelial cells; Asthma; Lipid nanoparticles; Pulmonary delivery; siRNA
  3. Sci Rep. 2022 Oct 20. 12(1): 17520
      SiRNA is a new generation of drug molecules and a new approach for treating a variety of diseases such as cancer and viral infections. SiRNA delivery to cells and translocation into cytoplasm are the main challenges in the clinical application of siRNA. Lipid carriers are one of the most successful carriers for siRNA delivery. In this study, we investigated the interaction of siRNA with a zwitterionic bilayer and how ion concentration and lipid conjugation can affect it. The divalent cation such as Mg2+ ions could promote the siRNA adsorption on the bilayer surface. The cation ions can bind to the head groups of lipids and the grooves of siRNA molecules and form bridges between the siRNA and bilayer surface. Our findings demonstrated the bridges formed by divalent ions could facilitate the attachment of siRNA to the membrane surface. We showed that the divalent cations can regulate the bridging-driven membrane attachment and it seems the result of this modulation can be used for designing biomimetic devices. In the following, we examined the effect of cations on the interaction between siRNA modified by cholesterol and the membrane surface. Our MD simulations showed that in the presence of Mg2+, the electrostatic and vdW energy between the membrane and siRNA were higher compared to those in the presence of NA+. We showed that the electrostatic interaction between membrane and siRNA cannot be facilitated only by cholesterol conjugated. Indeed, cations are essential to create coulomb repulsion and enable membrane attachment. This study provides important insight into liposome carriers for siRNA delivery and could help us in the development of siRNA-based therapeutics. Due to the coronavirus pandemic outbreak, these results may shed light on the new approach for treating these diseases and their molecular details.
  4. J Am Chem Soc. 2022 Oct 19.
      Micelleplexes show great promise as effective polymeric delivery systems for nucleic acids. Although studies have shown that spherical micelleplexes can exhibit superior cellular transfection to polyplexes, to date there has been no report on the effects of micelleplex morphology on cellular transfection. In this work, we prepared precision, length-tunable poly(fluorenetrimethylenecarbonate)-b-poly(2-(dimethylamino)ethyl methacrylate) (PFTMC16-b-PDMAEMA131) nanofiber micelleplexes and compared their properties and transfection activity to those of the equivalent nanosphere micelleplexes and polyplexes. We studied the DNA complexation process in detail via a range of techniques including cryo-transmission electron microscopy, atomic force microscopy, dynamic light scattering, and ζ-potential measurements, thereby examining how nanofiber micelleplexes form, as well the key differences that exist compared to nanosphere micelleplexes and polyplexes in terms of DNA loading and colloidal stability. The effects of particle morphology and nanofiber length on the transfection and cell viability of U-87 MG glioblastoma cells with a luciferase plasmid were explored, revealing that short nanofiber micelleplexes (length < ca. 100 nm) were the most effective delivery vehicle examined, outperforming nanosphere micelleplexes, polyplexes, and longer nanofiber micelleplexes as well as the Lipofectamine 2000 control. This study highlights the potential importance of 1D micelleplex morphologies for achieving optimal transfection activity and provides a fundamental platform for the future development of more effective polymeric nucleic acid delivery vehicles.
  5. Naunyn Schmiedebergs Arch Pharmacol. 2022 Oct 18.
      Biocompatibility of nanoparticles is the most essential factor in their use in clinical applications. In this study, hyperbranched spermine (HS), hyperbranched spermine-polyethylene glycol-folic acid (HSPF), and hyperbranched spermine-polyethylene glycol-glucose (HSPG) were synthesized for DNA protection and gene delivery to breast cancer cells. The synthesis of HSPG and HSPF was confirmed using proton nuclear magnetic resonance (H-NMR), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) spectroscopy. The HS/DNA, HSPF/DNA, HSPG/DNA, and hyperbranched spermine-polyethylene glycol-folic acid/glucose/DNA (HSPFG/DNA) nanoparticles were prepared by combining different concentrations of HS, HSPF, and HSPG with the same amount of DNA. The ability of HS, HSPF, and HSPG to interact with DNA and protect it against plasm digestion was evaluated using agarose gel. Moreover, in vivo and in vitro biocompatibility of HSPF/DNA, HSPG/DNA, and HSPFG/DNA was investigated using MTT assay and calculating weight change and survival ratio of BALB/c mice, respectively. The results of agarose gel electrophoresis showed that HS, HSPF, and HSPG have the high ability to neutralize the negative charge of DNA and protect it against plasma degradation. The results of in vivo cytotoxicity assay revealed that the HSPF/DNA, HSPG/DNA, and HSPFG/DNA nanoparticles have good biocompatibility on female BALB/c mice. In vitro and in vivo transfection assays revealed that functionalization of the surface of HS using polyethylene glycol-folic acid (HSPF) and polyethylene glycol-glucose (HSPG) significantly increases gene delivery efficiency in vitro and in vivo. These results also showed that gene transfer using both HSPF and HSPG copolymers increases gene transfer efficiency compared to when only one of them is used. The HSPFG/DNA nanoparticles have a high potential for use in therapeutic applications because of their excellent biocompatibility and high gene transfer efficiency to breast cancer tissue.
    Keywords:  Biocompatibility; Folic acid; Gene delivery; Glucose; Hyperbranched spermine
  6. Nanoscale Horiz. 2022 Oct 19.
      The liver is a vital organ that functions to detoxify the body. Liver cancer and infectious diseases such as influenza and malaria can fatally compromise liver function. mRNA delivery is a relatively new means of therapeutic treatment which enables expression of tumor or pathogenic antigens, and elicits immune responses for therapeutic or prophylactic effect. Novel nanoparticles with unique biological properties serving as mRNA carriers have allowed mRNA-based therapeutics to become more clinically viable and relevant. In this review, we highlight recent progress in development of nanoparticle-based mRNA delivery systems for treatment of various liver diseases. First, we present developments in nanoparticle systems used to deliver mRNAs, with specific focus on enhanced cellular uptake and endosomal escape achieved through the use of these nanoparticles. To provide context for diseases that target the liver, we provide an overview of the function and structure of the liver, as well as the role of the immune system in the liver. Then, mRNA-based therapeutic approaches for addressing HCC are highlighted. We also discuss nanoparticle-based mRNA vaccines for treating hepatotropic infectious diseases. Finally, we present current challenges in the clinical translation of nanoparticle-based mRNA delivery systems and provide outlooks for their utilization in treating liver-related diseases.
  7. Drug Deliv Transl Res. 2022 Oct 16.
      Nanotechnology-based drug delivery platforms have shown great potential in overcoming the limitations of conventional therapy for glioblastoma (GBM). However, permeation across the blood-brain barrier (BBB), physiological complexity of the brain, and glioma targeting strategies cannot entirely meet the challenging requirements of distinctive therapeutic delivery stages. The objective of this research is to fabricate lipid nanoparticles (LNPs) for the co-delivery of paclitaxel (PTX) and miltefosine (HePc) a proapoptotic agent decorated with transferrin (Tf-PTX-LNPs) and investigate its anti-glioma activity both in vitro and in vivo orthotopic NOD/SCID GBM mouse model. The present study demonstrates the anti-glioma effect of the dual drug combination of PTX and proapoptotic HePc lipid-based transferrin receptor (TfR) targeted alternative delivery (direct nose to brain transportation) of the nanoparticulate system (Tf-PTX-LNPs, 364 ± 5 nm, -43 ± 9 mV) to overcome the O6-methylguanine-DNA methyltransferase induce drug-resistant for improving the effectiveness of GBM therapy. The resulting nasally targeted LNPs present good biocompatibility, stability, high BBB transcytosis through selective TfR-mediated uptake by tumor cells, and effective tumor penetration in the brain of GBM induced mice. We observed markedly enhanced anti-proliferative efficacy of the targeted LNPs in U87MG cells compared to free drug. Nasal targeted LNPs had shown significantly improved brain concentration (Cmax fivefold and AUC0-24 4.9 fold) with early tmax (0.5 h) than the free drug. In vivo intracranial GBM-bearing targeted LNPs treated mice exhibited significantly prolonged survival with improved anti-tumor efficacy accompanied by reduced toxicity compared to systemic Taxol® and nasal free drug. These findings indicate that the nasal delivery of targeted synergistic nanocarrier holds great promise as a non-invasive adjuvant chemotherapy therapy of GBM.
    Keywords:  Blood–brain-barrier; Glioblastoma; Intracranial; Nanoparticles; Nasal delivery; Paclitaxel; Proapoptotic miltefosine
  8. Phys Rev E. 2022 Sep;106(3-1): 034408
      Successful intracellular delivery of nucleic acids (NAs) hinges on many factors, one of them being NAs' efficacious escape from endosomes. As competent NA vectors, pH-responsive gemini surfactants (GSs) might achieve high efficacy by facilitating endosomal escape. However, how the GSs assist the escape remains debated as many proposed mechanisms still lack experimental support, which hinders replication and further improvement of the efficient delivery. Here, via UV, fluorescence spectroscopy, and small-angle neutron scattering (SANS), we examined a pH-responsive GS's and a pH-unresponsive GS's capabilities to compact DNA and withstand binding competition, and their interactions with model endosomal and lysosomal membranes, at varied pHs. Acidification-driven enhancement of DNA-compaction capability and of stability against binding competition were found specific to the pH-responsive GS. Alongside the pH-responsive GS's structural perturbation to the membranes as observed with SANS, the features suggest that pH-responsive GSs facilitate endosomal escape by releasing excess GS molecules from DNA-GS complexes upon acidification in endosome maturation, with the released GS molecules disrupting endosomal and lysosomal membranes and thereby assisting the escape. A general design principle for NA vectors is proposed on the basis of this experimental finding.
  9. Int Immunopharmacol. 2022 Oct 14. pii: S1567-5769(22)00738-X. [Epub ahead of print]113(Pt A): 109254
      mRNA vaccination is considered to be a promising strategy for tumor immunotherapy. Among, adequate antigen expression and regulation of tumor immune microenvironment are still the key to achieving therapeutic immounotherapy. In oreder to protect mRNA delivered to cells and reverse damaged dendritic cells(DCs), a novel vaccine delivery system composed of an α-Galactose ceramide/cationic liposome complex(α-GC-Lip) was constructed. The α-GC-liposome/protamine/mRNA vaccine complexes(α-GC-LPR) enabled the mRNA to be successfully translated into protein in the cytoplasm of antigen-presenting cells. Further, α-GC-LPR could stimulate dendritic cell maturation via significantly increasing the expression of bone marrow-derived cells(BMDCs) surface molecules and secretion of cytokines to improve the efficacy of immunotherapy. In vivo study, the α-GC-LPR was combined with programmed cell death protein 1(PD-1) inhibitor could activate natural killer cell(NK), T cells as well as significantly reduce the immunosuppression of immune cells, which induced strong antigen-specific immunity in breast cancer model. Our study indicated that the α-GC-LPR combined with immune checkpoint inhibitors as a potential design strategy to effectively enhance the antitumor immune response.
    Keywords:  HER2 positive breast cancer; PD-1 inhibitor; Tumor immune microenvironment; mRNA vaccine; α-GC
  10. Expert Opin Drug Deliv. 2022 Oct 17. 1-22
      INTRODUCTION: Human serum albumin is the most abundant transport protein in plasma, which has recently been extensively utilized to form nanoparticles for drug delivery in cancer. The primary reason for selecting albumin protein as drug delivery cargo is its excellent biocompatibility, biodegradability, and non-immunogenicity. Moreover, the albumin structure containing three homologous domains constituted of a single polypeptide (585 amino acid) incorporates various hydrophobic drugs by non-covalent interactions. Albumin shows active tumor targeting via their interaction with gp60 and SPARC proteins abundant in the tumor-associated endothelial cells and the tumor microenvironment.AREAS COVERED: The review discusses the importance of albumin as a drug-carrier system, general procedures to prepare albumin NPs, and the current trends in using albumin-based nanomedicines to deliver various chemotherapeutic agents. The various applications of albumin in the nanomedicines, such as NPs surface modifier and fabrication of hybrid/active-tumor targeted NPs, are delineated based on current trends.
    EXPERT OPINION: Nanomedicines have the potential to revolutionize cancer treatment. However, clinical translation is limited majorly due to the lack of suitable nanomaterials offering systemic stability, optimum drug encapsulation, tumor-targeted delivery, sustained drug release, and biocompatibility. The potential of albumin could be explored in nanomedicines fabrication for superior treatment outcomes in cancer.
    Keywords:  Albumin; anticancer drug; cancer; chemotherapeutic agents; conjugation; loading; nanoparticles; targeting