bims-novged Biomed News
on Non-viral vectors for gene delivery
Issue of 2021‒07‒11
eight papers selected by
Benjamin Winkeljann
Ludwig-Maximilians University

  1. Int J Nanomedicine. 2021 ;16 4451-4470
      Background: Liver fibrosis is a chronic liver disease with excessive production of extracellular matrix proteins, leading to cirrhosis, hepatocellular carcinoma, and death.Purpose: This study aimed at the development of a novel derivative of polyethyleneimine (PEI) that can effectively deliver transforming growth factor β (TGFβ) siRNA and inhibit chemokine receptor 4 (CXCR4) for TGFβ silencing and CXCR4 Inhibition, respectively, to treat CCl4-induced liver fibrosis in a mouse model.
    Methods: Cyclam-modified PEI (PEI-Cyclam) was synthesized by incorporating cyclam moiety into PEI by nucleophilic substitution reaction. Gel electrophoresis confirmed the PEI-Cyclam polyplex formation and stability against RNAase and serum degradation. Transmission electron microscopy and zeta sizer were employed for the morphology, particle size, and zeta potential, respectively. The gene silencing and CXCR4 targeting abilities of PEI-Cyclam polyplex were evaluated by luciferase and CXCR4 redistribution assays, respectively. The histological and immunohistochemical staining determined the anti-fibrotic activity of PEI-Cyclam polyplex. The TGFβ silencing of PEI-Cyclam polyplex was authenticated by Western blotting.
    Results: The 1H NMR of PEI-Cyclam exhibited successful incorporation of cyclam content onto PEI. The PEI-Cyclam polyplex displayed spherical morphology, positive surface charge, and stability against RNAse and serum degradation. Cyclam modification decreased the cytotoxicity and demonstrated CXCR4 antagonistic and luciferase gene silencing efficiency. PEI-Cyclam/siTGFβ polyplexes decreased inflammation, collagen deposition, apoptosis, and cell proliferation, thus ameliorating liver fibrosis. Also, PEI-Cyclam/siTGFβ polyplex significantly downregulated α-smooth muscle actin, TGFβ, and collagen type III.
    Conclusion: Our findings validate the feasibility of using PEI-Cyclam as a siRNA delivery vector for simultaneous TGFβ siRNA delivery and CXCR4 inhibition for the combined anti-fibrotic effects in a setting of CCl4-induced liver fibrosis.
    Keywords:  CXCR4; cyclam; gene delivery; liver fibrosis; polyethyleneimine
  2. Nanoscale. 2021 Jul 07.
      MicroRNAs (miRNAs) are emerging as a novel class of molecular targets and therapeutics to control gene expression for tissue repair and regeneration. However, a safe and effective transfection of miRNAs to cells has been a major barrier to their applications. In this work, a multifunctional polyplex micelle named PPP-RGI was developed as a non-viral gene vector for the efficient transfection of miR-218 (an osteogenic miRNA regulator) to bone marrow-derived mesenchymal stem cells (BMSCs) for accelerated osteogenic differentiation. PPP-RGI was designed and synthesized via conjugation of a multifunctional R9-G4-IKVAVW (RGI) peptide onto an amphiphilic poly(lactide-co-glycolide)-g-polyethylenimine-b-polyethylene glycol (PPP) copolymer. PPP-RGI self-assembled into polyplex micelles and strongly condensed miR-218 to prevent its RNase degradation. When the PPP-RGI/miR-218 complex was brought into contact with BMSCs, it exhibited high internalization efficiency and a fast escape from endo/lysosomes of the BMSCs. Subsequently, miR-218 released from the PPP-RGI/miR-218 complex regulated gene expressions and significantly enhanced the osteogenic differentiation of BMSCs. The multifunctional peptide conjugated nanocarrier serves as an effective miRNA delivery vector to promote osteogenesis.
  3. Adv Healthc Mater. 2021 Jul 03. e2100938
      Stimuli-responsive nanosystems have been widely applied as effective modalities for drug/gene co-delivery in cancer treatment. However, precise spatiotemporal manipulations of drug/gene co-delivery, as well as multi-modality imaging-guided cancer therapy, still remain a daunting challenge. Here, multifunctional polyprodrug/siRNA loaded upconversion nanoparticles (UCNPs) are reported that combine computed tomography (CT), magnetic resonance (MR), and upconversion luminescence (UCL) tri-modality imaging and near-infrared (NIR) light-activated drug/gene on-demand delivery. The photoactivatable platinum(IV) (Pt(IV))-backbone polymers (PPt) and the siRNA targeting polo-like kinase 1 (Plk1) are loaded on the surface of polyethyleneimine (PEI)-coated UCNPs (PUCNP) to obtain the multifunctional polyprodrug/siRNA loaded UCNPs (PUCNP@Pt@siPlk1). The PUCNP@Pt@siPlk1 can be served as a "nanotransducer" to convert NIR light (980 nm) into local ultraviolet (UV) to visible light for the cleavage of photosensitive PPt, resulting in the simultaneous on-demand release of high toxic platinum(II) (Pt(II)) and siPlk1. Meanwhile, the PUCNP@Pt@siPlk1 has CT, T1 -weighted MR, and UCL tri-modality imaging abilities. Based on these merits, PUCNP@Pt@siPlk1 displayed excellent synergistic therapeutic efficacy via image-guided and NIR light-activated platinum-based chemotherapy and RNA interfering in vitro and in vivo. Thus, this developed nanosystem with NIR light-controlled drug/gene delivery and multi-modality imaging abilities, will display great potential in combining chemotherapy and gene therapy.
    Keywords:  combination therapy; drug delivery; multi-modality imaging; near-infrared; upconversion nanoparticles
  4. Mol Pharm. 2021 Jul 06.
      Celiac disease is a chronic inflammatory condition characterized by activation of the immune system in response to deamidation of gluten peptides brought about by tissue transglutaminase-2 (TG2). Overexpression of interleukin-15 (IL-15) in the intestinal epithelium and the lamina propria leads to the dysregulation of the immune system, leading to epithelial damage. The goal of this study was to develop an RNA interference therapeutic strategy for celiac disease using a combination of TG2 and IL-15 gene silencing in the inflamed intestine. TG2 and IL-15 silencing siRNA sequences, along with scrambled control, were encapsulated in a nanoparticle-in-microsphere oral system (NiMOS) and administered in a poly(I:C) mouse model of celiac disease. Single TG2 and IL-15 siRNA therapy and the combination showed effective gene silencing in vivo. Additionally, it was found that IL-15 gene silencing alone and combination in the NiMOS significantly reduced other proinflammatory cytokines. The tissue histopathology data also confirmed a reduction in immune cell infiltration and restoration of the mucosal architecture and barrier function in the intestine upon treatment. Overall, the results of this study show evidence that celiac disease can be potentially treated with an oral microsphere formulation using a combination of TG2 and IL-15 RNA interference therapeutic strategies.
    Keywords:  celiac disease; interleukin-15 (IL-15); nanoparticle-in-microsphere oral system (NiMOS); oral gene silencing; poly(I:C) mouse model; transglutaminase-2 (TG2)
  5. Colloids Surf B Biointerfaces. 2021 Jun 29. pii: S0927-7765(21)00399-4. [Epub ahead of print]206 111955
      Combination therapy based on the co-delivery of therapeutic genes and anti-cancer drugs has emerged as a promising approach in the cancer treatment, and stimuli-responsive delivery systems could further improve the therapeutic efficacy. Herein, an ATP aptamer and its complementary DNA were used to form Duplex into which doxorubicin (DOX) was loaded to construct DOX-Duplex, and then the lipoic acid-modified oligoethyleneimine (LA-OEI) was employed as a carrier to realize the co-delivery of DOX-Duplex and miR-23b. The ternary nanocomplex LA-OEI/miR-23b/DOX-Duplex showed excellent anti-proliferative effect by inducing the cell apoptosis via mitochondrial signaling pathway and arresting the cell cycle at S phase. Meanwhile, the co-delivery of DOX-Duplex and miR-23b could efficiently inhibit the metastasis of cancer cells by reducing the expression level of MMP-9. The favorable anti-tumor efficacy of ternary nanocomplex was attributed to the rapid drug release in response to intracellular ATP concentration and reduction conditions and the synergistic effect between DOX-Duplex and miR-23b. Thus, ATP aptamer and reduction-responsive polymer provided a convenient platform to construct dual stimuli-responsive systems for the co-delivery of gene and drug in the cancer treatment.
    Keywords:  ATP response; Aptamer; Chemotherapy; Gene therapy; Reduction response
  6. ACS Cent Sci. 2021 Jun 23. 7(6): 990-1000
      We synthesized a series of poly(disulfide)s by ring-opening polymerization and demonstrated that the copolymerization of monomer 1 containing diethylenetriamine moieties and monomer 2 containing guanidyl ligands could generate an efficient delivery platform for different forms of CRISPR-Cas9-based genome editors, including plasmid, mRNA, and protein. The excellent delivery performance of designed poly(disulfide)s stems from their delicate molecular structures to interact with genome-editing biomacromolecules, unique delivery pathways to mediate the cellular uptake of CRISPR-Cas9 cargoes, and strong ability to escape the endosome. The degradation of poly(disulfide)s by intracellular glutathione not only promotes the timely release of CRISPR-Cas9 machineries into the cytosol but also minimizes the cytotoxicity that nondegradable polymeric carriers often encounter. These merits collectively account for the excellent ability of poly(disulfide)s to mediate different forms of CRISPR-Cas9 for their efficient genome-editing activities in vitro and in vivo.
  7. Int J Pharm. 2021 Jun 30. pii: S0378-5173(21)00647-5. [Epub ahead of print] 120842
      MicroRNAs (miRNA) is vital for gene expression regulation and normal kidney function. Mainly, miRNA-30a is responsible for the homeostasis of podocytes. In the diabetic nephropathic condition, miRNA-30a is directly and primarily suppressed by hyperglycemic kidney induced Notch signaling pathway leads to podocyte damage and apoptosis. Thus, transferring the exogenous miRNA-30a to podocytes might improve albuminuria as well as podocytes injury. The deprived stability, poor targetability, and low specificity in vivo are critical limitations to attain this objective. This investigation reports the specific and efficient delivery of miRNA-30a mimic via cyclo(RGDfC)-gated polymeric-nanoplexes with dendrimer templates to alleviate podocyte conditions. The nanoplexes able to protect RNase enzyme and to exhibit greater cellular uptake viaαvβ3 receptor selective binding in HG treated podocytes. The nanoplexes up-regulated the expression level of miRNA-30a and repress the elevated Notch-1 signaling in HG exposed podocytes. The critical results of in vivo experimentation attribute marked suppression of Notch-1 in streptozotocin (STZ) induced diabetic C57BL/6 mice and reduced glomerular expansion and fibrosis in the glomerular area. Developed nanoplexes represents an efficient platform for the targeted delivery of exogenous miRNA to podocytes. The approach developed herein could be extrapolated to other gene therapeutics and other kidney-related diseases.
    Keywords:  Diabetic model; Gene therapy; Nanoplexes; Podocyte targeting; microRNAs delivery
  8. Adv Sci (Weinh). 2021 Jul 08. e2100629
      MicroRNAs are potential candidates for lung cancer prevention and therapy. A major limitation is the lack of an efficient delivery system to directly deliver miRNA to cancer cells while limiting systemic exposure. The delivery of miRNA via inhalation is a potential strategy for lung cancer prevention in high-risk individuals. In this study, the authors investigate the efficacy of aerosolized let-7b miRNA treatment in lung cancer prevention. Let-7b shows significant inhibition of B[a]P-induced lung adenoma with no detectable side effects. Single-cell RNA sequencing of tumor-infiltrating T cells from primary tumors reveals that Let-7b post-transcriptionally suppresses PD-L1 and PD-1 expression in the tumor microenvironment, suggesting that let-7b miRNAs may promote antitumor immunity in vivo. Let-7b treatment decreases the expression of PD-1 in CD8+ T cells and reduces PD-L1 expression in lung tumor cells. The results suggest that this aerosolized let-7b mimic is a promising approach for lung cancer prevention, and that the in vivo tumor inhibitory effects of let-7b are mediated, at least in part, by immune-promoting effects via downregulating PD-L1 in tumors and/or PD-1 on CD8+ T cells. These changes potentiate antitumor CD8+ T cell immune responses, and ultimately lead to tumor inhibition.
    Keywords:  immunity; let-7b; lung cancer; miRNA; pulmonary aerosol delivery; single-cell RNA sequencing