Multi-Component Delivery Systems for Targeted Delivery of Nucleic Acids

A special issue of Pharmaceuticals (ISSN 1424-8247). This special issue belongs to the section "Pharmaceutical Technology".

Deadline for manuscript submissions: closed (18 June 2021) | Viewed by 56109

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Guest Editor
Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Harry and Diane Rinker Health Science Campus, Irvine, CA 92618, USA
Interests: pharmaceutics; targeted delivery; RNA interference; cancer biology; signaling pathways
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Special Issue Information

Dear Colleagues,

Approaches to RNA interference have made a significant impact on research strategies and methodologies since the turn of the century. These approaches include but are not limited to plasmid DNA, small interfering RNA (siRNA), short hairpin RNA (shRNA), micro RNA (miRNA), oligonucleotides, and most recently, clustered regularly interspaced short palindromic repeats (CRISPR). Each approach offers certain advantages, and of course, has its own flaws. These approaches have provided reliable tools in basic and translational research, with the ability to target virtually any protein in a variety of mammalian cells and “silence” the expression of the target for a short period of time or permanently. However, despite promising initial results, this significant impact has not been translated into the wide clinical applications for which we all have hoped. Nucleic acid delivery is difficult, and has proven to be even more challenging in vivo. We have not given up yet. We are still exploring new approaches and novel carriers on a regular basis. This Special Issue aims to include review and research papers that provide a comprehensive look at the most recent attempts in nucleic acid delivery, focusing on multi-component delivery systems designed as safe and effective carriers. It is also hoped to shine light on the future directions for nucleic acid delivery.

Dr. Hamidreza Montazeri Aliabadi
Guest Editor

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Keywords

  • targeted delivery
  • multicomponent
  • RNA interference
  • in vitro
  • in vivo
  • shRNA
  • miRNA
  • oligonucleotides
  • CRISPR
  • plasmid

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Published Papers (11 papers)

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Research

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16 pages, 3625 KiB  
Article
Cyclic Peptide-Gadolinium Nanocomplexes as siRNA Delivery Tools
by Amir Nasrolahi Shirazi, Muhammad Imran Sajid, Dindyal Mandal, David Stickley, Stephanie Nagasawa, Joshua Long, Sandeep Lohan, Keykavous Parang and Rakesh Kumar Tiwari
Pharmaceuticals 2021, 14(11), 1064; https://0-doi-org.brum.beds.ac.uk/10.3390/ph14111064 - 20 Oct 2021
Cited by 2 | Viewed by 3077
Abstract
We have recently reported that a cyclic peptide containing five tryptophan, five arginine, and one cysteine amino acids [(WR)5C], was able to produce peptide-capped gadolinium nanoparticles, [(WR)5C]-GdNPs, in the range of 240 to 260 nm upon mixing with an [...] Read more.
We have recently reported that a cyclic peptide containing five tryptophan, five arginine, and one cysteine amino acids [(WR)5C], was able to produce peptide-capped gadolinium nanoparticles, [(WR)5C]-GdNPs, in the range of 240 to 260 nm upon mixing with an aqueous solution of GdCl3. Herein, we report [(WR)5C]-GdNPs as an efficient siRNA delivery system. The peptide-based gadolinium nanoparticles (50 µM) did not exhibit significant cytotoxicity (~93% cell viability at 50 µM) in human leukemia T lymphoblast cells (CCRF-CEM) and triple-negative breast cancer cells (MDA-MB-231) after 48 h. Fluorescence-activated cell sorting (FACS) analysis indicated that the cellular uptakes of Alexa-488-labeled siRNA were found to be enhanced by more than 10 folds in the presence of [(WR)5C]-GdNPs compared with siRNA alone in CCRF-CEM and MDA-MB-231 cells after 6 h of incubation at 37 °C. The gene silencing efficacy of the nanoparticles was determined via the western blot technique using an over-expressed gene, STAT-3 protein, in MDA-MB-231 cells. The results showed ~62% reduction of STAT-3 was observed in MDA-MB-231 with [(WR)5C]-GdNPs at N/P 40. The integrity of the cellular membrane of CCRF-CEM cells was found to be intact when incubated with [(WR)5C]-Gd nanoparticles (50 µM) for 2 h. Confocal microscopy reveals higher internalization of siRNA in MDA-MB-231 cells using [(WR)5C]-GdNPs at N/P 40. These results provided insight about the use of the [(WR)5C]-GdNPs complex as a potent intracellular siRNA transporter that could be a nontoxic choice to be used as a transfection agent for nucleic-acid-based therapeutics. Full article
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24 pages, 5783 KiB  
Article
Two Antibody-Guided Lactic-co-Glycolic Acid-Polyethylenimine (LGA-PEI) Nanoparticle Delivery Systems for Therapeutic Nucleic Acids
by Jian-Ming Lü, Zhengdong Liang, Dongliang Liu, Bin Zhan, Qizhi Yao and Changyi Chen
Pharmaceuticals 2021, 14(9), 841; https://0-doi-org.brum.beds.ac.uk/10.3390/ph14090841 - 25 Aug 2021
Cited by 6 | Viewed by 3495
Abstract
We previously reported a new polymer, lactic-co-glycolic acid-polyethylenimine (LGA-PEI), as an improved nanoparticle (NP) delivery for therapeutic nucleic acids (TNAs). Here, we further developed two antibody (Ab)-conjugated LGA-PEI NP technologies for active-targeting delivery of TNAs. LGA-PEI was covalently conjugated with a single-chain variable [...] Read more.
We previously reported a new polymer, lactic-co-glycolic acid-polyethylenimine (LGA-PEI), as an improved nanoparticle (NP) delivery for therapeutic nucleic acids (TNAs). Here, we further developed two antibody (Ab)-conjugated LGA-PEI NP technologies for active-targeting delivery of TNAs. LGA-PEI was covalently conjugated with a single-chain variable fragment antibody (scFv) against mesothelin (MSLN), a biomarker for pancreatic cancer (PC), or a special Ab fragment crystallizable region-binding peptide (FcBP), which binds to any full Ab (IgG). TNAs used in the current study included tumor suppressor microRNA mimics (miR-198 and miR-520h) and non-coding RNA X-inactive specific transcript (XIST) fragments; green fluorescence protein gene (GFP plasmid DNA) was also used as an example of plasmid DNA. MSLN scFv-LGA-PEI NPs with TNAs significantly improved their binding and internalization in PC cells with high expression of MSLN in vitro and in vivo. Anti-epidermal growth factor receptor (EGFR) monoclonal Ab (Cetuximab) binding to FcBP-LGA-PEI showed active-targeting delivery of TNAs to EGFR-expressing PC cells. Full article
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21 pages, 5106 KiB  
Article
Internalisation and Biological Activity of Nucleic Acids Delivering Cell-Penetrating Peptide Nanoparticles Is Controlled by the Biomolecular Corona
by Annely Lorents, Maria Maloverjan, Kärt Padari and Margus Pooga
Pharmaceuticals 2021, 14(7), 667; https://0-doi-org.brum.beds.ac.uk/10.3390/ph14070667 - 12 Jul 2021
Cited by 5 | Viewed by 2492
Abstract
Nucleic acid molecules can be transferred into cells to alter gene expression and, thus, alleviate certain pathological conditions. Cell-penetrating peptides (CPPs) are vectors that can be used for transfecting nucleic acids as well as many other compounds. CPPs associate nucleic acids non-covalently, forming [...] Read more.
Nucleic acid molecules can be transferred into cells to alter gene expression and, thus, alleviate certain pathological conditions. Cell-penetrating peptides (CPPs) are vectors that can be used for transfecting nucleic acids as well as many other compounds. CPPs associate nucleic acids non-covalently, forming stable nanoparticles and providing efficient transfection of cells in vitro. However, in vivo, expected efficiency is achieved only in rare cases. One of the reasons for this discrepancy is the formation of protein corona around nanoparticles, once they are exposed to a biological environment, e.g., blood stream. In this study, we compared protein corona of CPP-nucleic acid nanoparticles formed in the presence of bovine, murine and human serum. We used Western blot and mass-spectrometry to identify the major constituents of protein corona forming around nanoparticles, showing that proteins involved in transport, haemostasis and complement system are its major components. We investigated physical features of nanoparticles and measured their biological efficiency in splice-correction assay. We showed that protein corona constituents might alter the fate of nanoparticles in vivo, e.g., by subjecting them to phagocytosis. We demonstrated that composition of protein corona of nanoparticles is species-specific that leads to dissimilar transfection efficiency and should be considered while developing delivery systems for nucleic acids. Full article
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17 pages, 3806 KiB  
Article
Delivery of Bioactive Gene Particles via Gelatin-Collagen-PEG-Based Electrospun Matrices
by Eleni K. Tsekoura, Teo Dick, Porntipa Pankongadisak, Daniel Graf, Yaman Boluk and Hasan Uludağ
Pharmaceuticals 2021, 14(7), 666; https://0-doi-org.brum.beds.ac.uk/10.3390/ph14070666 - 12 Jul 2021
Cited by 13 | Viewed by 3527
Abstract
The fabrication of fiber mats via electrospinning has been adopted in the last decades to produce high quality scaffolds for tissue engineering. However, an effective combination of electrospinning methods with gene delivery therapies remains a challenge. In this study, we describe how the [...] Read more.
The fabrication of fiber mats via electrospinning has been adopted in the last decades to produce high quality scaffolds for tissue engineering. However, an effective combination of electrospinning methods with gene delivery therapies remains a challenge. In this study, we describe how the delivery of gene complexes via electrospun mats that contain different volumes of gelatin (Gel), collagen (Col), and polyethylene glycol (PEG) can affect gene expression by transfected cells. Non-viral complexes were formulated by using lipid modified polyethylenimine (PEI) polymer and plasmid DNAs (pDNA) like the reporter Green Fluorescent Protein (GFP) and the therapeutically relevant Bone Morphogenetic Protein-2 (BMP-2) and electrospuned after being mixed with different volumes of Gel-Col-PEG mats and delivered to human myoblast (C2C12) and mouse osteoblast cells (MC3T3). The entrapment of GFP complexes via different homogeneous electrospun fiber mats revealed that a high fraction of collagen in the mats affected the quality of the fibers and led to reduced transfection efficiency on target cells. On the other hand, the fabrication of double-layered mats that contained collagen without complexes as a first layer and gelatin-collagen-PEG with complexes as a second layer successfully induced GFP expression and ALP activity in C2C12 cells. We conclude that this study has established the advantage of formulating multilayered bioactive collagen-based mats for gene delivery applications. Full article
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9 pages, 2148 KiB  
Article
Immunogenicity of Multiple Doses of pDNA Vaccines against SARS-CoV-2
by Iman Almansour, Nabela Calamata Macadato and Thamer Alshammari
Pharmaceuticals 2021, 14(1), 39; https://0-doi-org.brum.beds.ac.uk/10.3390/ph14010039 - 06 Jan 2021
Cited by 4 | Viewed by 12544
Abstract
Since its identification in Wuhan, China, in December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has resulted in 46 million cases and more than one million deaths worldwide, as of 30 October 2020. Limited [...] Read more.
Since its identification in Wuhan, China, in December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has resulted in 46 million cases and more than one million deaths worldwide, as of 30 October 2020. Limited data exist on the magnitude and durability of antibodies generated by natural infection with SARS-CoV-2 and whether they can provide long-lasting immunity from reinfection. Vaccination has proven the most effective measure for controlling and preventing pandemics and, thus, development of a vaccine against COVID-19 is a top priority. However, the doses required to induce effective, long-lasting antibody responses against SARS-CoV-2 remain undetermined. Here, we present the development of SARS-CoV-2 vaccine candidates encoding the viral spike (S) gene, generated using plasmid (p)DNA technology, and we demonstrate the eliciting of S-specific antibodies in mice after three and four doses. The magnitude of binding and neutralizing antibody responses with three doses of synthetic, codon-optimized, full-length S (S.opt.FL) vaccine is comparable to that generated after four doses, suggesting that three doses are sufficient to elicit robust immune responses. Conversely, four doses of S1.opt pDNA vaccine, containing the S globular head, are required to elicit high levels of neutralizing antibodies. Furthermore, the S.opt.FL pDNA vaccine induces the highest serum levels of interferon (IFN)-γ, a marker for activation of cellular immune responses. Overall, our data show that three doses of S.FL pDNA vaccine elicit potent neutralizing antibody responses, with preclinical data that support the immunogenicity of these COVID-19 vaccine candidates and provide justification for further translational studies. Full article
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20 pages, 3130 KiB  
Article
Characterization of iRGD-Ligand Modified Arginine-Histidine-Rich Peptides for Nucleic Acid Therapeutics Delivery to αvβ3 Integrin-Expressing Cancer Cells
by Anna Egorova, Alexander Selutin, Marianna Maretina, Sergei Selkov, Vladislav Baranov and Anton Kiselev
Pharmaceuticals 2020, 13(10), 300; https://0-doi-org.brum.beds.ac.uk/10.3390/ph13100300 - 10 Oct 2020
Cited by 15 | Viewed by 2647
Abstract
Efficient and specific delivery of nucleic acid (NA) therapeutics to tumor cells is extremely important for cancer gene therapy. Various therapeutic strategies include delivery of DNA-therapeutics such as immunostimulatory or suicide genes and delivery of siRNA-therapeutics able to silence expression of cancer-related genes. [...] Read more.
Efficient and specific delivery of nucleic acid (NA) therapeutics to tumor cells is extremely important for cancer gene therapy. Various therapeutic strategies include delivery of DNA-therapeutics such as immunostimulatory or suicide genes and delivery of siRNA-therapeutics able to silence expression of cancer-related genes. Peptides are a promising class of non-viral vehicles which are biodegradable and can efficiently condense, protect and specifically deliver NA to the cells. Here we designed arginine-histidine-rich peptide carriers consisting of an iRGD ligand to target αvβ3 integrins and studied them as vehicles for DNA and siRNA delivery to cancer cells. Combination of iRGD-modified and unmodified arginine–histidine-rich peptides during NA complexation resulted in carriers with different ligand contents. The NA-binding and protecting properties in vitro transfection efficiency and cytotoxicity of the DNA- and siRNA-polyplexes were studied and the most efficient carrier RGD1 was determined. The ability of the peptides to mediate specific intracellular uptake was confirmed inhuman cervical carcinoma (HeLa), human kidney (293T) and human pancreatic (PANC-1) cell lines with different αvβ3 integrins surface expression. By means of RGD1 carrier, efficient delivery of the herpes simplex virus (HSV-1) thymidine kinase gene to PANC-1 cells was demonstrated. Subsequent ganciclovir treatment led to a reduction of PANC-1 cells’ viability by up to 54%. Efficient RNAi-mediated down-regulation of GFP and VEGFA gene expression was achieved in MDA-MB-231-GFP+ breast cancer and EA.hy926 endothelial cells, respectively, by means of RGD1/siRNA polyplexes. Here we demonstrated that the peptide carrier RGD1 can be considered as promising candidate for development of NA therapeutics delivery systems useful in cancer gene therapy. Full article
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Review

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31 pages, 3945 KiB  
Review
Multifunctional Delivery Systems for Peptide Nucleic Acids
by Stefano Volpi, Umberto Cancelli, Martina Neri and Roberto Corradini
Pharmaceuticals 2021, 14(1), 14; https://0-doi-org.brum.beds.ac.uk/10.3390/ph14010014 - 25 Dec 2020
Cited by 27 | Viewed by 5047
Abstract
The number of applications of peptide nucleic acids (PNAs)—oligonucleotide analogs with a polyamide backbone—is continuously increasing in both in vitro and cellular systems and, parallel to this, delivery systems able to bring PNAs to their targets have been developed. This review is intended [...] Read more.
The number of applications of peptide nucleic acids (PNAs)—oligonucleotide analogs with a polyamide backbone—is continuously increasing in both in vitro and cellular systems and, parallel to this, delivery systems able to bring PNAs to their targets have been developed. This review is intended to give to the readers an overview on the available carriers for these oligonucleotide mimics, with a particular emphasis on newly developed multi-component- and multifunctional vehicles which boosted PNA research in recent years. The following approaches will be discussed: (a) conjugation with carrier molecules and peptides; (b) liposome formulations; (c) polymer nanoparticles; (d) inorganic porous nanoparticles; (e) carbon based nanocarriers; and (f) self-assembled and supramolecular systems. New therapeutic strategies enabled by the combination of PNA and proper delivery systems are discussed. Full article
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11 pages, 852 KiB  
Review
Cell Penetrating Peptides Used in Delivery of Therapeutic Oligonucleotides Targeting Hepatitis B Virus
by Bénédicte Ndeboko, Serge Thierry Omouessi, Brice Ongali and Augustin Mouinga-Ondémé
Pharmaceuticals 2020, 13(12), 483; https://0-doi-org.brum.beds.ac.uk/10.3390/ph13120483 - 21 Dec 2020
Cited by 4 | Viewed by 2524
Abstract
Peptide Nucleic Acid (PNAs) and small noncoding RNAs including small interfering RNAs (siRNAs) represent a new class of oligonucleotides considered as an alternative therapeutic strategy in the chronic hepatitis B treatment. Indeed, chronic hepatitis B virus (HBV) infection remains a major public health [...] Read more.
Peptide Nucleic Acid (PNAs) and small noncoding RNAs including small interfering RNAs (siRNAs) represent a new class of oligonucleotides considered as an alternative therapeutic strategy in the chronic hepatitis B treatment. Indeed, chronic hepatitis B virus (HBV) infection remains a major public health problem worldwide, despite the availability of an effective prophylactic vaccine. Current therapeutic approaches approved for chronic HBV treatment are pegylated-interferon alpha (IFN)-α and nucleos(t)ide analogues (NAs). Both therapies do not completely eradicate viral infection and promote severe side effects. In this context, the development of new effective treatments is imperative. This review focuses on antiviral activity of both PNAs and siRNAs targeting hepatitis B virus. Thus, we briefly present our results on the ability of PNAs to decrease hepadnaviral replication in duck hepatitis B virus (DHBV) model. Interestingly, other oligonucleotides as siRNAs could significantly inhibit HBV antigen expression in transient replicative cell culture. Because the application of these oligonucleotides as new antiviral drugs has been hampered by their poor intracellular bioavailability, we also discuss the benefits of their coupling to different molecules such as the cell penetrating peptides (CPPs), which were used as vehicles to deliver therapeutic agents into the cells. Full article
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19 pages, 1905 KiB  
Review
Gene Regulation Using Spherical Nucleic Acids to Treat Skin Disorders
by Thomas R. Holmes and Amy S. Paller
Pharmaceuticals 2020, 13(11), 360; https://0-doi-org.brum.beds.ac.uk/10.3390/ph13110360 - 02 Nov 2020
Cited by 7 | Viewed by 3454
Abstract
Spherical nucleic acids (SNAs) are nanostructures consisting of nucleic acids in a spherical configuration, often around a nanoparticle core. SNAs are advantageous as gene-regulating agents compared to conventional gene therapy owing to their low toxicity, enhanced stability, uptake by virtually any cell, and [...] Read more.
Spherical nucleic acids (SNAs) are nanostructures consisting of nucleic acids in a spherical configuration, often around a nanoparticle core. SNAs are advantageous as gene-regulating agents compared to conventional gene therapy owing to their low toxicity, enhanced stability, uptake by virtually any cell, and ability to penetrate the epidermal barrier. In this review we: (i) describe the production, structure and properties of SNAs; (ii) detail the mechanism of SNA uptake in keratinocytes, regulated by scavenger receptors; and (iii) report how SNAs have been topically applied and intralesionally injected for skin disorders. Specialized SNAs called nanoflares can be topically applied for gene-based diagnosis (scar vs. normal tissue). Topical SNAs directed against TNFα and interleukin-17A receptor reversed psoriasis-like disease in mouse models and have been tested in Phase 1 human trials. Furthermore, SNAs targeting ganglioside GM3 synthase accelerate wound healing in diabetic mouse models. Most recently, SNAs targeting toll-like receptor 9 are being used in Phase 2 human trials via intratumoral injection to induce immune responses in Merkel cell and cutaneous squamous cell carcinoma. Overall, SNAs are a valuable tool in bench-top and clinical research, and their advantageous properties, including penetration into the epidermis after topical delivery, provide new opportunities for targeted therapies. Full article
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25 pages, 2932 KiB  
Review
Overcoming Barriers for siRNA Therapeutics: From Bench to Bedside
by Muhammad Imran Sajid, Muhammad Moazzam, Shun Kato, Kayley Yeseom Cho and Rakesh Kumar Tiwari
Pharmaceuticals 2020, 13(10), 294; https://0-doi-org.brum.beds.ac.uk/10.3390/ph13100294 - 07 Oct 2020
Cited by 97 | Viewed by 13370
Abstract
The RNA interference (RNAi) pathway possesses immense potential in silencing any gene in human cells. Small interfering RNA (siRNA) can efficiently trigger RNAi silencing of specific genes. FDA Approval of siRNA therapeutics in recent years garnered a new hope in siRNA therapeutics. However, [...] Read more.
The RNA interference (RNAi) pathway possesses immense potential in silencing any gene in human cells. Small interfering RNA (siRNA) can efficiently trigger RNAi silencing of specific genes. FDA Approval of siRNA therapeutics in recent years garnered a new hope in siRNA therapeutics. However, their therapeutic use is limited by several challenges. siRNAs, being negatively charged, are membrane-impermeable and highly unstable in the systemic circulation. In this review, we have comprehensively discussed the extracellular barriers, including enzymatic degradation of siRNAs by serum endonucleases and RNAases, rapid renal clearance, membrane impermeability, and activation of the immune system. Besides, we have thoroughly described the intracellular barriers such as endosomal trap and off-target effects of siRNAs. Moreover, we have reported most of the strategies and techniques in overcoming these barriers, followed by critical comments in translating these molecules from bench to bedside. Full article
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Other

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13 pages, 1670 KiB  
Brief Report
Targeting SARS-CoV-2 Variants with Nucleic Acid Therapeutic Nanoparticle Conjugates
by Hanah F. Huber, Majid Jaberi-Douraki, Sarah DeVader, Cesar Aparicio-Lopez, Juliet Nava-Chavez, Xuan Xu, Nuwan Indika Millagaha Gedara, Natasha N. Gaudreault and Robert K. Delong
Pharmaceuticals 2021, 14(10), 1012; https://0-doi-org.brum.beds.ac.uk/10.3390/ph14101012 - 01 Oct 2021
Cited by 3 | Viewed by 2769
Abstract
The emergence of SARS-CoV-2 variants is cause for concern, because these may become resistant to current vaccines and antiviral drugs in development. Current drugs target viral proteins, resulting in a critical need for RNA-targeted nanomedicines. To address this, a comparative analysis of SARS-CoV-2 [...] Read more.
The emergence of SARS-CoV-2 variants is cause for concern, because these may become resistant to current vaccines and antiviral drugs in development. Current drugs target viral proteins, resulting in a critical need for RNA-targeted nanomedicines. To address this, a comparative analysis of SARS-CoV-2 variants was performed. Several highly conserved sites were identified, of which the most noteworthy is a partial homopurine palindrome site with >99% conservation within the coding region. This sequence was compared among recently emerged, highly infectious SARS-CoV-2 variants. Conservation of the site was maintained among these emerging variants, further contributing to its potential as a regulatory target site for SARS-CoV-2. RNAfold was used to predict the structures of the highly conserved sites, with some resulting structures being common among coronaviridae. An RNA-level regulatory map of the conserved regions of SARS-CoV-2 was produced based on the predicted structures, with each representing potential target sites for antisense oligonucleotides, triplex-forming oligomers, and aptamers. Additionally, homopurine/homopyrimidine sequences within the viral genome were identified. These sequences also demonstrate appropriate target sites for antisense oligonucleotides and triplex-forming oligonucleotides. An experimental strategy to investigate these is summarized along with potential nanoparticle types for delivery, and the advantages and disadvantages of each are discussed. Full article
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