Synthesis and Exon-Skipping Properties of a 3′-Ursodeoxycholic Acid-Conjugated Oligonucleotide Targeting DMD Pre-mRNA: Pre-Synthetic versus Post-Synthetic Approach

Steric blocking antisense oligonucleotides (ASO) are promising tools for splice modulation such as exon-skipping, although their therapeutic effect may be compromised by insufficient delivery. To address this issue, we investigated the synthesis of a 20-mer 2′-OMe PS oligonucleotide conjugated at 3′-end with ursodeoxycholic acid (UDCA) involved in the targeting of human DMD exon 51, by exploiting both a pre-synthetic and a solution phase approach. The two approaches have been compared. Both strategies successfully provided the desired ASO 51 3′-UDC in good yield and purity. It should be pointed out that the pre-synthetic approach insured better yields and proved to be more cost-effective. The exon skipping efficiency of the conjugated oligonucleotide was evaluated in myogenic cell lines and compared to that of unconjugated one: a better performance was determined for ASO 51 3′-UDC with an average 9.5-fold increase with respect to ASO 51.

Download Full-text

Sub-nanometric synthesis of Cu2O catalyst for Pd-free C-C coupling reactions

Reaction Chemistry & Engineering ◽

10.1039/d1re00054c ◽

2021 ◽

Author(s):

Bipul Sarkar ◽

Ankit Agrawal ◽

Reena Goyal ◽

Moses Abraham Bokinala ◽

Omvir Singh ◽

...

Keyword(s):

Cost Effective ◽

Solution Phase ◽

Synthetic Approach ◽

Coupling Reactions ◽

Chemical Route

We report a facile solution-phase-sono-chemical route for the glucose-template mediated synthesis of Cu2O nanocrystals with the well-defined sizes and shapes. The current synthetic approach offers a superficial and cost-effective route...

Download Full-text

2D-3D integration of hexagonal boron nitride and a high-κ dielectric for ultrafast graphene-based electro-absorption modulators

Nature Communications ◽

10.1038/s41467-021-20926-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Hitesh Agarwal ◽

Bernat Terrés ◽

Lorenzo Orsini ◽

Alberto Montanaro ◽

Vito Sorianello ◽

...

Keyword(s):

Boron Nitride ◽

Hafnium Oxide ◽

High Speed ◽

Hexagonal Boron Nitride ◽

Temperature Stability ◽

Cost Effective ◽

Fold Increase ◽

Building Blocks ◽

High Quality ◽

New Device

AbstractElectro-absorption (EA) waveguide-coupled modulators are essential building blocks for on-chip optical communications. Compared to state-of-the-art silicon (Si) devices, graphene-based EA modulators promise smaller footprints, larger temperature stability, cost-effective integration and high speeds. However, combining high speed and large modulation efficiencies in a single graphene-based device has remained elusive so far. In this work, we overcome this fundamental trade-off by demonstrating the 2D-3D dielectric integration in a high-quality encapsulated graphene device. We integrated hafnium oxide (HfO2) and two-dimensional hexagonal boron nitride (hBN) within the insulating section of a double-layer (DL) graphene EA modulator. This combination of materials allows for a high-quality modulator device with high performances: a ~39 GHz bandwidth (BW) with a three-fold increase in modulation efficiency compared to previously reported high-speed modulators. This 2D-3D dielectric integration paves the way to a plethora of electronic and opto-electronic devices with enhanced performance and stability, while expanding the freedom for new device designs.

Download Full-text

Personalized Development of Antisense Oligonucleotides for Exon Skipping Restores Type XVII Collagen Expression in Junctional Epidermolysis Bullosa

International Journal of Molecular Sciences ◽

10.3390/ijms22073326 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3326

Author(s):

Michael Ablinger ◽

Thomas Lettner ◽

Nicole Friedl ◽

Hannah Potocki ◽

Theresa Palmetzhofer ◽

...

Keyword(s):

Epidermolysis Bullosa ◽

Antisense Oligonucleotides ◽

Exon Skipping ◽

Junctional Epidermolysis Bullosa ◽

Reading Frame ◽

Collagen Expression ◽

Promising Tool ◽

Mucous Membranes ◽

Personalized Approach ◽

Xvii Collagen

Intermediate junctional epidermolysis bullosa caused by mutations in the COL17A1 gene is characterized by the frequent development of blisters and erosions on the skin and mucous membranes. The rarity of the disease and the heterogeneity of the underlying mutations renders therapy developments challenging. However, the high number of short in-frame exons facilitates the use of antisense oligonucleotides (AON) to restore collagen 17 (C17) expression by inducing exon skipping. In a personalized approach, we designed and tested three AONs in combination with a cationic liposomal carrier for their ability to induce skipping of COL17A1 exon 7 in 2D culture and in 3D skin equivalents. We show that AON-induced exon skipping excludes the targeted exon from pre-mRNA processing, which restores the reading frame, leading to the expression of a slightly truncated protein. Furthermore, the expression and correct deposition of C17 at the dermal–epidermal junction indicates its functionality. Thus, we assume AON-mediated exon skipping to be a promising tool for the treatment of junctional epidermolysis bullosa, particularly applicable in a personalized manner for rare genotypes.

Download Full-text

In vivocomparison of 2′-O-methyl phosphorothioate and morpholino antisense oligonucleotides for Duchenne muscular dystrophy exon skipping

The Journal of Gene Medicine ◽

10.1002/jgm.1288 ◽

2009 ◽

Vol 11 (3) ◽

pp. 257-266 ◽

Cited By ~ 128

Author(s):

Hans A. Heemskerk ◽

Christa L. de Winter ◽

Sjef J. de Kimpe ◽

Petra van Kuik-Romeijn ◽

Niki Heuvelmans ◽

...

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Antisense Oligonucleotides ◽

Exon Skipping

Download Full-text

A Facile Synthesis and Characterization of Highly Crystalline Submicro-Sized BiFeO3

Materials ◽

10.3390/ma13133035 ◽

2020 ◽

Vol 13 (13) ◽

pp. 3035

Author(s):

Dovydas Karoblis ◽

Diana Griesiute ◽

Kestutis Mazeika ◽

Dalis Baltrunas ◽

Dmitry V. Karpinsky ◽

...

Keyword(s):

Bismuth Ferrite ◽

Cost Effective ◽

Xrd Analysis ◽

Synthetic Approach ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Dsc Measurements ◽

Optimal Annealing Temperature ◽

Synthesized Materials

In this study, a highly crystalline bismuth ferrite (BFO) powder was synthesized using a novel, very simple, and cost-effective synthetic approach. It was demonstrated that the optimal annealing temperature for the preparation of highly-pure BFO is 650 °C. At lower or higher temperatures, the formation of neighboring crystal phases was observed. The thermal behavior of BFO precursor gel was investigated by thermogravimetric and differential scanning calorimetry (TG-DSC) measurements. X-ray diffraction (XRD) analysis and Mössbauer spectroscopy were employed for the investigation of structural properties. Scanning electron microscopy (SEM) was used to evaluate morphological features of the synthesized materials. The obtained powders were also characterized by magnetization measurements, which showed antiferromagnetic behavior of BFO powders.

Download Full-text

Digital Droplet PCR for the Absolute Quantification of Exon Skipping Induced by Antisense Oligonucleotides in (Pre-)Clinical Development for Duchenne Muscular Dystrophy

PLoS ONE ◽

10.1371/journal.pone.0162467 ◽

2016 ◽

Vol 11 (9) ◽

pp. e0162467 ◽

Cited By ~ 14

Author(s):

Ruurd C. Verheul ◽

Judith C. T. van Deutekom ◽

Nicole A. Datson

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Antisense Oligonucleotides ◽

Exon Skipping ◽

Absolute Quantification ◽

Clinical Development ◽

Digital Droplet Pcr ◽

Droplet Pcr ◽

The Absolute

Download Full-text

Nucleobase-modified antisense oligonucleotides containing 5-(phenyltriazol)-2′-deoxyuridine nucleotides induce exon-skipping in vitro

RSC Advances ◽

10.1039/c7ra10964d ◽

2017 ◽

Vol 7 (86) ◽

pp. 54542-54545 ◽

Cited By ~ 6

Author(s):

Bao T. Le ◽

Mick Hornum ◽

Pawan K. Sharma ◽

Poul Nielsen ◽

Rakesh N. Veedu

Keyword(s):

Antisense Oligonucleotides ◽

Exon Skipping

We investigated the potential of nucleobase-modified antisense oligonucleotides to induce exon-skipping, and found that 5-(phenyltriazol)-2′-deoxyuridine-modified antisense oligonucleotides induced efficient exon-skipping in vitro.

Download Full-text

Nanoparticle Delivery of Antisense Oligonucleotides and Their Application in the Exon Skipping Strategy for Duchenne Muscular Dystrophy

Nucleic Acid Therapeutics ◽

10.1089/nat.2013.0450 ◽

2014 ◽

Vol 24 (1) ◽

pp. 87-100 ◽

Cited By ~ 22

Author(s):

Maria Sofia Falzarano ◽

Chiara Passarelli ◽

Alessandra Ferlini

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Antisense Oligonucleotides ◽

Exon Skipping ◽

Nanoparticle Delivery

Download Full-text

Induction of Dystrophin Expression by Exon Skipping in mdx Mice Following Intramuscular Injection of Antisense Oligonucleotides Complexed with PEG–PEI Copolymers

Molecular Therapy ◽

10.1016/j.ymthe.2005.11.025 ◽

2006 ◽

Vol 14 (1) ◽

pp. 88-96 ◽

Cited By ~ 24

Author(s):

Jason H. Williams ◽

Shashank R. Sirsi ◽

Daniel R. Latta ◽

Gordon J. Lutz

Keyword(s):

Antisense Oligonucleotides ◽

Intramuscular Injection ◽

Exon Skipping ◽

Mdx Mice ◽

Dystrophin Expression

Download Full-text

Eteplirsen treatment for Duchenne muscular dystrophy

Neurology ◽

10.1212/wnl.0000000000005680 ◽

2018 ◽

Vol 90 (24) ◽

pp. e2146-e2154 ◽

Cited By ~ 67

Author(s):

Jay S. Charleston ◽

Frederick J. Schnell ◽

Johannes Dworzak ◽

Cas Donoghue ◽

Sarah Lewis ◽

...

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Western Blot ◽

Reverse Transcription ◽

Exon Skipping ◽

Fold Increase ◽

Cell Penetration ◽

Reverse Transcription Pcr ◽

Dystrophin Expression ◽

Immunofluorescence Intensity

ObjectiveTo describe the quantification of novel dystrophin production in patients with Duchenne muscular dystrophy (DMD) after long-term treatment with eteplirsen.MethodsClinical study 202 was an observational, open-label extension of the randomized, controlled study 201 assessing the safety and efficacy of eteplirsen in patients with DMD with a confirmed mutation in the DMD gene amenable to correction by skipping of exon 51. Patients received once-weekly IV doses of eteplirsen 30 or 50 mg/kg. Upper extremity muscle biopsy samples were collected at combined study week 180, blinded, and assessed for dystrophin-related content by Western blot, Bioquant software measurement of dystrophin-associated immunofluorescence intensity, and percent dystrophin-positive fibers (PDPF). Results were contrasted with matched untreated biopsies from patients with DMD. Reverse transcription PCR followed by Sanger sequencing of newly formed slice junctions was used to confirm the mechanism of action of eteplirsen.ResultsReverse transcription PCR analysis and sequencing of the newly formed splice junction confirmed that 100% of treated patients displayed the expected skipped exon 51 sequence. In treated patients vs untreated controls, Western blot analysis of dystrophin content demonstrated an 11.6-fold increase (p = 0.007), and PDPF analysis demonstrated a 7.4-fold increase (p < 0.001). The PDPF findings were confirmed in a re-examination of the sample (15.5-fold increase, p < 0.001). Dystrophin immunofluorescence intensity was 2.4-fold greater in treated patients than in untreated controls (p < 0.001).ConclusionTaken together, the 4 assays, each based on unique evaluation mechanisms, provided evidence of eteplirsen muscle cell penetration, exon skipping, and induction of novel dystrophin expression.Classification of evidenceThis study provides Class II evidence of the muscle cell penetration, exon skipping, and induction of novel dystrophin expression by eteplirsen, as confirmed by 4 assays.

Download Full-text