Poster abstracts
Poster number 168 submitted by SeyedMilad SafarSajadi
Peptide-conjugated antisense oligonucleotides for enhanced intracellular delivery and splice switching
SeyedMilad SafarSajadi (Chemistry and Biochemistry - The Ohio State University ), Yi-Meng Lo, Dennis Bong
Abstract:
Antisense oligonucleotides (ASOs) and phosphorodiamidate morpholino oligomers (PMOs) hold immense promise for correcting aberrant RNA splicing, yet their clinical efficacy remains bottlenecked by poor cellular uptake and inefficient endosomal escape. To overcome these barriers, we evaluated novel cell-penetrating peptides (CPPs) based on bifacial peptide nucleic acid (bPNA). A series of CPPs bearing systematic modifications at the ε-nitrogen of lysine residues were synthesized and conjugated to PMO and ASO sequences. Conjugates were evaluated in HeLa 654 reporter cells to measure splice-switching functional activity via restoration of EGFP fluorescence, while Cy5-labeled counterparts were tracked by fluorescence microscopy to assess cellular uptake and cytosolic entry. The delivery platforms exhibited distinct cargo-dependent performance: PMOs conjugated to modified CPPs displayed superior splice-switching efficiency compared to other PMO variants. Confocal imaging correlated these functional gains with improved intracellular dispersion rather than mere endocytic accumulation.
These findings demonstrate that delivery optimization is highly cargo-specific, establishing tailored peptide conjugations as complementary platforms for splice-switching therapeutics.
References:
Li, X. et al. The endosomal escape vehicle platform enhances delivery of oligonucleotides in preclinical models of neuromuscular disorders. Mol. Ther. Nucleic AcidsMol. Ther. Nucleic Acids 33, 273–285 (2023).
Qian, Z. et al. Discovery and mechanism of highly efficient cyclic cell-penetrating peptides. Biochemistry 55, 2601–2612 (2016).
Keywords: Antisense oligonucleotides, phosphorodiamidate morpholino oligomers, cell-penetrating peptides