Closed-Ended Linear Duplex DNA with Interrupted Self-Complementary Arms
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current gene delivery vectors, including viral and bacterial-derived vectors, induce immune responses, have limited transgene carrying capacity, are labor-intensive and expensive, and face challenges with insertional mutagenesis and immune recognition.
Innovation Solution
The development of closed-ended linear duplex DNA (ceDNA) with asymmetric interrupted self-complementary sequences that form covalent linkages, reducing immune response and insertional mutagenesis, and enhancing expression and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If viral vectors are used for gene delivery, then gene transfer efficiency is improved, but immune response and insertional mutagenesis increase
Solution Approach 1:
The patent extracts and eliminates the viral capsid and other viral components from the gene delivery system, retaining only the essential genetic information in a plasmid-based vector. This extraction removes the source of immune recognition and insertional mutagenesis while preserving gene transfer capability through non-viral mechanisms.
Solution Approach 2:
The patent employs transient expression systems where the plasmid DNA is delivered but does not integrate into the host genome. The vector is designed to be temporary and non-persistent, eliminating long-term immune consequences and mutagenic risks associated with viral vectors that require integration for sustained expression.
2Object-affected harmful factors
If plasmid DNA vectors are used for gene delivery, then immune response is reduced, but transgene carrying capacity is limited
Solution Approach 1:
The patent segments the plasmid DNA into smaller, manageable units that can be efficiently delivered and expressed without overwhelming the host cell's processing capacity. This segmentation allows multiple transgenes to be delivered through repeated administrations while maintaining low immune response, as each plasmid unit remains relatively small and non-integrating.
3Productivity
If symmetric interrupted self-complementary sequences are used, then replication is enabled, but insertional mutagenesis and immune response increase
Solution Approach 1:
The patent introduces asymmetric interruptions in the self-complementary sequences, creating terminal structures that are not perfectly symmetric. This asymmetry prevents efficient recombination and integration into host genomes, thereby eliminating insertional mutagenesis while still allowing controlled replication through the asymmetric terminal resolution mechanism.
Solution Approach 2:
Instead of using conventional symmetric terminal repeats that promote integration, the patent inverts the approach by using asymmetric terminals that specifically prevent integration. The terminal resolution site is positioned to allow controlled replication initiation while the asymmetric structure blocks subsequent recombination events that would cause mutagenesis.
4Reliability
If viral vectors are used for gene delivery, then gene expression is enhanced, but production complexity and cost increase
Solution Approach 1:
The patent employs self-service replication mechanisms where the plasmid DNA utilizes the host cell's own replication machinery to amplify and express the transgene. This eliminates the need for complex viral assembly systems, purification protocols, and quality control procedures required for viral vector production, significantly simplifying manufacturing while maintaining reliable gene expression.
Data Source
AI summary
Aspects of the disclosure relate to a nucleic acid comprising a heterologous nucleic acid insert flanked by interrupted self-complementary sequences, wherein one self-complementary sequence is interrupted by a cross-arm sequence forming two opposing, lengthwise-symmetric stem-loops, and wherein the other of the self-complementary sequences is interrupted by a truncated cross-arm sequence. Methods of delivering the nucleic acid to a cell are also provided.